I lived in Lubbock, Texas for nearly 10 years back in the early 2000's. My neighbor was a retired Texas Tech physics professor who had built a thermal battery in his garage. At first when I heard of a thermal battery I laughed. What for and why?! George, my neighbor, was more than happy to explain. He proceeded to explain that his ~600' of 3/8" black UV resistant tubing in a long box frame (~12' by 6') produced boiling hot water in a few hours each day. He had a 300 gallon stainless steel insulated container on a legs with a few different pumps and lines going out. One went to his jacuzzi, another to his hot water heater (or preheater), and another to a garage heater. During the summer, he hardly ever turned it on, but from late October until March we'd see billows of steam rising from his back yard when he took off the jacuzzi lid. It could be 40 degrees outside and you could hear the stainless steel container bubbling with what I assumed was boiling water. I know you could feel the heat when you stood next to it. George taught me a lot about physics over the years. He passed in March. Thank you ol' buddy for all the knowledge.

@louf7178

2 жыл бұрын

Awesome

@nanouekonzo5581

2 жыл бұрын

Rest in peace Georges, what a wonderful neighbour he was.

@emilsmadvlogs5879

2 жыл бұрын

RIP George He sounded like a good guy, with a big heart and brain

@AtTheBarn

2 жыл бұрын

From Lubbock long ago! nice seeing comments from folks out there still!

@vikassm

2 жыл бұрын

George sounds like an awesome person! I live in Bangalore, India, which apparently has the highest number of solar (thermal) hot water rooftop installations in the world! I'm pretty sure we've had one (or two) in every home I've lived in, atleast for the last 2 decades. One of those things that you use every day, but never notice. I can't remember a day when we didn't have hot water!! There were days without water, at all, but we always had hot water 😂😂

It's possible to enclose the back of the PV panel and run water through the back of it as a cooling jacket. This means you heat water, generate electricity and keep the panel cool which boosts its efficiency. Would be great to see you attempt something like that.

@BurninGems

2 жыл бұрын

Yes, this please!

@jacobfullerton1310

2 жыл бұрын

This is true, PV's would greatly benefit from cooling and can double-dip on the efficiency

@rockspoon6528

2 жыл бұрын

Correct. Semiconductor devices are more efficient at cooler temperatures- from lasers to transistors.

@SoloRenegade

2 жыл бұрын

cool the PV, while preheating the water for the solar water system...

@franknielsen6620

2 жыл бұрын

Also think this would be an interesting experiment though i think it would have already been a product if cost, efficiency and reliability were reasonable.

This panel can put out close to 100 watts kzread.infoUgkxOqI2yqX0XVrhR2BMJciTWrHJpG8FhJyg when positioned in the appropriate southernly direction, tilted to the optimal angle for your latitude/date, and connected to a higher capacity device than a 500. The built in kickstand angle is a fixed at 50 degrees. Up to 20% more power can be output by selecting the actual date and latitude optimal angle.The 500 will only input 3.5A maximum at 18 volts for 63 watts. Some of the excess power from the panel can be fed into a USB battery bank, charged directly from the panel while also charging a 500. This will allow you to harvest as much as 63 + 15 = 78 watts.If this panel is used to charge a larger device, such as the power station, then its full output potential can be realized.

I try playing these videos in the background while I'm doing other things, but your explanations are so thorough and technical that it becomes nearly impossible to follow without giving it my full attention. The cognitive nutritional density of your videos is second to none on this platform.

@eddietee6305

Жыл бұрын

"Cognitive nutritional density". Wow.

@Vito_Tuxedo

Жыл бұрын

@@eddietee6305 Yeah...I like that; a more interesting way of saying "information density", which is among the highest on KZread. 😎

@eddietee6305

Жыл бұрын

@@Vito_Tuxedo verbosity!

@deepaksudhakar1

Жыл бұрын

Exactly...

@jeksdad5979

Жыл бұрын

Solar is the way to go!

in Syria, every house or apartment has thermal solar panels. They are amazing and work very reliable. And no, we don't use pumps, if the house is not very high. Close to the panels we have an isolated tank, which get filled by the water pressure of the grid. Then the water gets heated and the gravity does the job delivering it to your house. And yes, even in the winter when the sun comes out, we get good warm water. It is the best investment a house owner should do.

@thirtythree160

2 жыл бұрын

Who makes the solar thermal panels that are used? Manufacturer.

@MusikCassette

2 жыл бұрын

I would guess that in Syria that works for a longer part of the year than further north

@dantyler6907

2 жыл бұрын

@@thirtythree160 YOU manufacture the thermal panel(s). Not hard, a couple trips to a home Depot.

@thomasneal9291

2 жыл бұрын

"They are amazing and work very reliable" are they bomb resistant too? Is it nice to be able to isolate yourself so well from the civil war there?

@Mobius_striptease

2 жыл бұрын

@@thomasneal9291 Take that elsewhere, this isn't the place.

When I was in high school, we had two vakuum tube water heating panels on our roof in Germany. This was a great investment as is, but it became especially clear in a year when both my parents were unemployed and we could not afford fuel for the heating system. These two panels allowed a familiy of five to take luke warm showers throughout the Winter.

@zeldazackman

2 жыл бұрын

Lukewarm is still better than freezing, especially in the dead of winter.

@eyeballengineering7007

2 жыл бұрын

This is why I like the idea of using PV panels with a heating element. You get full temperature.

@MysticalDork

2 жыл бұрын

@@eyeballengineering7007 only if you've got enough of them though! You'd need several times the area of the thermal system - double the area at least, just to reach lukewarm. A more efficient method would be to use a combination of the two, with the PV array powering a heat pump, to concentrate the sparse energy from the thermal system down into a smaller volume of hotter water.

@Meddlmoe

2 жыл бұрын

@@eyeballengineering7007 Note that this was 20 years ago. The system was quite complex with heat storage tank, and excess heat radiator, multiple electronic valves, etc. Also the people who installed it did not make sure that the metals of the different lines are compatible with eachother, which lead to an expensive renovation, but that is just bad craftsmanship. Today it would probably be easier to use PV panels and a heat pump. You probably still need the heat storage, because battery storage for heating is still expensive.

@flexairz

2 жыл бұрын

@@eyeballengineering7007 In the dead of winter with low sun, there isn't much power from pv panels.

I discovered your channel a few weeks ago and I will be honest. You rekindled my love for science. I have not seen anyone explain things the way you do. Thank you for doing what you do.

@TechIngredients

2 жыл бұрын

Thanks! Glad to have you on board.

@TheBlairHouseProject

Жыл бұрын

@@TechIngredients Agreed. You have an excellent and thorough approach. Questions on this project: I know radiant floor systems recomends PEX AL PEX to stop oxygen ingress and therefore corrosion building up in the system. Can you comment on that and lifespan of this system?

@TheBlairHouseProject

Жыл бұрын

@@TechIngredients One other question: Could you explain why setting the coil into a block of black pigmented concrete would be inferior? It seems that it would be a lot more resilient than glass and provide better protection for the PEX; especially from long term UV damage.

I had just found your channel and wanted to say that I appreciate the way you explain the reasoning behind a choice and the technical side of what is being discussed. No hand waving or not going into detail. I very much so appreciate that.

I really wish I had a teacher like you at any point of my education. You're so articulate down to point of complete understanding. It's beautiful... thank you for the videos.

@scoutsapp5624

2 жыл бұрын

I want to like your comment but I don’t want to ruin the number.

@specialk411

2 жыл бұрын

… the Beaty is, that your education is still incomplete and through the power of the Internet he is your teacher! You just learned by watching the video!

I've seen the use of electric water heaters as overload devices for DIY water turbines in off grid situations. Which is a cool way to store or use what would otherwise be wasted.

@bobsaturday4273

2 жыл бұрын

makes sense

@pawetsufi

2 жыл бұрын

Also in wind turbine it's common to have dump resistor that slows down the turbine if there is no other load (batteries are fully charged or something). And the dumo resistor can be water heater.

@joshuaj.aguero2225

2 жыл бұрын

Seems like if you finish heating the water then put excess energy into pumping water up to a higher elevation. Then it can be a circular system, you won’t have to pump as much water to keep pressure in times of peak/excess energy so it would be a great time to take a hot shower! Just like with rainwater harvesting but with electricity.

@gabedarrett1301

2 жыл бұрын

That's actually quite ingenious!

@trplankowner3323

2 жыл бұрын

Energy storage to a heat sump is an excellent way to store energy you don't have an immediate use for. Still your first choice should be an intelligent / programable electrical load management system. It requires rethinking the way most of us use energy in our homes. A well thought out system can minimize the maximum production capacity of your system and save you a lot of up front money. Which is what I've always thought was the most attractive reasons for an electric vehicle. Make your own transportation energy and get off the gasoline price roller coaster.

I built a similar solar water heater for my outdoor shower using about 12 feet of 4 inch black PVC pipe. It provides hot water in the Pacific Northwest from March to October, and worked very, very well, to the point I had to caution people about the need to mix cold BEFORE getting in the shower. Adding a glass cover made it too efficient, and the high temperatures melted the PVC joints enough that they popped off from the pressure. Thanks for the video!

@Humbulla93

Жыл бұрын

Now that's a sentence you won't hear often ,,too efficient" . Awesome Copper tubes with those crimp joints should Work. If you use a sooty flame (Carbon Nanotubes) to make the Copper tubes black it should be even more efficient due to copper and Carbon Nanotubes transmitting heat 1000x that of PVC

This somewhat illustrates the difference between the theoretical and the practical. Starting in the late 80s and early 90s, various neighbors of mine began installing solar hot-water systems of this type while others began installing PV systems. Not one of the hot-water systems in my neighborhood is still in use because they always had maintenance issues and required monitoring and attention. The last one that I saw taken out was because a buyer of that house required its removal as a condition of sale. I have not seen that happen with PV. Most of the PV systems are still sitting here (often with a set of replacement panels) because they are very simple and reliable with little maintenance or further investment of time or money required until decades later when the panels are no longer producing sufficiently useful power.

@nathanwise6385

Жыл бұрын

Agreed. All the ones in my neighborhood fell out of use,due to maintenance as well.

@josepeixoto3384

Жыл бұрын

THANK YOU, that is what i see all over here around me too; i am in Porto, Portugal ( that poor place where the INjustice system sucks big time, ask me how i know ); from my roof i have a clear view with binoculars of some 60 roofs at the same angle, and 15 years ago there were 10 or 15 hot water panels on them, and about 10 electrical PV panels; today i see only 3 hot water ones but 23 PV ones; my PV panels are about 10 years old,they have been performing great, no breakdowns at all,apart from the occasional inverter failure; luckily i can build them,and so,i have them modified to use main ICs in boards in sockets and it's just a matter of pulling one out and pushing a new one in,once every 2 or 3 years, they only cost 3 or 4 euros each,delivered from china;they are the famous SG3525+LM358 board for the first stage to get 380VDC, and the EGS002 board for the second stage to get 220VAC 50hz; coupled with the Lifepo4 batteries they run the whole house,not just the hot water; Solar panels never breakdown, i never heard one one failing,it's just amazing,they last 20 or 25 years without fail; inverters are another story,but i use the cheap 150 euro chinese ones,they say 5000 watts,but they are good for 2500w all day; their 16 mosfets and their 4 IGBTs never braek down,it's the smaller boards,the control board ICs, that fail,and theey were sanded down by the maker,so i can´t replace them; i now have 1 more new second stage unit ,an open unit,no box,no volt meters, of 3000 W or more continuous, a small monster with 8 IGBTS, that only cost me 52 euros delivered,and it uses the EGS002 board of which i have a few in stock, but this thing is so over sized that it probably will last a long time; i get 2000 watts max (that is 200WH of elec juice every hour!!) from the Sun,from my 8 older panels,plenty in the summer,not enough in cloudy or winter days, when they only deliver 100 or 200,sometimes 50W and less; of course, near ZERO at night; I'd rather deal with wires than with pipes thru the house, and most of the wiring was already there; and again, with a proper MPPT,LifePo4s,and inverters, PVs run the whole house from the whole March until the end of October; and some days in winter too at least partially; I have a 24 volt system,i started small,less batteries, pity, should have been a 48 V volt; 24 V are good only up to 3000 watts max,and they require heavier wires that 48 volts too.

@notajalapeno4442

Жыл бұрын

here in Israel everybody has a solar water heater (including apartments) and it works great

@ReflectedMiles

Жыл бұрын

@@notajalapeno4442 Yes and no. The usual dud shemesh is still maintenance-intensive compared to PV, and it does not get nearly as cold there as in much of the US and northwestern Europe, which adds to the design complexity for deep-freeze protection and therefore more maintenance. Even in Israel, they have to have a variable supplementation system in winter in almost every application, which is more complex than just plugging PV into an existing electrical panel.

"while I was jawboning. . . . ." I love everything about this channel.

@benholroyd5221

2 жыл бұрын

Except I know what boning is. So jaw boning would be like that? .... Or is that why you love the channel...

This channel keeps my faith in humanity

It would be nice to see how a coil of copper pipe would perform in comparison with a pex pipe. Great video!

@SUPERMAKFISH

Жыл бұрын

The Copper would conduct the energy at a greater speed than the Pex. However, since a therm of energy is permanent, it is going to move from high energy to low energy fairly efficiently. It won't simply disappear. The cost today of 200" of 1/2 inch copper tubing is around 750.00. The cost of the same length of Pex is around 105.00. Huge cost difference. And unless you require an instant heat, the added cost would be unnecessary because, the heat will find it's way into the pex. My garden hose laying on the ground gets hot enough to burn me when I first turn the water on. And, that's with no thermal glass, no box.

@chrisdaniel1339

Жыл бұрын

@@SUPERMAKFISH I just purchased 2 - 100 ft coils of 1/2" OD soft copper coils for $182 Copper tubing sales Browns Summit, NC.

@panospapadimitriou3498

Жыл бұрын

@@SUPERMAKFISH for sure a house can be super hot and less costy if you store some thermal activity in good sealed tanks!!!! my next project!!!!! but not before instal some off grid electricity backup storage

This is great. I get so many idea from your videos yet don't have the time to touch a fraction of it; I feel like I'm always playing catch-up just in terms of skills and time to get stuff done. Keep up the good work.

As an EE, I really enjoy your work and that of Ben at Applied Science for my continuing education. No One of us knows it all but we can all press on and continue to learn. THANK YOU for your contributions in science and your empirical research which you share with all of us !!

@TechIngredients

2 жыл бұрын

Thank you.

@mySeaPrince_

2 жыл бұрын

@@TechIngredients I have an idea .. Will need a bit of thinking .. You can use a pinned comment.. As there are 2.4k comments.. it's a lot to wade through.. It could be used for comments to improve or modify what your video is about... I don't remember seeing... Have you done a video about using those ceramic resistors? and how to calculate the Actual resistance? What I would really like to know is a way of doing a cost effective and affordable electronic PV dump load circuit.. maybe in incremental stages and making the water heater element, from resistors and resistance wire.. apparently some say use mains voltage ones but I'm not sure.. ... Back to feedback idea.. and do follow up video thanking and explaining them .. a winter task..? I'm been living off grid over 33 years .. Low budget, no subsidies etc.. I've still got the decades old little glass panels.. I'm in the process of setting up a KZread channel.. this has made me think I should film and talk about the early days of those panels... they were expensive but were worth it to not hear the engine or generator running.. I live on a Boat .. monetary or environment were in mind.. my sanity and to hear the birds not coughing was uppermost.. Thank you for your channel and in part making me realise I should do a channel.. Maybe you can inspire others to do a channel of what they have done.. the more this is normalised the quicker the reduction in planetary damage... I liked you saying about subsidies etc.. UK gov keeps giving £b to rich people here.. that makes them £s and they don't pay it back..... You made me laugh about cursing the universe... Sorry bit long comment.. hope of use... Kindest regards Mark and Bella...

@patrickallfrey6148

2 жыл бұрын

What is News most people in the know already aware of that But they also know that to much hot water can be a major embarrassment where as surplus electrons can be shed to the grid or otherwise dumped

@gauravsarraf

2 жыл бұрын

@Tech ingredients is it possible to use this hot water to generate electricity with a stirling engine?? I wonder what efficiency gains it might have over PV. Also, Stirling with solar heating is definitely cheaper than PV.

@DaveMody

2 жыл бұрын

@@gauravsarraf So you are touching on the holy grail of energy harvesting. Thermal Energy (say Joule or BTU) is more useful when it's at a higher temperature. Recovering energy from low temperature heat sources (like 20 or 30 deg C) is generally not economical. If it was, oh boy! Sterling engines, Organic Rankine cycle, thermoelectric devices all work at fairly high temperatures (relative to 30 deg C). I'd love to see the creative ideas that come out of a build to optimized energy recovery from a 30 deg C heat source.

9:04 upcoming aircrete video? Now that's a perfect fit for the channel, can't wait.

Thank you for producing such interesting content. Your attention to detail is appreciated.

I read an article of a home heated by water run over black aluminum roof panels. This provided hot water for the home and also heat for forced air heating. The hot water was collected in a 1600 gallon container in the basement. The water tank was surrounded by large rocks, then a layer of insulation. Air was blown through the air spaces between the rocks to heat the home. The fuel usage in Virginia dropped from about 690 barrels of heating oil to about 90. I think this was a journal article in Solar published in the 1970's.

Was actually expecting a higher difference in temperature due to the inefficiency of PV. What id love to see is what happens if you leaverage the benifit of generating electric energy rather than heat energy, by for example using a heat pump rather than just "burning" the electricity. This would also allow for other sources of electrical energy like wind and water power to be used more efficiently. Also i think it is worth taking into consideration what happens once your water is heated. Especially thinking about seasonal storage here. Id love to see a future where we use the energy generated during summer to produce synthetic fuels that we can store and use to heat our homes in Winter

@EonZuurmond

2 жыл бұрын

I strongly second this. Most air conditioners have COP of 2.3 to 3.5 (Wikipedia), meaning that you can expect up to 3.5 times the heating that you would from resistive heating as was done in this experiment. If I had to future-proof, I'd also take into account the flexibility of electricity and the forcing function globally for improved heat pumps and more efficient PV. Solar water heating, as efficient as it is, could not be expected to improve much. I'd rather invest in infrastructure for the former, even at a greater initial capex.

@flymypg

2 жыл бұрын

Came here to say this. Heat pumps are the best way to use electricity for heating, including hot water heaters.

@mckenziekeith7434

2 жыл бұрын

Good comment. Interesting. There are probably a lot of places that have AC or refrigeration and also need hot water.

@mangeload

2 жыл бұрын

@@mckenziekeith7434 any ideas on inlet pipe freeze prevention for off grid use?

I have been working on adding cooling to the back of solar panels to cool them, hopefully to raise their efficiency on hot days as well as prolonging their life. The cooling will also provide pre-heating for my hot water heater and/or my pool. I’m also going to try to cool my house in the summer by cooling the house by running pool water through a forced air radiator in my house.

@xmtxx

2 жыл бұрын

That's the way to go. It baffles me nobody is doing it. It's (almost) free energy after all.

@rickrack78

2 жыл бұрын

@@xmtxx, I came upon the idea and developed some approaches. then, I thought to look and see if anyone else had the same idea. I found a few people who had done it or at least researched it and proposed methods. Now, with bifacial panels that already have two sealed surfaces, it would be as easy as designing and bonding a cooling circuit to the back… I’m working on one that bonds “U” shaped circuitous channels to the bottom glass. This would couple the water/coolant directly to the glass, as the cap on the “U” channels, making them tubes

@Bantorthe2nd

2 жыл бұрын

Hey! Were currently building our house and would be really interested if you have any designs or links you are willing to share? 😊 Totally understand if not though. Thanks.

@xanfsnark

2 жыл бұрын

They do exist commercially, often under the term "hybrid solar panels", although they don't have a huge market segment. I think one of the big barriers to adoption is that you need an installer who can handle both the electric and plumbing work, and it needs to be integrated both into the electric with an inverer, and the hot water system, which increases the cost at time of installation. I also don't think there's as many people/companies doing it, which also makes it harder to get right now.

@Chrislk1986

2 жыл бұрын

Cool idea. Are there submersible PV panels? Would be cool to see how water depth over a PV panel affects efficiency. Would be cooler to see if that efficiency loss can be made up from extracting heat from the PV panels.

Dear sir, the information you provide is soo useful across many fields! I appreciate the results you are after! Thank you for your work it is much appreciated!

Love that you even included the pump's specs !

Solar water heaters are great for purposes like heating a pool or a camp shower, but what would it take to actually pipe the warmed water into a standard home water system? I suppose you would just pipe it in line after the hot water split off before entering your water heater? A relitive of mine has a commercially made solar pool heater that uses what looks like a heavy duty version of black coroplast. A pump feeds water up onto the roof, and it then gravity feeds through the corrugations in the plastic sheet and down into the pool. I thought that was a pretty clever idea to get a huge surface area with a fraction of the material as a spool of pipe.

@deth3021

2 жыл бұрын

Don't you normally use them with heat pumps or something? Rather than directly piping it in.

@Oehr64EatShitGoogle

2 жыл бұрын

I have a commercial solar water heater at home with about 1.5x the size of the one in the video: it uses a separate water circuit to collect the heat and then transfer it to or rather share with the hot water circuit/boiler of the home. becomes ultra hot in summer! In winter, it is pretty much useless, as he said in the video

@p529.

2 жыл бұрын

We use a heat collector thing and we have a tank in the cellar and I think there is a spiral in there that heats the water in the tank, it's not water that is getting heated in our system but glycol I think. In summer we usually reach like 100°C on the roof and end up with like 80-90°C in the tanks and that is plenty for showering and stuff like that

@rw-xf4cb

2 жыл бұрын

Yeah pool heaters are great, until they spring a leak and the pool is salt water :(

@flyinhigh689

2 жыл бұрын

its generally not hard at all, you usually have a heat sink / exchanger before your hot water heater. they are just a water tank with a coil in them to pre heat the water before it gets to the water heater.

When I lived in Turkey these solar water heaters were very common, and in Alanya where I lived I only had about a week per year when the water was lukewarm the rest of the year the water was burning hot, a really great money saver.

There are a few things I would love to see you test out. 1. Vacuum tube glass that is tinted dark or a beer/soda can heater. Both of these options are similar to your coiled pex tubing but I've seen them get extremely hot and move air using a 12v pc fan with a solar panel. I've even seen the glass vacuum tubing marketed as a solar cooker. Another thing I've seen is what's called a passive wall. Maybe not build it on your main home, but if you have a non powered shed that you work in, pick the side that gets the most sun during the winter and build a transparent box thats as air tight u can make it using greenhouse plastic tiles that look like metal roof tiles, on the outside and dark paint underneath. Inside this box cut vents along the top and bottom of the structure, protect it from critters with metal mesh and put one way air valves (like a piece of tar paper, cork or even adjustable dampers that flap one way only.) that lead inside the building, and on the bottom have it lead out to the greenhouse. The enclosed wall box would create a greenhouse effect and also generate pressure with the hot air that would blow into the building via expansion. As the air cools it gets sucked back out into the greenhouse wall and expansion occurs on a cycle. I've seen one person do this before on YT but you have a better channel to measure and collect data. Passive systems are the best systems!

@alanwardrop9575

Жыл бұрын

That is a version of Trombe wall. If the back of the box has high thermal mass (such as a brick wall) it can help keep the building warm into the night.

For a long time I wondered how the two methods compared. You did a great job of quantifying the differnece.

It would be really interesting if you ran the test with data logging, so we could see the water panel's efficiency drop as it heats up and at what point it becomes significant.

@JonathanW5444

2 жыл бұрын

I think this would be the case with both... As the panels reach their max output the power curve will have a similar shape. But even more interesting would be if you had the data and could take the area of both curves to find the total power output of both and how they compare.

@pietersmit621

2 жыл бұрын

@@JonathanW5444 the pv output is not affected by water temperature.

@trplankowner3323

2 жыл бұрын

@@pietersmit621 But it is effected by the temperature of the panel itself. I don't think it would be to the degree that the water heater's efficiency drops as it reaches it's peak though. Two different physics involved there. Still, there's a lot of data to consider there, with more instrumentation of course.

@justingort1

2 жыл бұрын

@@trplankowner3323 not just the temperature of the panels also the temperature of the resistors. these will increase in resistance as they heat up. this will lower the current draw and therefor make the panels less efficient as they are not in there optimal current output anymore. its one of the reasons why MPPT chargers are better than PWM ones. the MPPT changes its charge rate based on the optimal current draw from the panels

@trplankowner3323

2 жыл бұрын

@@justingort1 While all of that is absolutely true and pertinent in certain perspectives. That isn't what I was referring to, I was agreeing that more data could be useful on this comparison. There's so many different aspects involved in this test that many could spend weeks or even months delving into the details. On each system. Still I think that the gross point of the comparison remains and is valid, much more energy is gathered by the hot water collector. However, if you need electricity and not heat, short of building a greatly more intricate system, stick with the PV panels!

It would be really interesting to compare the resistive heating used in this video with a more efficient mechanism like a heat pump to see if that arrangement would outperform so direct solar heating. As far as I know a heat pump should be at least twice that efficient than resistive heating. Great video overall! Enjoyed watching it

@Cracked1ce

2 жыл бұрын

there is also geothermal heat pumps that have a Coefficient Of Power (COP) of >4. what if you combine both of them tho. PV to power the heat pump, and solar water heater to heat the coolant circulating through the heat pump. this would maximize the heating ability of the solar water heater as well given there is a greater temperature differential

@superchuck3259

2 жыл бұрын

@@Cracked1ce Sounds like good ideas for future projects and videos. The guy in this video does a great job of being fair and explaining the actual real costs. Not some fake sales pitch. Also disclosing the issues of tax credits. Is it fair that someone that can afford a new car can buy an electric car and get a 7,500 dollar tax credit? Can someone making a mid to low wage afford new cars? even low end EVs 40,000 .

@hockeytops

2 жыл бұрын

Came here to say this as well. Solar electric + heat pump might be a closer race.

@MaxMustermann-sm4qu

2 жыл бұрын

Keep in mind, that adding a heatpump to the PV Array will increase the costs dramatically. So you should also expand the solar water heater Array to even out these additional costs. Than you should compare the outcome. And I think, you can easily quadruple the solar water heater array for the cost of a heatpump.

@apostolakisl

2 жыл бұрын

But that isn't an apples to apples comparison. The heat pump is capturing heat from the air which got hot because of the sun hitting the entire region of the country. The solar water heater is capturing heat from the sun that hit the box.

Enjoy your shower and dishes. I love all your videos, but mainly the distilling is what I like. Hope you have a great week.

As always amazing work. Ive heard of many of the things that you've done but only in passing and I enjoy every video

@TechIngredients

2 жыл бұрын

Thanks.

The system I'm currently designing for my house; involves a solar thermal loop, an insulated energy store.... and converting the heat to higher quality by use of a heat pump (powered by solar PV). As the heat source is above ambient, the expected COP should be far better than other heat pump solutions.

@CM-mo7mv

2 жыл бұрын

how does that compare to freeze storage systems (systems that take the heat from freezing the water) I am wondering if it would be suitable to utilize the heat from a solar thermal panel to remelt the frozen store during the day.

@DT-dc4br

2 жыл бұрын

The issue is with usable heat - on a sunny day, the same area of solar thermal would deliver more heat than necessary, but on less sunny days thermal alone can't create hot enough water for domestic use. The water from the thermal store isn't used directly (which avoids the complications of heat cycling sterilization) instead, the heat pump creates hot water on demand and can run from the grid (which in my locale is wind generation dominated).

@CM-mo7mv

2 жыл бұрын

@@DT-dc4br do you only mean hot water or heating. 🙈 maybe i have got you wrong. i was referring to heating, for which no sanitization would be required. I meant that a store doesn't need to be hot but can be just cold water and the heat pump can extract the heating from the freezing water in the store ... the store would be underground and otherwise unisolated and except sludge I don't see why it couldn't be open for external water. it's a concept sometimes used here in Germany (called "eisspeicher") ... anyway i still am not sure how to reliably turn the ice back into water for the next night except naturally melting. solar may be a suitable low energy option to supplement this. clarification: on our property there is already a water store that has been used differently in the past. however it is a little bit smaller and shallower than required so i would need to utilize it outside the bounds for a proper ice/freezing store and thus for very cold nights need a way of melting it back during the day... .

@DT-dc4br

2 жыл бұрын

@@CM-mo7mv Both space heating and hot water from the faucet. If it's just for space heating, then lower temperature water can be used with larger radiators or underfloor heating...but then again, for most of the summer months when the system is getting the most energy... there's not really a requirement for it.

@CM-mo7mv

2 жыл бұрын

@@DT-dc4br absolutely ... that's why i am referring to winter and colder months ... I don't know which climate you are in but if it is anything like in Germany with sometimes quite chilly winters looking into differentiation in space heating and faucet heating.... for the later i calculated it may not even be worth it to have centralized faucet water heating as the power needed for that and much higher temperatures to be up to code plus the return path and capacity for higher demand ( e.g. taking a bath) results in almost the same amounts of power needed than full electric on our usage pattern and structure ... however i did not calculate with added solar heat during summer time yet (thanks for that pointer)

Basically "Every energy conversion comes with a loss, so less of them = more efficient system" Episode 2137 But it's only true if you're using that electricity to generate heat. It's not popular but I've seen homes with both systems. Collector for heating up water (or helping heating entire house in the season) and next to it PV for electricity production (for light, fridge and so on)

@CaneSugarHD

2 жыл бұрын

I think electricity to heat is more efficient than the other way around

@Fallen7Pie

2 жыл бұрын

This is the way.

@juliuszkocinski7478

2 жыл бұрын

@@CaneSugarHD Well, yeah, by much

@zskk

2 жыл бұрын

Same here, plenty of places use both systems around Wadowice area.

@OxAO

2 жыл бұрын

Water to electricity I think you're talking about a Peltier device?

Excellent presentation. Very informative. I use solar panels to heat my water. I have dedicated 5.6 kW of panel's just to a large storage tank of 315 litres. I rely on the size of the tank to offset cloudy days of low output. It's not a perfect system but it's free hot water. I did consider a solar heater but roof space is not an issue and plumbing I prefer to keep to a minimum. I am a great believer in oversizing solar strings to offset low insolation day's.

I just found your channel a couple of days ago and really enjoyed it! Great content! Thanks for doing this!

You need to add a evacuated tube collector to the comparison.

@TechIngredients

2 жыл бұрын

We wanted to demonstrate a system you can easily assemble yourself.

@jmaus2k

2 жыл бұрын

It's pretty close with the 2 panels of glass. You could vacuum between the layers and put argon in to improve it, but it isn't going to make much difference until you are below 0.

@markfergerson2145

2 жыл бұрын

I wouldn't think the thermal mass of the enclosed air would make much difference. Remember he covered the water panel to prevent preheating it, and it still outperformed the PV panel as the air heated up along with the tubing and inside paint and so forth. If anything the enclosed air helps equalize the temperature of the tubing from end to end. Plastic tubing doesn't like temperature differentials very much. Speaking of temperature differentials- early panels used copper tubing, likely because it was relatively chap at the time and much easier to work with than stiff plastic (and is UV proof unlike the PVC tubing used in early non-copper versions). Copper tubing also transfers heat through its wall better than almost all plastics meaning it heats the water faster than plastics. It still needs a good flat paint though as it's a fair reflector of heat.

@Basement-Science

2 жыл бұрын

@@jmaus2k You cant pull a vacuum on such a large flat piece of glass, it will crack very quickly. If you just want to replace the gas in it, you'd just flush it with gas instead. Probably not worth it though.

@titter3648

2 жыл бұрын

@@markfergerson2145 The vacuum in the evacuated tube collectors is there for insulation. Just like in a vacuum insulated termos flask. Thermal mass has nothing to do with it. With the air in the collector like it is now you conduct the heat trough the air to the glass, and right trough the glass to the lower temperature outside. While with a evacuated tube collector you only loose the radiative heat out to the glass, not any convective or conductive heat loss like you get with the air filled collector. An evacuated tube collector would preform a lot better than the DIY collector he made here.

Being in Australia and trying to keep the heat out of buildings, I'd be very interested in development and testing of a DIY barium sulphate based paint. Lots of recent research showing benefits, but sadly no products on the shelf yet.

@lordjaashin

2 жыл бұрын

DIY is the route. don't make yourself dependent on corporate vultures and wait for them to rip you off with products that you can make your self easily

@pedrohenriquemorais4979

2 жыл бұрын

And if you live in tropical environment in this project you can eliminate the insulation (glass) and leave the tubes exposed. If I had to build one, I would use two reservoirs, one on the roof and one underground, to have thermal insulation on colder days or long rainy periods.

A+ intro music choice and cuts. Y'all are really doing good job. Keep it up.

Thank you so much for sharing! I really enjoy learning from your videos!

Before watching: absolutely a Thermal Hot water heater is generally far more "efficient" than Solar PV (as long as you want hot water, the energy source is much less convertible) It is cool how the e-glass acts like a thermal "laser-like" amplifier However on a cloudy day, its output drops to "zero" - well lets call it ambient, no gain. Our hot water heater gives "free" - (Cost well and truly offset) hot water for 90% of the year, by Solar PV, offsets the rest of the power we use (Cash Positive).

@garethbaus5471

2 жыл бұрын

An air source heat pump could give you a more comparable efficiency from the photovoltaics, but it would also raise the cost substantially.

@kadmow

2 жыл бұрын

@@garethbaus5471 : yes indeed, I haven't tested if the pump gain will make it as "efficient" as the hot water heater (a lot more complicated).... As previously stated, convertibility and tradability of electricity is the major benefit of PV... Also, the high price of Commercial Solar hot water heaters pretty much make them unattractive to install these days (PV plus heatpump hotwater heaters are most likely a better "financial" decision). Next for TI to show home grown PV storage for flexible dispatch.

This was a great video but I’m really looking forward to the air-crete videos you mentioned. In particular, I can’t wait to see your version of a foam generator and your foam formulae because I think bubble size will have a big impact on strength and longevity, and that is where other experimenters fall short. Their bubbles need to be like shaving cream instead of like dishwashing bubbles. Also, a comparison of Portland-based cements to others such as high-strength cements (aluminosilicate cements?) would be interesting. A challenge: can you cast an air-Crete “board” as strong as wood that’s low cost (minimal metal)?

@MyOldNameWasTaken

2 жыл бұрын

This guy right here is asking good questions. We need the answers

@rikulousb501

2 жыл бұрын

Very much looking forward to air-crete videos as well!

@TheKamiBunny

2 жыл бұрын

Would be interesting but I think unless it's GFRC that challenge would be impossible. Concrete holds well in compression, doesn't hold well in tension, while wood holds well in both. I think in theory if you were able to create air crete with a solid outer shell, like a kit kat bar, you might be able to create something similar, but it's failure form and deformation would be very different from wood

Having lived off grid in remote wilderness (Almost 8 years) I have some thing to add to the comparison. The hot water is plentiful in the summer but in the north where we have long cold winters, -47c only the Solar panels produce and they do so with easily as the lower the temp the more efficient they are. It all boils down to where you live and the weather you have. I Still go Solar year round..

@larryrobertstein7485

Жыл бұрын

That's my plan for the farm here in central Manitoba. Solar pv panels all year round. Hot water collectors in the warm months & wood heat in the winter. And wood fired water heating in the winter. Which helps heat the house.

@walksuponwater7261

Жыл бұрын

@@larryrobertstein7485 That is way to do it. I never was in a power outage because I had my own , just do 2 things, live within or below the power output of your solar system and keep the batteries from freezing( a fully charged battery will not freeze) my dad had a farm outside of Ericksdale Manitoba , small world.

I've done this experiment myself: When it is really cold out and you are wanting hot water, the temperature delta is going to highly favor the PV. The efficiency of it goes up as the solar cells get colder, while the flat-plate is going to fall dramatically as the delta between outside and water temp increases. Even evacuated tubes can no longer keep up.

@sibalogh

2 жыл бұрын

This is exactly what I am concerned about myself, otherwise, I would have done it also. PVs are also good to generate electric power for everything else as well.

You're doing the lords work. Im about to start building your foam speakers for me living room. Thank you for doing what you do.

@unionse7en

2 жыл бұрын

Lord Kelvin!

@chuzzbot

2 жыл бұрын

The what? Lol

@Jkauppa

2 жыл бұрын

no, you dont have to do work, at all, and not for people, at least

@Jkauppa

2 жыл бұрын

@Hot Sausage I dont earn my living, I'm given to

Ive been building my own insulated panels for the last week now, heres to hoping they work in -25c. Wish there was a good way to share the progress on them. Either way its nice to see a scientific approach to showing the differences on many different aspects of what is truly a simple yet affective technology. Great video and look forward to more.

@martindinner3621

2 жыл бұрын

You have a KZread account. If you're willing to post updates on your progress, we can check it out.

@DerptimeTV

2 жыл бұрын

kzread.info/dash/bejne/e4FnlbGPc6mxZso.html

@wilfredvanvalkenburgh2874

2 жыл бұрын

There is no reason that solar won't work at -25C, however here on Earth, in practical terms, that likely means besides cold temperatures, you likely also have low solar insolation (sunlight).

Great video. Thanks for all the time you have spend to help DIY .

@TechIngredients

2 жыл бұрын

Thanks!

Thank you for all the high quality content. I am constantly looking forward to a release of your videos. Please, please, please do a video on low temperature differential Stirling engines (like the Sunpulse 500) and maybe something on heat storage. Both will be great ways to add to the utility of a solar water heaters like the one you built. I would love to see your take on Stirling engine tech.

I really look forward to see more energy efficient assistance to deal with the cost of energy which has gone through the roof. My own experimentation with solar hot water heating suppressed me with the much higher energy gain as compared to the photo voltaic cells. Job well done Tech Ingredients. Keep the great videos coming for us all to enjoy.

I very much appreciate the fact that you mentioned the misleading effect that subsidies can have when it comes to making ecologically sound decisions.

@rcpmac

2 жыл бұрын

Wait! You are suggesting that solar energy receives government subsidies and fossil fuel does not! Not to mention the cost of remediating impacts on global climate change.

@pault151

2 жыл бұрын

The end user of any system typically makes their decision based on the apparent or adjusted cost to them. Each of the costs of material production, transportation, construction, and end of life disposal has an effect whether or not those costs are all reflected in the purchase price. Each level of government and industry may have fees or taxes or other adjustments applied that change the cost to the end user. Life cycle analysis is one name for the discipline that studies all of the actual costs of the use of materials and their impacts on society, the world, etc. Solar cell production and acquisition are affected by various levels of price support, subsidy, taxation, fees, etc, just like all of the other inputs to this system including the petroleum and plastic companies that create the tubing.

@rasen84

2 жыл бұрын

You people are confused about the intention of the subsidies. You are right now currently not actually living a carbon emission free life. The free market says that you deserve to guzzle oil and it will be cheap. Living a zero carbon life is just more costly or inconvenient. State subsidies are there because it spreads out the costs evenly. That's good public policy. The negative effects of carbon emissions are collectively experienced so the costs to avoid the negative effects must be managed collectively as well.

@chrisoddshoes

2 жыл бұрын

@@rcpmac No. I don't see how my comment leads you to think this. It could be subsidies for fossil fuels, wind farms hydro dams etc. I'm simply saying that to make reasoned decisions we need all the facts and that they are frequently hidden or obfuscated by governments and other financially interested parties.

@wilfredvanvalkenburgh2874

2 жыл бұрын

@@rasen84 The "free market" price of oil is an Illusion. I believe you understand that, but was not clear from your post. Gas and oil can be as high as $300 per gallon (combat zones), but the cost of burning oil, and the waste of plastics produced by oil, maybe the cost of our planet.

Love your shows especially the ones on distillation!!!

An enjoyably informative video as per usual! Just one thing: The PV panel table was slightly lopsided --- away from the sun --- perhaps reducing a few watts. That said, producing heat from sunlight is easier than producing electricity. In equatorial regions, it's quite possible to even use the heat so collected to drive a steam turbine (I've read of and seen videos of companies doing this in places like the Middle East). But, for most places and especially in the upper latitudes, having both PV and heat collectors is best --- heat collectors for heating and PV for electricity (which can also be used to drive the pump in the heat collector).

now use a heat pump with the pv panels :D and yes cost goes up but so does efficiency :D

@lordjaashin

2 жыл бұрын

"cost goes up" then the comparison isn't fair. everyone knows if you want to increase efficiency then the costs go up. so obvious

@niklasxl

2 жыл бұрын

@@lordjaashin yes but over the life of the product(s) it might be cheaper and also with a heatpump with a cop of 5 you get a lot more out of it. so a test of the roi with a heatpump involved aswell would be interesting

@lordjaashin

2 жыл бұрын

@@niklasxl the problem with heat pump is it needs to be run on grid electricity. it cannot run on PV panels unless you have huge array of panels, battery banks and MPPT controller. it might be more efficient than solar heater but what benefit is the efficiency when its high price turns away majority of customers?

@davesmith9325

2 жыл бұрын

@@lordjaashin it's totally fair if you want to.maxomimisr heat and have a fixed area but unlimited funds. you also need to consider what the costs really are, if you have a large installation, say a 10kw heat pump, that's a huge number of panels, the extra cost of the heatproof over 25 years isn't so much. On the other hand if cost is the limiting factor nit space for panels, consider that for say 2500 bucks you can get a different area of thermal vs. Pv panels.

Keep in mind for the taxes, that solar panels would likely be more competitive without tax subsidies & incentives if gas and oil hadn't received many such subsidies as well (or at least received them in the past, furthering their development and infrastructure). I agree though and think we should get rid of all of them rather than fight fire with fire. Very cool video! I'm really looking forward to more! I also agree with other commenters that I'd love to see a hybrid panel which uses the fluid to cool the PV panel

@flexairz

2 жыл бұрын

Thank goodness for oil. As we can not live without it. All you do, eat, sleep, medication, products, cars, and whatever is thanks to oil. This is something the oil haters forget.

@hngldr

2 жыл бұрын

@@flexairz True, but we can recognize how much its helped us while also recognizing the need to move on.

@tfwmemedumpster

2 жыл бұрын

Europe hasn't had any incentive on oil and gas for decades. Last time there was anything like that was in the 70's with the energy crysis. Solar panels still only make sense because of heavy subsidies. I'd love for renewable energy to become viable. I mean it's free energy for crying out loud. But they aren't there yet. Nor is there any sign that they'll be ready by the time politicians want to phase out fossil fuels. It's foolish to preach for the phaseout of fossil fuel before we find a suitable replacement. Which to be fair nuclear power would be a more than capable replacement but if people don't want to use it then we'll have to wait for something else to be developed/perfected

@xapemanx

2 жыл бұрын

@@tfwmemedumpster Oil and gas is renewable, it a mineral that regenerates from subsurface pressure of carbon and hydrogen (organic compounds only means it has carbon it in) this happens under ground to form complex hydrocarbons, before we started harvesting oil, oil would literally flow up naturally out of the ground.

@234fddesa

2 жыл бұрын

it's less that oil and gas have been subsidized, which they have in some countries (read: globalization incentivizing oil and gas), and more that oil and gas companies can outsource costs onto the public. The cost of climate change is something that can be outsourced, the cost of people dying from lung cancer, because they lived too close to the coal plant, that's a cost that's outsourced. The incentivization of solar is meant as a way to combat the outsourcing, the "hidden costs", carbon tax is a way to combat global oil incentives.

Thanks for the comparison that I always wanted to know before.

Great comparison and explanation of what you did to make it more efficient.

Would like to see you build a phase change energy storage unit to go along with your panel! Thanks for the video, great to see a comparison!

I got really into this a while ago and did some research on it. There were a few things that made me decide PV was the way to go. #1. You use heat pumps to heat not resistors. So you can get a LOT more efficiency out of modern heat pumps & these things are going to be very reliable if you want to be able to occasionally use the grid to power water heating in the winter etc. #2. You mention some of this at the end, but complexity in the solar heat collector for dealing with freezing and something you didnt mention - over heating. Over heating can be a big deal if you arent drawing the heat out for a few days during periods with a lot of sun. Industrial systems have pretty extensive solutions to deal with this that would add some cost to a home system if implemented. There was a great article i read summarizing all this too - if yall are interested i can try to dig it up.

@rotemfux3778

2 жыл бұрын

hi i will be glad to get it

@garethbaus5471

2 жыл бұрын

I would be interested in the article.

@TheRainHarvester

2 жыл бұрын

Yeah I had all materials to diy a thermal heater, but freeze, over heat, and a lot of potential leaking made me decide solar electric was more practical.

@Jehty_

2 жыл бұрын

A DIY over-heating solution shouldn't be to difficult. Just a thermistor, two electric valves and a microcontroller. And anti-freezen should prevent freezing, shouldn't it?

@LucidTactics

2 жыл бұрын

@@Jehty_ Yeah you need to vent it if it over heats, and I think you need to vent it near the top of the whole assembly. If you use anti freeze, you also will need a heat exchanger to move the heat from the antifreeze solution to your house water. These problems are certain solvable, but they add cost and maintence issues, and you might not want cheap DIY things for a house you may sell... now that all might be fine but... When you factor in the heat pump hooked up to PV giving you 2-3x the amount of heat generation as a simple heating element... PV really just makes a lot more sense.

Excellent video, thorough methodology and really helpful. I had no idea one could make one's own solar water heater panel so cheaply! Thank you very much.

I originally determined to skip to watch just near the end. But turned out I keep scrolling back to a bit earlier that where I started again and again as you keep giving some very interesting info that I have to scroll back to see where it come from Dang what a channel

@TechIngredients

2 жыл бұрын

😀

You mentioned making a video about Aerated Concrete, which got me thinking that you could also make a video on refractory/firebricks. These brinks are usually pretty expensive and I know how you guys love to diy solutions that are higher performant and cheaper than what is commercially available

@piratewhoisquiet

2 жыл бұрын

SECONDED

On a similar theme - I find vacuum solar water heaters extremely facinating. The fact that you can get an almost boiling water out in the winter, when it is easily -15 C outside is amazing.

An excellent how to on a topic I know nothing about. The difference in collected energy was surprising, thank you for all the effort to prove it.

Very detailed and informative. Thank you

Wonderful video! I'm looking at building a hot water shower using a solar water heater at my off grid cabin (located on an island in the woods, in Sweden). This just convinced me even more that it's the right route to take. Though I will probably add some small PV or Piezo element to run the pump - since it only needs to circulate during daylight - when the heat is produced and than just let the hot water be in some form of isolated tank. With a Piezo one could also use the pump while the box is warmer than the outside, or double up with a water heater around the chimney from a sauna - or something like that. Great tips on cost savings and where the most money can be saved. Keep up the good work, still loving the channel. Greetings from Sweden!

@koma-k

2 жыл бұрын

There are combination solar panels available, that do both PV and thermal in one. One positive side effect of this is that the PV panel is kept relatively cool, since high temperatures degrade performance somewhat. I've no idea if there are distributors of these in Sweden - I've not found much in Norway - but there are several companies in France, Austria etc. making such panels.

@evilkoala81

2 жыл бұрын

@@koma-k Great tip! Thanks a lot! Will look into it.

@wilfredvanvalkenburgh2874

2 жыл бұрын

@@koma-k I've not heard good things of these combination panels. What was said is that the underlying thermal panels won't get hot enough and may leak, thereby damaging the PV. Your results may vary.

@wilfredvanvalkenburgh2874

2 жыл бұрын

Have you considered a Stirling engine? Back in the 70's there was much talk of a thermal pre-heater called The Copper Cricket. I remember it was Popular Mechanics or Popular Science magazine innovation of the year. There were big problems in balancing the system, that required factory trained technicians. I haven't seen much of it since.

@evilkoala81

2 жыл бұрын

@@wilfredvanvalkenburgh2874 Can't say that I have, but I know of it. Probably a bit overly complex for this application, concidering others (less technical people) will use the system frequently, I try to have it work as "domestic" as possible - and automated. As far as I can remember, a Sterling engine needs a little help starting. A PV or Piezo just delievers power to an electric motor. Quite self contained system.

I hope you get a chance to build a pop can heater. I built one at 4x8 ft. and it tripled the ambient air temp outside. I also moved the air through it with a 5 in. computer fan driven also by a solar panel (12in.x16in.x7watts). It was easy to make with simple materials. I used a 1/4in. 4x8ft. sheet of plywood for the base. I made a 4in. side using 1x4in. around the perimeter and lined it with chrome bubble wrap. The top was covered with a clear plastic normally used to help insulate windows, and a second layer placed over top of wooden bows of wood cut to 1/4x 1in. to give it a better insulating factor. The bows were slightly longer than 4ft. so they had about a 3 to 4in. lift in the centre to hold the second layer away from the first. The pop cans were easy to prefabricate by using a can opener on the tops and a hole drill to open the bottoms. I used 100% silicone to glue them together placing them in a long piece of angle iron to keep them strait till dry. As it is currently outside in the snow, I cant remember how many rows I put on each side but it was an uneven number, like 6 rows on one side and 7even on the other. Now don't be confused when I say there are two sides because what had done is built a 4x4in. plenum at each end four ft. wide at the top and the same at the bottom but it is divided in the middle but only in the bottom plenum. So now the air comes in through a 5in. hole drilled in the bottom on one side of the split plenum it then goes up through 6 rows of cans held in place by 2in. holes cut in the upper and lower plenums. Then comes out the top into the upper plenum and goes across and down the other 7 rows into the bottom plenum then out through the 5in. hole and is exhausted out the 5in. fan. In an country where it gets extremely cold in winter months, this unit will work very well as supplement heat, as long as there is sun, which I don't get through the winter months up here in Canada. Ya so it was a bit of a waist of time. Truth is I just have too many trees and not enough sun. Thanks for all you cover in so many videos, sincerely Bill Campbell. PS sorry if I misspelled anything.

Informative video and I appreciate hearing your opinion on subsidies. It's a topic that a massive number of people don't understand.

Absolutely love this channel!! Thanks :)

Thank you for this video. Our combined knowledge comes from our combined experience, and your experiments add to the pool. It would be nice to see the final numbers, specifically time and temperature gain. It's hard to conduct such experiments without any bias, for example: the hot water panel is insulated, and thus prevents heat loss from the water that circulates inside it. On the other hand, the pipes leading to and from that panel are not insulated, so there's unmeasured energy loss there... hopefully all the small biases cancel each other :) I wonder what we'd find out if there was another panel which combined both approaches, i.e.- heating water with the excess heat from PV panels, which uses more of the light's spectrum, and at the same time cools the panels, which increases their efficiency, would the extra work and cost be worth it in comparison with the simple water heating panel?!? Also, I think such experiments need to account for the intended use of the system, since converting one form of energy into another, (electricity to heat, and vice versa), involves some energy loss, plus an added cost/complexity to the system itself, and to its maintenance. Regardless, your experiment seems to show that the gain in energy harvesting efficiency is far greater than the loss during energy conversion. Thanks again.

@w8stral

Жыл бұрын

Umm dear idgit, there are NO PIPES to a PV panel... there are WIRES. The solar thermal collector is at the disadvantage.

You covered a bit the topic of harvesting radiated energy. In the previous videos you covered the topic of the cooling by liquid evaporation process. What about the cooling process by emmiting far IR radiation into the sky? You mentioned the film that alows the visible light to come through the film but doesn't release the IR outside. Is there a film that releases far IR instead of light/near IR?

Really enjoy your vids of experiments you perform. What kind of benefits would come from installing the mirrored doors like you have built on the solar panels? Thank you for your time

Such a good good teacher. Thank you.

Another great video! I'm sure you've thought about this, but it would be interesting to do a DIY Sterling engine build (or something similar) to see how efficient electricity production could be from the heating panel. It certainly won't match the PV panel efficiency, but could be worth considering once you take into account all the factors

@claws61821

2 жыл бұрын

It might! We can't really know without actually getting the Sterling engines or other thermoelectric generators into place and testing them in real-world situations as in the video above.

First thing: no MPPT on the solar panel? Second: if all you're interested is heating water, running an air source heat pump instead of a resistor bank off PV would have gotten you much better performance.

@pugnate666

2 жыл бұрын

First: heating is by definition 100 % efficient, aka. the resistors are converting all the energy they get into heat. Second: We're making hot water here, not hot air. But, you're right. A heat pump beats everything in terms of "efficiency"

@areuaware6842

2 жыл бұрын

Agreed.

@user-fs3dg1po2z

2 жыл бұрын

@@pugnate666 "We're making hot water here, not hot air" You've never heard of a heat pump water heater?

@Ender_Wiggin

2 жыл бұрын

@@pugnate666 A heat pump can be 400% efficient compared to directly heating water with electricity

@pugnate666

2 жыл бұрын

​@@Ender_Wiggin my words exactly

Excellent test. Very useful information.

Brilliant ! I've been considering how to build a solar water heater for off-grid use. Thank You . . . AGAIN!

it would be super interesting to see this redesigned to use a fresnel lense

@theevermind

Жыл бұрын

All that matters is the amount of sunlight, which is proportional to the area. A lens would only help if that lens is bigger than the solar collector and then concentrates the light onto the collector--in which case you could simply make the collector bigger at probably lower cost.

@sandyt4343

Жыл бұрын

I have a four foot square fresnel lens and although it concentrates intense heat in a very small area, it does nothing to the area outside the focal point. Also it is very directional and has to track the sun or it doesn’t work. You can melt lead or even concrete with it but it’s not practical for many other purposes.

@benjaminbarr8714

Жыл бұрын

@@sandyt4343 Maybe mirrors would be a better option then

Hello! First of all, thank you for your amazing content. I am a big fan. Aside from that I work as an electrical engineer, building solar power plants. I am not sure if you adressed that on your video, but solar panels have an "optimum" operating point, that changes over time with solar irradiance, temperature and other factors. Normallly a controler is used between the panel and its load, either with PWM or MPPT tracking. Keep up the good work! Big hug from Brazil! 😁

@TechIngredients

2 жыл бұрын

I didn't cover that directly, but the optimal resistance for these particular panels under these conditions was measured and that is the resistance we used. An MPPT controller will accomplish the same thing automatically as the conditions change.

@besamjohn

2 жыл бұрын

Thanks, I was wondering the same thing.

So glad I ran into this video. I was wondering about just this idea. Have to see if you have a video taking the heated water into electricity.

Great job! We are at Capricorn tropical line. A few decades ago (1970's energy crises), my dad decided to build a solar water heater. It was a interesting introduction to energy balance and engineering for me, at high school at the time. The colector had 2 by 4meters, it could suply with very hot water, 85oC, enough for the needs of a 6 person house. We had to be carefull with hot water burns.

It would be an interesting comparison to compare a solarium/solar greenhouse to an equivalent sized solar collector coupled to hot water radiators as to home heating capabilities. As always, another excellent video!

@redstone1999

2 жыл бұрын

For greenhouse during summer time, you need a cooling system instead of heating. Cover water panels during summer time. Have an outside cooling pipes buried or in windy shady area. Just make sure it is well drained before freezing temp. start.

With an eye towards maximizing the use of a rooftop, how much heat can be extracted by water-cooling the photovoltaic panels from below? My understanding is that the PV panels are more efficient when operating at a cooler temperature?

@tc5963

2 жыл бұрын

To start it would work as good as both of the system but as the water under the pv panels heats up the panel loses efficiency due to it warmimg up past whatever temp it would have been with ambient passive cooling

You are awesome. You also have a good camera guy and mix. Good job all around

As a farm kid who burnt his face MANY MANY times trying to get a drink from the garden hose in August.. I was very happy with the results of this test. Planning on building a thermal battery myself now. The double pane + e-glass system you have there has to increase the efficiency dramatically. Ill be doing the double pane just for the sake of getting the most from my system, but i'd love to see a comparison of the double pane vs single pane system.

"Society cost" thank you for giving me that name, totally understood what it means, never knew this concept had a "phrase" , very powerful. 23 minutes well used, thank you for this education.

@RogerFrigola

2 жыл бұрын

"societal cost"

Thanks for sharing, Always find your videos interesting and well made. From a solar hot water sight a few years ago that sold the vacuum insulated glass tube water heaters. They were located in Binghamton NY and said the infrared sun light makes it thru the overcast winter sky and makes hot water year round. Always thought it might be interesting to see if a solar hot water driven sterling motor powered generator might stand up to a photovoltaic in the winter. But secretly I figure if anyone can build a residential sized thorium LFTR it’s you guys.

@mangeload

2 жыл бұрын

any ideas on inlet pipe freeze prevention for off grid use?

@tbix1963

2 жыл бұрын

@@mangeload they only have water in the pipes and collector headers, typically they use a glycol mix with a heat transfer at the water storage tank, I believe the glycol not only prevents freezing but increases heat transmission. They also have a gravity drain back tank with the pump driven by a solar panel, if there is enough daylight to run the pump it’s assumed the heating panels are also ready to go.

@mangeload

2 жыл бұрын

@@tbix1963 Thank you for your response. I have an idea (im sure im not the first to think of it) to run a low watt (3W/foot) 12VDC thermal pipe trace on a thermostat that controls when the trace is actively heating, which is also thermostatically activated so it will only heat where / when needed. The purpose of this setup is to prevent pipe freezes while minimizing power consumption in an off grid system. This will be efficiently accomplished by avoiding an inverter's idle draw, and maximized by running low consumption DC pipe trace & bypassing inverters altogether. This should be a practical and inexpensive way to prevent pipe freezes (much cheaper than new plumbing) & will provide a small backup supply in case of emergency power outage, that can be easily built upon. And I'm doing it all for between $500-$600. Here is my planned setup: 100 amp hour deep cycle battery, 40amp MPPT charge controller, 100w mono panel, cables & wiring, connectors & fuses, 400w inverter, 6 - 8 feet 12VDC thermal pipe trace (@ 3w/foot 18w-24w), thermostat, pipe insulation, & maybe a battery bank status monitor. Future plans also include 600w total solar panels combined & 4 x 100ah deep cycle batteries, & a 1500w pure sine inverter. What do you think? Any advice or suggestions will be appreciated.

@tbix1963

2 жыл бұрын

@@mangeload maybe I misunderstood your problem, you have a water source that your afraid will freeze? If you have plenty of water that is pressurized a cheap solution would be a freeze miser water valve. Under freezing conditions it allows a small flow of water keeping the pipe above freezing temp for the price of some water. Freeze Miser, can be found on Amazon for about $30. I’ve seen it used by ranchers in subzero temperatures to water cattle from garden hoses lying on the ground. As for your electrical solar solution, I’m no expert but it sounds like your possibly going in the right direction. I’ve used heat tape before to winterize pipes in a drafty cellar before but always found them a bit unreliable, compared to letting the water trickle. Good luck with your project.

Absolutely love your videos, as I understand everything you cover, at least regarding this one, particular video. That is all, for now

Glad you talked about disposal.

I've looked at making these. I would probably put some form of insulation, maybe spray foam, to help with the cold colorado winters. I would like to see how the antifreeze would work against regular water or salt water if you rather not use antifreeze. One downside of these is the time it takes to heat the water. 15L isn't a lot compared to a standard family water heater. I would be interested how quickly water heats in an open system as opposed to the closed system you made. These are very popular in Greece. They are on nearly every roof out there.

@a1nelson

2 жыл бұрын

These techniques and systems are not just at lower latitudes. Heat (and “cold”, collected during winter) storage tanks are also common in the Netherlands - using large temperature range liquids - or so I was told when I was doing (unrelated) engineering work there. I wish I would have asked directly, but my interpretation of this at the time was that the systems were probably using ethylene or propylene glycol. Superior insulation is obviously, absolutely essential. The way it was explained to me, with the system continuously being heated and with the volume being large, the efficiency and utility ends up being quite high. Naturally, energy is still harvested at some rate, be it faster or slower. But, I guess the overall point is that it can be practical, once the scale of the system is sufficiently large. Although I have no information to substantiate this, I suspect that systems using this technology are also using small demand heaters (electric or natural gas) to boost the tank temperature water up to that which would be used by, say, a bathroom shower. Edit: …along with antifreeze/tap water heat exchangers, if that wasn’t already obvious. (Maybe the demand heaters and heat exchangers can sometimes be integrated? I should look that up…)

@a1nelson

2 жыл бұрын

Typical antifreeze/s offer a significant advantage for heating/cooling systems that use pumps or convection to regularly circulate water: they significantly reduce corrosion/galvanic reactions. Even though those reactions are fairly slow, they do create abrasive precipitates (for example, aluminum oxide - commonly used to make sandpaper) that can easily cavitate, and therefore destroy, structures in the system over time. I’d stay away from salt water all together, for this reason. Although I thought it would, we found that using distilled water (as opposed to municipal water) alone doesn’t help all that much.

If you're putting the solar thermal system onto your roof, remember to account for the extra weight involved. You might need to reinforce the roof rafters.

@julianbello8376

2 жыл бұрын

My roof is cement, but thanks nonetheless

@harveybc

2 жыл бұрын

True, but don't forget most of the water will be in an insulated storage thank that's not on the roof. A 100 feet of 1 inch ID tubing would only hold a bit less than 4 gallons on water so you are only looking at about 35 pounds of water.

@tarstarkusz

2 жыл бұрын

They suck. Solar hot water was very common in the US before natural gas and oil and to a lesser extent bottled propane were cheap and available. They don't really work very well unless you live in the deep south and have lots of sun available most of the year. A lot of the efficiency of the system is lost because of anti-freeze. Direct heating is just a lot more efficient than adding a heat exchanger. They just aren't very good at transferring low grade heat (when there is not a very large temperature differential between the antifreeze and the water you are heating.)

@falsedragon33

Жыл бұрын

That's pretty silly. I have 13 12ft by 4ft solar panels to heat my pool. They don't weigh much full. If you are scared of your roof, the thing to worry about is how much things contract and expand. Even a rubber boot will wear a hole in shingles in under a month. A bit of flashing under contact surfaces solves that.

@brucesibbitt9949

Жыл бұрын

@@tarstarkusz your generalizations are misleading. I have a well designed solar water heating system which uses a heat exchanger and propylene glycol antifreeze and water mixture, in Ontario, Canada that continues to work well 14 years after installation. On the other hand, I'm pretty sure that there are poorly designed products out there that do suck but that doesn't mean the technology itself is the problem!

Excellent video as usual!

Love your show! I’ve always wanted to try this experiment but have lived in high rise styled apartments over the past 25 years; never had the space. How much better would the PV panel have preformed had you added the tracking polished aluminum reflecting wings? surely it have boosted it quite a bit? Love this show!!!!

how is the channel not past 1 million? I've been watching for a couple of years already, love the passion for information you guys have!

@polymathpark

Жыл бұрын

I think it's because it's not flashy like other engineering channels, and the videos are long format. Sucks, because it's so dedicated, humble and thorough, it gets less views and subs

@noneedtoknow5315

Жыл бұрын

Most people have learning beaten out of them by public education. It has to be flashy and not require cognitive thought.

13 seconds in and I just punched the air and yelled "YES!!". I'm glad this topic will be explored in the level of detail and care you put into your projects.

@AtlasReburdened

2 жыл бұрын

@@1newme425 Where did you get the jump part from?

A great scientific comparison, thanks for all of your hard work which went into this

I love your channel! You explain everything so clearly, but provide absolutely every minute detail. This is a really nice test, particularly as the solar water heater is not necessarily the most optimised and solar PV is so much more popular. You've also made it really clear for anyone who doesn't understand energy as you have a direct comparison in the water temperature rise I've seen your recent videos where you add cooling to the back of PV panels, but it would be nice to see how much the PV would reduce the solar water heater output, either if simply placed in front, or if the 2 were integrated. I know there would be so many variables with a test like that, e.g. as the air temperature would affect the PV panel temperature and reradiated infrared would be lower at lower temperatures, etc. Evacuated solar water heating tubes are reckoned to be the most efficient domestic solar energy harvesters and can operate at lower air temperature. It would be nice to see a real world comparison between them, PV and the DIY solar collector you show here.

It would be interesting to see an experiment where you want to see how much stored Kilowatt you can achieve, between the two sources you have, which is PV panels verses solar water heating which is converted to electrical energy. What I notice in your experiment, is that the solar modules needed to be placed correctly as to the azimuth angle to the sun to optimize the efficiency of the pv array. I have both systems at my home, where I am totally independent from the grid for both electricity and water heating. Each on their own are excellent in their own application. Your experiment was very interesting, and makes one think. Thanks.

@randoshanks

2 жыл бұрын

That’s what I’m thinking!!

@MrArnih

2 жыл бұрын

Hey Nicolaas, i see what u mean, but, wouldn't putting the solar water heater also to the correct angle to the sun make it more efficient thus giving the same results as the video? IDk it's just a possible asumption, although maybe due to the way a PV panel its built the angle affects it more than i think idk or event maybe once the water heater stars to reach a certain temperature it just reaches a limit where's maybe the PV panels start to have advantage. (Also the water heater is slightlly bigger in the video but i think he said he had it into account) Sorry for my english im spanish.

I was searching for "e-glass" but found it to be the high electrical resistivity fiber type glass for electrical insulation. Then I learned something: The reflective-coated thing is called "low-e glass" and there are two very different types of it: - "Passive Low-E Coating" is an Indium Tin Oxide layer designed to gather as much heat from the sun without letting the heat out - "Solar Control Low-E Coating" is a thin silver layer designed to improve thermal insulation both ways, it is used in hot climates where it doesn't let too much heat inside. The former is obviously the best for this project, while the latter might even be counterproductive. This is quite an interesting topic, it would be interesting to see how it performs when it's cold outside or when the water gets really hot. How much does power vary over temperature (difference), at which point is it the same as the PV panel. As for the PV, its efficiency is much more consistent with a constant voltage than a constant resistance load. Around 75% of the OCV. Anyways, great video, these things always get me curious!

Awesome detail and explaining merits and demerits and true costs

That was awesome. Thank you!