that is a really nice demonstration mate - loved the video - cheers

@texasprepperprojects

6 ай бұрын

thank you!

@izaksmith538

11 күн бұрын

Right!?- I saw a video with a guy doing a pool heater with passive solar; his whole setup was well thought out (he was probably an engineer), but when it came time to measure the temp of the water coming out of the heater he excitedly showed of his candy thermometer that measured up to 450F.

Don’t ever stop teaching KZread. Bought you a coffee because you are detailed, don’t waste time, and know how to state your theory or intent right up front.

@texasprepperprojects

2 ай бұрын

Thank you!

Years ago, my unsold yard sale crock-pots got packed with play sand. Strategically placed, I've supplemented my winter heat ever since 😊

@texasprepperprojects

14 күн бұрын

Oh wow!

When was the last time you saw 250°F water? One BIG benefit of sand is that you can easily go FAR above water's boiling point without a pressure vessel, giving you a way to offset the difference in heat capacity. Imagine 1000°F sand!

@texasprepperprojects

2 ай бұрын

agreed!

@so_what_else_is_new

2 ай бұрын

Exactly!

@texasprepperprojects

2 ай бұрын

@@so_what_else_is_new thanks!

@clivestainlesssteelwomble7665

2 ай бұрын

The only issue with this is ..sand for building is globally a resource under pressure. So best do some careful research.... as I told my gardening ex all soil is not mud..😂 Find out what's available and watch out for the unexpected.

@texasprepperprojects

2 ай бұрын

Yup

Good DIY demonstration of a sand heat battery. As you said water has a higher specific heat capacity than sand approx. 4200 J/kg/K to 830J/kg/K about 5 times. So 25 kgs of sand heated up by 500 Deg C would store 830*25*500 = 10.3 MJ not a lot, but the great advantage is it can be easily scaled up. Great video.

@texasprepperprojects

2 ай бұрын

Thank you+

You miss one point. But it’s otherwise a perfect demonstration of the principles of sand batteries. The purpose of making a battery is to store energy for you to use later when you want to use it. So putting in an insulated container is how you retain the heat for later and pipes would allow you to extract the energy when that time comes. Nice vid.

@texasprepperprojects

2 ай бұрын

depends on where you put the sand container. If it's INSIDE the house, then DON't insulate it. If you put it OUTSIDE the house, then DO insualte it. You can't cheat thermodynamics

@jhornett

2 ай бұрын

I was thinking about this as well. Presumably while the sun is out there is enough heat for the greenhouse and storing the heat for the night or for cold cloudy days will be more important. Maybe the mass needs to be big enough that it never hits a peak and levels out. That way the maximum amount of energy is stored and can be released more slowly as opposed to getting a max temperature for the watts available. I like the simplicity of the setup and it's a good video!

@texasprepperprojects

2 ай бұрын

@@jhornett thank you!

@ursodermatt8809

2 ай бұрын

seems to me using water is a lot more easier and makes more sense.

@pchris6662

2 ай бұрын

@@ursodermatt8809 Water brings with it a lot of complications. It boils at 100C so you don’t want to go beyond that unless you are ready to deal with steam and pressure. Corrosion. Leaks. Sand on the other hand can keep absorbing heat all the way up to ~1700C. The name of the game in batteries is getting maximum storage capacity out of a given volume/mass. A very elegant solution if truth be told.

you could wrap that pot with copper tubing to make a fluid heat exchanger for haeting a soaking tub, radiant floor heating etc

@texasprepperprojects

2 ай бұрын

It all depends on if you have the bucket inside or outside your house

This is such an awesome project. I have no need for it but I want to make one anyway. Thanks for the video!

@texasprepperprojects

2 ай бұрын

Thanks for the comment!

Excellent! Simple, straightforward. Your right. Unnecessary complexity reduces cost effectiveness. You cant make energy, you can only move it.

@texasprepperprojects

5 ай бұрын

Well said!

I love the physics you use and explain,easily understandable to anyone. From "the physics professor"

@texasprepperprojects

2 ай бұрын

Thanks!

For optimal energy transfer from solar panel to resistor (heater) there should be done some trials with various values of resistors. Here was used, arbitralily, resistor = 15 Ohm. Since the solar panels have high internal resistance, and there is a voltage drop when they are loaded, first there should be measured voltage of 2 panels in series without load, and later adjusted the resistor to such value as to get the voltage under load close to 1/2 voltage of open circuit.

@texasprepperprojects

Ай бұрын

thanks

I am probably going to try a similar experiment for this coming year (2024). Of all the questions and suggestions I’ve seen here, no one seems to realize that water can’t be heated above 250 degrees F or it just boils away. But sand can be heated to 1500 degrees F! I’m thinking I can build an insulated box outside the back wall of my 12x12 greenhouse to contain the sand battery, let it charge all summer long, and direct-connect the battery to the greenhouse with an insulated 3 or 4 inch PVC pipe. There would be a small fan that would turn on when the greenhouse inside temperature drops below 50 degrees and off at 70 degrees to recirculate the air from the greenhouse around the sand battery to reheat the inside of the greenhouse. The battery would certainly lose heat during the winter but it would still recharge during the day whenever the sun is shining to create the electricity for the heater element. Plus it would amass all that heat throughout the summer months and begin the winter with a surplus amount of heat energy stored in the sand. By the end of the winter I’m sure there wouldn’t be much surplus left - if any at all, but as the spring moves into summer it would start recharging all over again. I just want to keep my winter crops from freezing. I’ll have to see how this goes. I may need to have more than 1 or 2 batteries to make this last, but once I’ve got the numbers down it’ll be free heat all winter for my greenhouse. See “Polar Night Energy” for an example of how they are heating homes with a sand battery. Of course it’s just a matter of scale. My challenge is to find the right scale for my 12x12 greenhouse.

@texasprepperprojects

2 ай бұрын

I think you are much better off using a small pump to circulate water through black tube on the roof and heat up 55 gallons of water or more. Check out my recent videos on this.

This is cool! Thanks for sharing.

@texasprepperprojects

6 ай бұрын

Thanks for watching!

Thank you. best and easiest demo.

@texasprepperprojects

2 ай бұрын

Glad it was helpful!

I do something similar with flat-plate as well as focused solar using oil. Works great year round. Won't freeze.

@texasprepperprojects

13 күн бұрын

Nice!

Nice proof of concept.

@texasprepperprojects

4 ай бұрын

Thanks!

Love this idea, I will be doing this come fall..

@texasprepperprojects

Ай бұрын

You should!

Best explanation ever

@texasprepperprojects

24 күн бұрын

Thank you!

good project

@texasprepperprojects

2 ай бұрын

Thank you!

Great presentation. Basic Principles thought out logically that make good sense. I think this idea (concept) basically "as is" has so much potential for future development. The biggest obstacle being the effectiveness of today's Solar panel technology. As that technology improves (and it is) I can imagine scaled up versions of this basic design will be in a future niche of its own. Eg. Consider a building, with a sand filled, central back bone wall. Perhaps that same wall incorporating a "closed water" system with under ground heat sink. // Switch on/off between seasons.

@texasprepperprojects

21 күн бұрын

Glad it was helpful!

Thanks!

@texasprepperprojects

2 ай бұрын

Thank you!

Hi thank you for that. It is good that you show us how to do it, however. I have been using immersion heaters as dump loads. To control our wind turbine. Over the years we added 5kw+ of Solar pv. The base voltage is 120vdc and the Dump load voltage is 138/9vdc into two tanks total capacity is 500ltrs +, each immersion is 2 kW. They are stepped to brake the WT seconds apart. It works very well with no problems since its installation in 2008. I would not dare tell you what to do but an accumulator of capacitors or batteries would give you a much better power range. You were working in the full Power of the Texas sunshine and if your sunshine range dips to 66% you will get no heat. With capacitors or batteries or both between the panels and the sand battery it will produce much more over a longer period. 55 years ago, they installed storage heaters in our dwelling houses. Some were 3jw.. They used economy 7 to heat the elements but the material used to store the heat were canisters of 4mm limestone chipping., dust free. 3 canisters approx 200mm in width sq and 500mm in depth. Made up a 3kw unit. Later on they used a fire brick of sorts. This is a much discussed item in renewable energy forums. Keep up the good work. Cheers.

@texasprepperprojects

2 ай бұрын

thanks!

Neat idea 💡

@texasprepperprojects

Ай бұрын

Glad you think so!

Excellent! I would just put some fence around as a shield so not hit the hot pan by accident. I think if you can build a simple insulated box to put it in and out, it can hit peak temperature much faster. A smaller version with an insulation box would be great as a camp tent heater, where need less power from a smaller more portable panel, and will only use the heat at night. It's so simple any camper can do it!

@texasprepperprojects

5 ай бұрын

Thanks

@user-uv2yl6cm4c

3 ай бұрын

Campers burn rocks and use those as heat for the night. You could also use a metal bucket of sand and use that as a heater for the night as well.

I live in the south of Sweden. Our climate is similar to the northern states of the US (hence all the Swedish immigration to Minnesota and Illinois in the 19th Century) In winter time from december to March it can be temperatures down to -20. Mostly though it is grey and damp outside with temp +5 to -5 that time of the year. I have a cabin out in the woods and investigate and alternative and passive way to heat it. The climate is what makes me somewhat sceptical to this solution for myself. Besides that it is brilliant.

@plinble

25 күн бұрын

Wood chip composting? Depends if you can get free green waste. Background heat, at least.

@texasprepperprojects

25 күн бұрын

Thermal mass. Rocket stove

PV dump sand battery is also my current obsession. Debating whether to DC dump from the full array (175 VDC 34 A), take it from the 48V battery bank, or run it through my single-phase 120 VAC service. I've been considering pros and cons of each and keep coming back to 120 VAC as the most practical, in spite of the wear and tear on the inverter, etc. Would love to see more examples from the community here.

@texasprepperprojects

2 ай бұрын

I would do direct DC if you can get the resistance to work out

looks like you can add more sand to the pot... i would keep the wires at the bottom and run up inside walls .. can put inside metal garbage can with even more sand .👍👍 or use as a middle of day batteries full dump load . a insulated box over it that can be removed would save heat for later.

@texasprepperprojects

Ай бұрын

Could

Love it brotha thank you for the update but believe it or not i do heat my house with sand in mass so we get very cold i see your points and i agree i have alot more solar then you have available along with the cost is alot higher then you spent but with higher capacity of weight comes more capacity to hold the pipes at 230degrees i really woukd love to send you out our sand battery to test and pick apart i could even come down with my campers sand battery and show you also im retired and my business partner does awesome so i could take the time away i have many friends in texas

@texasprepperprojects

6 ай бұрын

Thanks!

@texasprepperprojects

6 ай бұрын

@@rickdavis9246 What would you like to know?

@jmanchild

6 ай бұрын

Its a basic question he really was pretty deep with his answer i mean honestly hes still bias about sand batterys but its understandable in small scale there not really working because no one runs exhaust pipe threw it and noone is heating it with enough solar to heat it up to over 400c so no one actually has good data to show but they do work i heat my house with it and this guy is correct about alot of things minus running enough solar and sand content weight wise

Will this keep warm overnight? I’m setting up a small green house now. I’m so glad there’s a safer way to heat it during freeze warnings. I was apprehensive about other forms of heating. Thanks so much❤

@texasprepperprojects

5 ай бұрын

in my experience it's about 4 to 5 hours, but it depends on how much heat you put into it!

Supporting heat for water tank? Like inline between woodburner and water tank? Thinking of a sand battery with insulation that goes along a suitable pipe

@texasprepperprojects

Ай бұрын

It all depends on what your end goal is. If it is hot water there are better ways to do it

Well Clark course I picked the cloudiest day so far this month to try and build this thing so I have it all hooked up but we’re not producing anything so I’m not gonna know if it’s working until we get some sun. Can you wire directly from the solar panel right to that heating element?

@texasprepperprojects

4 ай бұрын

That is what I did. 2 panels in series to the element

Thanks, great information! Can you elaborate on how to choose the right heater, what parameters to look for? Looking at some heaters online they say don't use them without water... would any heater work with ac/dc or it has to be specific one, thanks in advance

@texasprepperprojects

Ай бұрын

That's hard to say. It is true that you need to have the heater in something when you turn it in. You really need to follow my math. Figure out how you are going to power it and work your way backwards. A 12v DC heater works, but they are designed to work on 12v.... so if you have a 37v panel from craigslist, you're not getting the best power out of it.

I'm looking for a greenhouse solution. Just to keep things from freezing. I wonder if adding some solid stones, like a dense, smooth river rock mixed into the sand would help with the duration of the heat output. I'm in southern Arizona and right now the morning lows are hitting freezing and just below. The temp really drops quickly just before sun is up so stretching the time the heat is dissipated might be helpful. Thinking of building two units. One with the dense stones, the other without and experiment.

@texasprepperprojects

5 ай бұрын

Nope. Sand or water.

Nice, not just what you're doing, but how to work out what's best for your needs. I'm still trying to work through heat collection from solar ponds. You can get the surface area up at low marginal cost, but need mirrors in winter to bounce any low sun back on. Solar PV is much easier than all that wet stuff, plus there's no lost inertia with the heat batteries. Why ponds? e.g. pond liner, polycarbonate twin-wall cover, and mylar reflector. By the time you have increased the surface area with traditional "wet thermal" using copper pipes/ vacuum tubes etc, you might just as well use solar PV.

@texasprepperprojects

25 күн бұрын

Direct solar water heating using thermal tubes is a lot easier. The only power you need is a Tiny pump. Check out my shorts videos on this

Well done, in particular I liked the lightning question round. Why necessarily couldn't you upscale this? 1 kilowatt to kilowatt worth of solar panels feeding into multiple elements of sand or some other median in a 55 gallon or larger container. Thinking wood stove replacement

@texasprepperprojects

4 ай бұрын

You could. This is what they do in Europe. But I still don't think you can get it big enough to be practical enough for a house. I mean, I think for a 1,000sqft cabin you would need several tons of sand and thousands of watts of solar. In Europe they use geothermal heat for the sand. I just don't think that it scales up well without another heat source

Hello from Reggio Emilia italy🇮🇹

@texasprepperprojects

Ай бұрын

Hi!

Bit concerned with the cardboard cover, there comes a point when the energy in matches the energy going out, hopefully before the temperature destoys the kit. Can't rely on active thermostats to stop your house burning down, needs inherent safety, which you're getting by not too much power for the pot.

@texasprepperprojects

25 күн бұрын

Thanks

Would this work for a non insulated crawl space with a stove fan, just to keep pipes from freezing during the night

@texasprepperprojects

6 ай бұрын

Probably not. You are better off with electrical heating tape pipe wrap and insulation

Would this work for a pool heater? Im picturing using solar panels as picnic tables with the sand battery hold it in place with these tables around the pool heater

@texasprepperprojects

2 ай бұрын

there is a much better way to heat water thank this that is a LOT cheaper. Check this out instead. kzread.info/dash/bejne/p5Z9zaejnqXfoqQ.html

Been thinking to do this with a storage heater, which here in UK is a electric radiator filled with a kind of bricks.

@texasprepperprojects

26 күн бұрын

you need a LOT of them. For this to work, you need TONS of material. Literal tons.

@CANTON76A

25 күн бұрын

@@texasprepperprojects Not sure what you mean, one of these storage heater as big as a standard radiator can store enough energy to confortably heat a room for a full day. They use about 2.5KW .

New to all this heehee. How do you connect the heater to the panel?

@texasprepperprojects

2 ай бұрын

Just wires

That’s neat I didn’t know that could be done now why hasn’t anyone improved on it I’m tech savvy and I’m old so my point is some could make lots of money off a good idea it work so well here to much rain and over cast but love your presentation.

@texasprepperprojects

2 ай бұрын

Thanks !

@hughmarcus1

Ай бұрын

There’s a sand battery heating a full leisure centre in Finland in winter

@texasprepperprojects

Ай бұрын

@@hughmarcus1 yup and its geothermal powered. great idea

good idea . but would Magnifying glass pointing on the pot not produce more heat and if that pot surrounded with volcanic rocks make a better heat generating divice? we know magnifying glasses can set fire to wood ??? but applied to a pot filled with sand could be a safer bet of generating more heat from that pot?

@texasprepperprojects

2 ай бұрын

The problem with something like that is you have to re aim it every 15 minutes as the sun moves

Xcellent video :) I read below some discussion about the wattage of the solar panels themselves, and you stressed the point about the Voltage. Still, can the relationship between the Wattage of the Panel be correlated with the heating response of the element. I assume it can, and I assume it is related to both voltage and the Current that reaches the heating element. Can anyone here help me understand this relationship better ? Thanks.

@texasprepperprojects

5 ай бұрын

Watts = amps x Volts. Also look at ohms law

This sand bank is kinda cool in a minimalistic way. Personally I would throw another $1250 at the system and get one of those DIY 12,000 BTU mini-splits with solar inputs and precharged lines that allow installation with a holesaw. No need for a vacuum pump. Unless it is very cold it will put 2-3 times as much heat into a space as resistance heating would and it's a solar powered air conditioner come summer with a seer of 22. It maybe the quickest ROI of any solar system. It can be hooked to the grid as well so even if the sun isn't quite enough it will draw the extra needed from the grid (or battery inverter) and for use at night. 2 grand and it starts making heat and AC at high efficiency and free when the sun shines.

@texasprepperprojects

6 ай бұрын

They are really neat for sure, but as you said, another $1,000 or more dollars...

@ghz24

6 ай бұрын

@@texasprepperprojects In texas that $1000 or 2 if you needed everything would quickly pay for itself. Not as quick as a water heater element and a bucket of sand does but I'd bet a small fraction of a full system would take. I would think 2-3 years is not an overly optimistic guess. I don't know your rates but I remember your weather. The best feature in my case would be not lugging my window unit in and out every 6 months.

@scottjoyce85

6 ай бұрын

Totally agree. 240 watts is basically the same as 3 candles so for a little more money you could make something actually useful or for the cost of sand, solar panels and a pot you could have the heating ability of 3 candles.

@jasonbroom7147

2 ай бұрын

@@scottjoyce85 - What you may not be visualizing is how easily this concept scales, compared to candles. If you want 2400 watts of heating capacity, you increase the number of panels, use them to heat more sand, and don't have 30 candles constantly burning down to nothing.

@scottjoyce85

2 ай бұрын

@jasonbroom7147 well obviously. But that's not what this video is. And it's still kinda silly to buy a solar array capable of 2400 watts and just heating sand. Never have an efficiency over 95%. If you have 2500 watts of solar then maybe a heat pump makes more sense and then we're talking like 300-500% efficient.... you also need to visualize that if you scale up the solar then you probably have to scale up the sand battery size..... won't be very portable for very long.

think it would work in a 10ftx20ftx7ft tall insulated space? in the winter the space is in the low 40's

@texasprepperprojects

Ай бұрын

No way

Cool

@texasprepperprojects

2 ай бұрын

Thanks

Green house is mostly made of glass so it will capture all 1000W of sun irradiance per meter squared instead of just few% of it limited by area of solar pannels and their 20% of efficiency. But capturing little extra in the bucket never hurts for a slow release over night.

@texasprepperprojects

18 күн бұрын

Thanks

if youre running a grid tied system, you could have a larger version of this in your basement to dump excess energy into when the meter is zero'd

@texasprepperprojects

2 ай бұрын

agreed!

Could it be converted into a smaller version with less panels for a small van?

@texasprepperprojects

Ай бұрын

You won't get as much heat out so it's not worth it. For a fan I would just use an electric blanket. Mine draws 100 watts

whats the max temp of the element? does it burn out/break at some point? i bought a 550watt 120v charcoal lighter, along with many other resistave heating elements to start testing with. a couple of years ago i filled a 40 gallon trash can with sand, ran a copper coil pipe in the sand. planned on pumping water through this pipe down into the sane and the back up to a small heat exchange with a fan on the back side to help heat the house. its all still sitting here, but i have not done it yet and this was going to help me observe how this was going to work then scale up from there. batteries are expensive, but solar panels and sand is cheap, same with copper tubing and other misc things. water has a much high energy density, but it can only go to about 200f before it starts to steam then boil at 212f, but sand temps can climb much higher. i still need to figure out the amount of sand and the temp of the sane needed to heat the house for say 3 days in the coldest of cold winter days, it may end up being way more than what i am hoping for then in the summer maybe continue to cool zones with heat pumps.

@texasprepperprojects

Ай бұрын

it does. this is an ongoing issue i'm having with the sand battery actually. It ends up melting and coming apart. The heat exchanger thing is actually a waste of time. heat is heat is heat is heat. Copper tubes and fans don't make the heat any hotter. Just put the can of sand INSIDE the house and heat it up. Running it through air may make it heat FASTER but doesn't make it heat any BETTER / MORE. To heat an entire house? you will need literally TONS of sand sitting on top of a volcano. At best, you may be able to warm a ROOM.

@jasonbrown467

Ай бұрын

i dont think you understand why i want to use a heat exchange. i am not wasting time on this. i plan on using the sand to store the thermal energy from solar during the day, then use water, pipes and heat exchange to pull the heat out as a source of heat for my basement. i understand how this stuff works more than you assume

@texasprepperprojects

Ай бұрын

Cool

Is there a better way of connecting the heating element with the sand? Maybe weld stainless steel fins to it? Just wondering as the device is normally supposed to be surrounded by water, if its surrounded by air and sand, perhaps its going to overheat? I was thinking additional fins would provide more surface area

@texasprepperprojects

4 ай бұрын

I don't think it matters. Heat is heat is heat

@pfwag

3 ай бұрын

yes, but a water tank heating element is designed to be in water, not sand, and the water never gets above 212F. The sand around the heating element will get much hotter, as the sand is no where near as effective as transferring the heat out and the element will now get even hotter, past what it was designed for.

question when the temp reaches element limit does the element shut off? and then what happens to the energy from the panels?

@texasprepperprojects

5 ай бұрын

It never shuts off

How can you calculate how much sand to use? I am thinking about doing something like having say 200 pounds of sand maybe in a basement, the two panels heat that up and you let the heat leach out all night, maybe it heats the first floor floors of a small house and that has somewhat of a radiant effect. As you say this isn't going to heat your whole house with two little panels but with longer wire runs and the sunshine being free it might still be nice if it just took some of the edge off by acting as radiants floor heat on the first floor. Since this is just a bit of low budget boost and it's really "set it and forget it" that might be an interesting application. This would be good too if your basement had no insulation in the ceiling.

@texasprepperprojects

Ай бұрын

I think that heating a barrel of water with direct solar tube probably would make more sense.

How long does it take to get to room temp? Was thinking it could be used to heat a tent or camper van at night. I don’t like the idea of the small diesel heaters that people use. Great job!

@texasprepperprojects

Ай бұрын

it depends. check out the other videos for data. It really depends on how cold it is outside.

2 questions. Can you use wind turbines instead of solar panels And instead of sand container. Can it be hooked directly to an electric water heater's element where we can pump water to a radiator system?

@texasprepperprojects

Ай бұрын

Yes. Any electricity works. 2, yes... but I think direct solar water heating with black tubing is easier and more efficient

I think I will try this in my chicken coops around the nest boxes, so the eggs are less likely to freeze. An insulated vent and tiny fan to the nest box bottoms. Great work, thanks. I'm still figuring out the whole electrical thing, it's always been hard for me to understand for some reason. I have some spare 380-watt panels I can use. I hope that is not too much for the element.

@texasprepperprojects

6 ай бұрын

What is the voltage of the panel? That's the key thing to making this work well. You're probably better off using an electric dog bed or blanket for that purpose

@scottc8152

6 ай бұрын

@@texasprepperprojects VOC is 47.8. Would that water heater element work good for this panel? I could use more than 1.

@texasprepperprojects

6 ай бұрын

@@scottc8152 What's the rated current for the panel?

@scottc8152

6 ай бұрын

@@texasprepperprojects It is the Hyundai 380-watt panel, Model Number HiA-S380HI STC Rating 380.0 Watts PTC Rating TBA Open Circuit Voltage (Voc) 47.80 Volts Short Circuit Current (Isc) 10.01 Amps

@texasprepperprojects

6 ай бұрын

should work@@scottc8152

Was just looking at ice cube makers, another way to store the solar energy. More of a challenge for a direct hook up. I don't know any more, except Texas shouldn't be needing space heating all year.

@texasprepperprojects

25 күн бұрын

I looked into that as well as chest freezers running on solar. It's just really hard to cheat thermodynamics.

have you seen the 1/4'' x 1'' 40w 12v heaters for 3d printer 'hot ends'? i bought 10 and strapped them to my 10gl water bucket as a solar dump. they can get to 500f!

@texasprepperprojects

6 ай бұрын

Well thats 400w so it doesn't surprise me!

@lezbriddon

6 ай бұрын

@@texasprepperprojects yeah but the other thing is they don't cost much, it's a nice way to heat things from 12v without conversion losses. I do also have a 240v element and a diesel water heater on a loop with the engine so i can even reclaim engine heat losses. (My build is in a camper) but I'm looking at ways to heat the living space as... well... winter...

@texasprepperprojects

6 ай бұрын

nice@@lezbriddon

could this be done with a wind turbine where you have plenty of wind and little sun, and what would change, if anything?

@texasprepperprojects

4 ай бұрын

In theory yes but wind is very picky and harder to do than solar for various reasons

It would be cool to do a DIY heated green house that charges batteries in the daytime and uses the batteries at night to heat, and maybe when there's a lack of power then draw from the grid.

@texasprepperprojects

2 ай бұрын

Just wait more to come on that

How many Cubic Decimeter or Liter was the sand? In theory you can store 0,3Wh in 1dm3/K, hence if I have 1000l, with 120degC and want to take out energy until I have 30degC, I got 27kWh minus some losses. However, Heating up require a lot of more energy, which mostly depend on the insulation. Note: I need around 36kWh of energy (Underfloor Heating System, 34sqm), to heat my house in the Winter at -20degC outside temperature. I am Off-the-Grid in Estonia and I am ongoing testing a bigger thing with around 10m3, a Fronius Primo 4.6-1, a Fronius Ohmpilot with a 3kW Heating element. The rest of the Energy is used by my Victron MultiPlus-II 24/5000 for the rest of my property. Have fun P.S.: My next project for next year is around 600m3 under my Winter-Greenhouse, where the sand will be heated up to 60degC using a Fronius Symo 10kW, Fronius OhmPilot 9kW and an In-Flow Heater.

@texasprepperprojects

29 күн бұрын

Awesome!

You have a metal pot with hot sand inside, it appears not to be thermally insulated so a great deal of the electricity from solar panels is heating the air. Now that you have this heat in the sand what do you plan on doing with it?

@texasprepperprojects

Ай бұрын

The pot doesn't need to be insulated if it is Inside the airspace you are trying to heat. This is a demonstration video not a live setup

I've read mixed reports of wiring panels direct to an element can cause the panels to wear out quicker. Anyone have more insight into this?

@texasprepperprojects

Ай бұрын

I don't know how it's possible to 'wear out a panel' other than if the resistance was too low and the panels were trying to put out more power than they can. Thats why the math is so important, to match the resistance of the load to the panels output voltage and current limits. I'm at about half the limit of what my panels can do

I suspect you already covered this in another comment so sorry if thats the case but... I hear your argument around no need for conductive materials associated with the heating element... heat is heat... But I wonder if you'd get better distribution into the sand with a simple metal connection between the heating element and sand... More importantly, I wonder how quickly the heating element will burn out if it is not having the heat drawn away from itself as readily as it would in a liquid situation. The sand spreads the heat out I'm sure but SO SO much slower than a fluid that can circulate. Have you seen it overheat or blow out with this setup? Maybe it's truly a non-issue, but it would be a concern for me I think...

@texasprepperprojects

4 ай бұрын

Funny you mentioned that. When I took this version apart last weekend the element had been destroyed

@pfwag

3 ай бұрын

Water efficiently draws the heat out of the heating element and sand doesn't. Additionally water won't go above 212F while the sand does, as you measured. The higher operating temp burned out the heating element. You could find a high temp heating element but they would probably be expensive.

@texasprepperprojects

3 ай бұрын

agreed@@pfwag

@niagaraadventure4705

3 ай бұрын

How long had you been running this before it melted?​@@texasprepperprojects

You should try oil. This would heat your house scaled out. You can use oil and start circulation at night through radiators. Burry it underground insulated and done.

@texasprepperprojects

4 ай бұрын

I can't do that at my house but I love the idea of radiant floors

Could you store the heated sand in a bathtub instead? because that sounds super comfy to lie down and rest on lol

@texasprepperprojects

Ай бұрын

you could

All you have to do is get a 1" NPT/US pipe coupling to use as a nut. OD of threads 1.315".

@texasprepperprojects

6 ай бұрын

Thanks! I still don't want to ruin the pot lol

i often think about trying a passive system using the sun, a powerfull magnefying glass, an enclosed stoking area could be for example a pit isloated with sand and earth but the top is a thick glass where a maynifying glass heats volcanic rocks filling that pit or lets say a old 5sq feet freezer. to see how hot it can get. volcanic rock absorbs heat a lot. connected to that old freezer a fan pushing the heat into the home with isolated pipes. I winder if that could heat a home in case of electrical shortage? Or even if no electric shortage those volcanic rocks could be heated with a 3000watts water heater element from the electrical grid. Does anyone think something like that would work?

@texasprepperprojects

6 ай бұрын

Nope. Not to heat a house. But look at my other videos for parabolic tests

I know this is from 3 months ago, but could you do a video where you discuss the possibility of scaling this type of solution, along with the logistical challenges that would create? At some point, you're probably further ahead to use the current from a larger PV array to power a decent heat pump. Still, I'm wondering if something like what was demonstrated in this video, built to a 5x or even 10x size, could be housed inside of a thermal mass, creating a solar-electric alternative to a rocket mass heater?

@texasprepperprojects

2 ай бұрын

I actually think that a 'better' option than anything else is to use a small DC pump to circulate water through a solar heater (basically black tubing). The TOTAL amount of money you spend on equipment and solar vs the amount of BTUs you would get from heating 55 gallons of water or more, I don't think can be beaten. Check out my other videos. I gained 20F in 35 gallons of water with a tiny pump and a pool heater. That's a lot of BTU for the dollar.

@jasonbroom7147

2 ай бұрын

@@texasprepperprojects - There are three reasons I don't like water for storing heat energy - "flash to steam"! Sand can't do that.

@texasprepperprojects

2 ай бұрын

This is true but running water through black tubing isn't going to get it THAT hot

@michellekonzack

29 күн бұрын

@@texasprepperprojects Right, the Black HDPE tubes/pipes start disintegrating above 70degC, hence in a ThermalStorage (Sand or underground) you can not archive more then 50degC otherwise it become soft and deform. Very Bad if you have 300m3 of sand on top. and then a 17x7m winter greenhouse on top. If I heat up the 300m3, I can get only the range from 50degC to30degC out and feed it controlled to the Underfloor Heating System of my house. this is 1800kWh of heat energy which would give me 50 days basic heating if they where no other losses. However, I have to verify the 50degC with the manufacturer of the HDPE pipe, maybe I can get 10 degC more

good explanation of the capability of sand batteries. I think its important to note that while water technically can hold more energy than sand thats only true in practical use while in liquid form. You can dump energy into sand a long time before your sand starts to boil away! I also think that you should explain that 240 watts of power is really only the same heating ability of 3 candles so don't expect amazing results.

@texasprepperprojects

6 ай бұрын

thanks!

Compared to storage in water, DC isn't the best with any water around because of corrosion. A couple of years ago looked at plugging 400W of PV solar straight into my 3kW, 240V immersion heater. Couldn't see anything on the market to do a good conversion. Everything seemed to point to batteries with inverters. An experienced electrical/ electronics engineer could make something which doesn't use big capacitors and lasts. Basically after a DC to AC inverter with automatic voltage control for maximum power. The inverter for my 12V battery tries to keep the voltage steady, but if you draw too much current it trips out.

@texasprepperprojects

25 күн бұрын

You don't need to do inverters for heating elements. A heater doesn't care if it I'd AC or DC. If you had 120v total of solar (4, 35v panels) you'd be set

A mini Fusion reactor should be available by 2030 probably sold at Home Depot

@texasprepperprojects

2 ай бұрын

i wish. Fusion has been '10 years away' for the last 50 years.

@SchoolforHackers

2 ай бұрын

Mr. Fusion, available on Deloreans, of course!

@texasprepperprojects

2 ай бұрын

@@SchoolforHackers I wish!

You will not get your computed 8Amps in the example since those panels max out at 5-6A. Better to use direct formula to size the element resistance needed R=W/ (I x I) where W is power of pannels and I is panel nominal current 5A usually. 500W/25AA = 20 Ohm optimal. I would put 25 ohms to have it working even at 80 % of irradiance rather that designed for the peak power.

@texasprepperprojects

18 күн бұрын

Thanks

I like the video. The real problem with the video is that you have no landscaping in your backyard!!!

@texasprepperprojects

Ай бұрын

Rental house :/

How long does the battery hold its heat or how fast does it cool?

@texasprepperprojects

5 күн бұрын

Check the other videos in the series

How long does the element last? It has been said that without water the element "burns out" and becomes useless.

@texasprepperprojects

26 күн бұрын

This has also been my experience

How long does it stay warm/ hot for?. I'm still going to make something for my not so winter months and maybe use it to heat some water...warm it up as I don't need hot water even for a shower.

@texasprepperprojects

27 күн бұрын

Use direct solar heating for water

@iwinnimi

26 күн бұрын

​@@texasprepperprojects I have insulation panels and was going to create a very small space with the lid bring about 40 gallons of water... and the air in the void to heat my rv. The water doesn't need to be common household temperature of 120f. Just warmer.

@texasprepperprojects

26 күн бұрын

@@iwinnimi I would use a black swimming pool heater and small pump. you'll get more total heat with less electricity used.

Water can hold more energy at 195F and you can move it around wherever you need to with a small pump, tubing and a heat exchanger. You poured water into the sand for better heat transfer and capacity right?

@texasprepperprojects

6 ай бұрын

Nope. Because then I'd have to waterproof everything

@BasaltGuru

5 ай бұрын

Water boils

@michellekonzack

29 күн бұрын

Right, you can use an IBC with 1000l and heat it up to 60degC. With a temperature difference of 40degC, you have roughly 40kWh of heat energy. If you use a SandStorrage with the same energy. you can heat it up to 100degC and need with a temperature difference of 80degC 1,7m3 of sand I choose 100degC, because then you can put into the sand a stainless steal pipe and run water trough and use the heat as you wish

Question: How long does the heat last once voltage stops? If you had that set up to heat up a greenhouse, how long would it continue to pump heat into the area once the sun goes down?

@texasprepperprojects

2 ай бұрын

Check out the other series of videos where I actually test this out. Short answer, once they stop GETTING heat, they immediately start to LOSE the heat. About 5 hours.

@j.r.576

2 ай бұрын

​@@texasprepperprojectsI assume that statement is based on 50lb volume of sand?

@texasprepperprojects

2 ай бұрын

Yes

@j.r.576

2 ай бұрын

@@texasprepperprojects thank you, also for sharing the video. Great stuff!

@texasprepperprojects

2 ай бұрын

Thanks!

Do you think there is any chance this could be used in a van life setup? Considering how most van life vans are "relatively small" inside, you'd think it would work pretty well, it would just be a case of how it would all be setup inside.

@texasprepperprojects

4 ай бұрын

Honestly no. I think it will take up too much space and be too heavy. I think that a Mr Buddy heater on propane or an electric blanket on a battery makes more sense for a van

@TheKnightsShield

4 ай бұрын

@@texasprepperprojects Fair enough. Thanks for the reply.

@texasprepperprojects

4 ай бұрын

welcome @@TheKnightsShield

Imagine insulating this bad boy with some aerogel

@texasprepperprojects

2 ай бұрын

Yup!

I wonder how it would go at heating a bedroom .

@texasprepperprojects

2 ай бұрын

Depends on how insulated your room is

Noob question: does effectively shorting the panels cause degredation (like it would if you shorted a battery).

@texasprepperprojects

4 ай бұрын

It can certainly damage them

THought about doing this for my room which has no heater and has large windows so its always a few degrees cooler then then the rest. The idea was to use excess solar to do it but had no idea how long the heat would last and how much sand id need. From my experience sleeping on the beach, sands gets pretty cold quick at night so I didnt bother. Even the hot oil from my radiant heater gets cold in half an hour or so after its turned off. Youd need to cook a giant rock i think for hours to have it provide heat all night, and thats what they did with rocks in fires and put them under their beds back in the days, not surprising some warm sand wont do much. But its better then nothing, especially with excess solar might as well get some heat out of it, espesially to say transfer heat from a part that isnt getting and solar radiant energy, like the side of the houe not facing the sun.

@texasprepperprojects

6 ай бұрын

if the problem is that your windows are single pane, then you're better off insulating them with pink foam and using an electric blanket. This is what we did in our old house during the Texas bizzard

@pedjamilosavljevic6235

5 ай бұрын

texasprepperprojects explained the most crucial thing about your situation. Insulation (preventing heat to escape the room) is the most important thing. However , it can be costly and complicated to do (and you still can use his advice , or put some thick , multi layer fabric curtains for the purpose ). The next thing (and I'm talking in cost effective terms) is to use some kind of termal mass , like sand , or water , or heat bricks. Your oil radiant heater has low heat mass and puts out relatively low temperature , so , if you (for an example) brick it around (leaving one side open , for normal function during the day) , the time of heat radiation will be much prolonged , after you switch it off. Benefits of the sand battery that is displayed in this video are it's low cost , relative mobility and no cost to operate (if we exclude the cost of solar panels). It can be done with any metal container , or even clay pot , though , it can be troublesome to poke holes trough it (big , or small , depending on a need for mobility and the purpose - is it meant for heating room in the house , or permanent installation in the greenhouse , or chicken coop , or shed/workshop/garage...). Sand batteries can accumulate very high temperatures (which makes them better than water) , which can be used for longer periods of time , until all the heat/energy is depleted. If you have solar panels , or wind turbine , you'll easy solve this problem. Otherwise , it is all down to energy cost. Bear in mind , that in this video , solar panels produced about 240 W , but , during (let say) 8 hours , the amount of energy , stored as a heat is nearly 2 KW (1920 W). You'll get the same results , if you plug in the heating element of the same power rating (2 KW) in the wall outlet for an hour. If it has been done indoors , it will (probably) reach even higher temperature (than in the video). The rest is very well explained in the video , except the fact , that one can get low resistance heating elements , which are made for car/RV/camping use and there are , also , ceramic heating elements , that , usually last forever.

Think beyond a greenhouse! This has many commercial, industrial, grid-scale, and even home applications. Anywhere heat is used for any purpose or with more effort and expense anywhere electrical power is needed.

@texasprepperprojects

2 ай бұрын

the problem is scale. In order to heat more than about 100 square feet you have to have a LOT of sand. Like, literal TONS of it.

@oopsagain1surname

2 ай бұрын

@@texasprepperprojects How big is your kitchen oven

@texasprepperprojects

2 ай бұрын

@@oopsagain1surname but if the pot is INSIDE The airspace, then the heat isn't ever 'lost'

Ciao non so se hai già provato, ma se oltre le barre in alluminio aggiungi delle spugne di metallo otterrai una maggiore superficie di scambio aumentando la resa termica. Anche se devo considerare che avrai anche un minore flusso d’ aria. Poi ho notato che non hai considerato di isolare la parte esterna. Un giro di lana di roccia nelle ore serali ti dovrebbe garantire una resa maggiore. Tu giustamente fai notare che questo sistema non può certo scaldare casa, e vero ma tieni in considerazione anche di usare insieme ad un riscaldatore tradizionale pi puoi sensibilmente abbattere i consumi. Ciao e grazie per il tutto tempo che ci hai dedicato.

@texasprepperprojects

Ай бұрын

Thank

👍

@texasprepperprojects

2 ай бұрын

Thanks

So what is your verdict. Does it work as intended?

@texasprepperprojects

Ай бұрын

This does work. You just need to be realistic as to what you are going to use it for

@qvarsell

Ай бұрын

Thank you for your reply@@texasprepperprojects. Would you say it is equivalent to a 60 w heater 24/7 (since it is 240w, and the sun shines at a good angle perhaps 6 hours/day?) in that case 10 of them would equal to 600 w heater 24/7. it wouldn't be enough for heating a room i cold sweden during winter, but with more panels perhaps it would.

@texasprepperprojects

Ай бұрын

@@qvarsell not in sweden! too cold!

I have 2 150 watt panels and a 300 DC water heater element can I do this ???

@texasprepperprojects

Ай бұрын

Yes

@richardcooney7789

Ай бұрын

@@texasprepperprojects Thank you

What about transferring the heat from the solar panel to your sand battery? Heat lowers the efficiency of the solar panels.

@texasprepperprojects

21 күн бұрын

Just pour water on them

@jerrrdy

21 күн бұрын

@@texasprepperprojects I don't know much about the process, but find it really interesting. I guess it seems like an opportunity to pipe any hot water back down to the sand to store extra energy, but I really have no clue lol

@texasprepperprojects

20 күн бұрын

I have seen videos on cooling solar panels. It seems like a lot of work for a 5% power gain. Now that panels are so cheap it's not worth the trouble

What about nicrom wires? Cheap and easy to install

@texasprepperprojects

5 ай бұрын

Heat is heat is heat

@MrMEmEmEmEMEMEeeeeee

2 ай бұрын

​@@texasprepperprojectsThink maybe he's addressing the question of using nichrome wire as the heating element to fix the high temp element burnout issue...

What about vacuum solar tubes ?

@texasprepperprojects

6 ай бұрын

What about them?

@MasterBuilderofTruth

6 ай бұрын

I wonder if more heat could be collected with evacuated solar tubes

@texasprepperprojects

6 ай бұрын

I doubt it. It would depend on surface area of the tube, angle, size, etc. And then you have go be able to efficiently transfer that heat someplace

I wonder what differences you would notice if you used black sand instead of blonde sand. Basically iron vs silica 🤔 Granted not everyone will have easy access to black sand but lots will.

@texasprepperprojects

3 ай бұрын

Interesting question

@Chaphillionaire

3 ай бұрын

@@texasprepperprojects If you do not have access to "black sand", ask a gold prospector 😉 Taking that idea a little further, I wonder what would happen if you made a black sand "core" that contained the heating element and an outer "jacket" of blonde sand as an insulator since the black sand should have drastically different thermal properties.

@pfwag

3 ай бұрын

See my comments above. It's the science of heat storage.

What about the possibility of heating the sand directly with a solar heat collector?

@texasprepperprojects

Ай бұрын

What about it? Are you talking about a fresnel? Check out my other videos for testing

@sansabh

Ай бұрын

​Okay, I will. What I was thinking about is an insulated sand pit with a copper plumbing grid inside and a solar heat collector (double pane with black sheet atop sand, essentially) on top. This just outside the greenhouse. The copper plumbing grid is to feed a larger, cheaper air duct feeding the greenhouse t​@@texasprepperprojects

@texasprepperprojects

Ай бұрын

Leave the sand inside the greenhouse

couldnt you simply wire up pannels directly to an existing hot water tank if you wanted hot water for a shower?

@texasprepperprojects

5 ай бұрын

you could, but it's not going to get very hot very fast unless you have 120 volts of solar. If you want hot water, there are much better ways to do that.

For energy storage of this kind, the higher the temp delta, the better the results. heating sand above 500 has more density than water sub 212

@texasprepperprojects

2 ай бұрын

50F to 250F is a hell of a delta

Add 100'+ coil of copper tubing. You have a pool heater. That's what I am doing!

@texasprepperprojects

2 ай бұрын

Just use a normal pool heater and a tiny 12v pump. Much cheaper and less losses kzread.info/dash/bejne/p5Z9zaejnqXfoqQ.htmlsi=HicfD0-KX4787e1u

This is fantastic. So is the idea that you are running the heating element at about 25% of its potential because it's a resistive element?

@texasprepperprojects

2 ай бұрын

I'm running at 25% because that's as many panels as I have to put out the right wattage. If I had 4 panels I could get to 1kw

Aside from safety, any reason why this wouldn't be a good way to heat a van?

@texasprepperprojects

Ай бұрын

Nope. I don't see why not. Just keep the sand inside the van and run the solar wires inside

@plantstho6599

Ай бұрын

@@texasprepperprojects would need to calibrate a thermostat so I could leave it on while at work. Currently in Southern US and was thinking of moving to MN. Wouldn't survive the winter without heat and this seems like it would be cheaper and more reliable than a Chinese diesel heater.

@texasprepperprojects

Ай бұрын

I don't think you are going to be able to do a thermostat. At best just plug it in and cross your fingers. The greater issue is that Minnesota in winter only gets about 2 to 3 hours of peak solar sunlight so you'll have to have a lot of panels for this to work. I think you are better off with a diesel heater or buddy propane heater actually for your situation

@plantstho6599

Ай бұрын

@@texasprepperprojects valid point. I have 900W of solar and the potential for 30A of alternator charging. That still may not be enough. Should add some wind, since I've practically maxed everything else out. At any rate, would probably run the element off my 120v inverter since it's already on for my fridge.

@texasprepperprojects

Ай бұрын

Sounds like you have enough power. The setup is pretty cheap so give it a try!