Great video and nice background. I must say you're the only person I trust I'm regards to giving honest review of a heat pump vs gas boiler costs.

@TimAndKatsGreenWalk

Жыл бұрын

I think too much is made of how heat pumps will save on your energy bills when that isn't really true in any meaningful way. Having said that, now that I have solar PV and home storage batteries installed I am able to make a heat pump cost a lot less to run than a gas boiler. But that needs a large amount of up-front investment which then takes longer to recoup (I reckon about 12 years for the whole combined system of solar, batteries, and heat pump).

I do have a combi boiler, no intention to alter my system, but admire what you are doing. Keep up the great interesting videos.

@TimAndKatsGreenWalk

Жыл бұрын

Thank you!

Hi. I’m a gas engineer and there’s a couple of points I’d like to make. Firstly if you live in a hard water area then heating your water with immersions will cause them to scale up very quickly. You are always better off using the indirect coil that’s fed from the boiler as any saving you think you made will quickly be eaten up replacing knackered immersion heaters. Secondly you’ve based your calculations on a yearly amount but for probably six months of the year you’d be heating up the boiler and pipework to run the heating anyway, so drawing off 4kwh or so for dhw is neither here nor there as once the trvs on the system shut down almost all boilers will have spare capacity to heat up the cylinder. So I’d say that so long as you don’t live in a hard water area or you have a softened supply and you have a time of use tariff and that you only do it in the summer it might be worth it. For everyone else. Don’t bother. Once you scale up the immersion elements they get less and less efficient and you’ll soon be using a lot more than 5 kWh to heat your water.

@TimAndKatsGreenWalk

Жыл бұрын

These are all good points. I'm planning on doing a follow-up video (hopefully next week) so will raise these points in that. Thanks for brining them to my attention.

@danielspillett5393

Жыл бұрын

Even now over the last winter I was only using £30 a month in my gas boiler and now the it's warmer I'm using probably 10 to £15 a month maximum because I only use the hot water for a shower and for washing up and it will cost me a fortune to heat up a when electric is 3 times the money that has is gas give you hot water every time you turn the tap on immersion heaters have to be heated for a large cost has been working class I could not afford to keep an immersion heater on 24/7 it would break me

Great video . Keep up the good work

@TimAndKatsGreenWalk

9 ай бұрын

Thank you.

Thanks for this. I’m trying to figure this out for my oil boiler but it’s hard to tell how much I’m using on heat tank as there’s not really much data to go from!

Im on a similar journey of spreadsheets and notes and such, so really enjoying your videos! I have a combi boiler, but I have had a tank installed and now it's just a system boiler. Sound crazy? No. It's part of the plan to get off gas, but also the pipework in my house is such that it always takes so long for the hot water to get to the taps that it was costing me 8-12kwh of gas on water daily. seems like it'd all have to get redone to fix it which would cost more than the tank did. With octopus go (and later, solar diverter), I'm now using 6kwh total almost all from overnight and about 0.3 kWh at day rates maintaining the top temperature. Water takes just as long to get to the taps, but it's about the same actual cost and not wasting gas *or* as much water. At this rate it'll take years and years to pay for itself - but it *would* eventually - but once the solar diverter is in it'll pay for itself in about a year at current rate of price increases. Plus now I'm ready to be able to switch to some form of electric heating for the house, be it wet or dry, without worrying about where my hot water will come from. The point is: combi boilers can work here, you just have to give up the "instant" hot water aspect. Also can highly recommend the mixergy tank if you're starting from scratch. It lets me set a heating source for certain periods as well as a schedule to fill the tank back up, so I until I get the solar diverter to keep it topped up I can set it to use gas after dark in case someone suddenly wants a bath, and electricity the rest of the time, including its Octopus go period for a full charge. I'd like it to give me more granularity really but I guess that's likely to come with software updates. ^^note, I am not saying what I've done here is in reach of everyone, and I'm not meaning to brag. I have a small but high energy use house, and I was *super* fortunate to have found myself in a position to make these investments the year before things went nuts, but only after years of saving and I've had to do it all with no grants due to idiot govt switching focus purely to heat pumps *just* before that. It's the best decision I ever made, mind you, and it's set me up to be able to then get the new tank this year, again just in time for those marginal cost savings to add up. Lucky. Very lucky. But Many people don't live in suitable places even if they had the money to do it, which they don't. And my heart goes out to them. Govt should be funding "electric ready" which would mean anything that would get your property prepared to switch off gas: insulation, solar, batteries, hot water tanks. If it'll fit in your house and you want it there should be a govt contribution. Far happier my taxes going on that for people, with a corporate windfall tax to cover freezing energy costs for a bit. ...political. sorry. Didn't mean to. I'm just really worried about my friends and neighbours who absolutely can *not* afford to do this stuff without help, and stupid mad at the government royally screwing up any level of transition plan. It's all magic bullet or nothing to them.

@TimAndKatsGreenWalk

Жыл бұрын

That sounds great. I'm hoping getting solar panels plus solar diverter will get us one step closer to getting rid of gas.

@jezlawrence720

Жыл бұрын

@@TimAndKatsGreenWalk *if* the diverters work as advertised it totally will. I only have like a 3.2 kw solar rig, so in winter that's operating more at about 1.2. ...I still exported a kWh or so on more than half the days last December (note I have a 8kwh home battery also as part of solar install. This is why I still have a surplus in December, because it also tends to be charged to full overnight and only topped up a bit via solar, whereas summer I don't even bother charging the battery and export an insane amount really - I was a net negative user over the course of the year on electricity, by a little bit. That little bit can hopefully now go to my water. Electric heating will put me back to net import, which is why it's last. I *need* all this stuff before electric heating is remotely feasible). That's enough to keep the tank at temperature or even slightly topped up *most* days provided I charge to full on octopus go overnight. Earliest delivery out installer can get for us is November. Race you! Whoever gets one first report back here on performance lol

@TimAndKatsGreenWalk

Жыл бұрын

@@jezlawrence720 haha! Yeah, I've had my system on order for a while (solar, battery, Eddi) but it's just taking ages. The installers are all so slammed right now (which is encouraging, actually). Looking forward to doing videos about it all in due course.

We've just switched over to the British Gas electric driver tariff which is cheaper overnight (as we have electric / hybrid cars) so I'm going to try using the immersion heater on a timer or maybe a Hive plug for a while. Our water is medium hardness apparently so it will be interesting to see how long the element lasts!

@TimAndKatsGreenWalk

Жыл бұрын

I hope it works well for you. Worth an experiment at least.

I have a pulse counter on my gas meter and current clamp on my immersion feed all datalogged. Tank is 250L unvented with dual 3kw elements (controlled with dedicated contactors). It uses around 7.5kWh to heat the tank to about 57’c which on go costs about 55-60p a night. Doing the same on gas uses about 11-12kWh and costs about 95p at the same octopus 7.5p gas rate you mentioned. So using far more gas to heat the same amount of water and nowhere near the 90% efficiency. My tank is in the loft and the boiler in the garage - so I think i’m loosing some heat on the journey. High or low flow temperature doesn’t make any appreciable difference. (flow and return temps also datogged)

@TimAndKatsGreenWalk

Жыл бұрын

Yeah, gas is definitely less efficient than electricity due to the sort of losses you mentioned. I'm trying to make my gas system as efficient as possible but I don't think I'll ever get to 90%. In the video I use 6 kWh for gas vs 5 for electric, which is an assumed efficiency for the gas system of 83%, which I think might just about be achievable. I should have another video out in a few weeks with the results of my recent experiments to achieve that. Although in the long run I'll be using the immersion heater powered by excess solar (in summer) or overnight power (in winter), so I'm mostly doing these experiments for my own curiosity in the mean time.

Great Video so i must share my attempts to control this. I bought a Tesla T Smart thermostat with smart phone app.. It takes 1 hour to heat my tank up to 65Deg. so between 4 & 5am I super heat water to 65.. then all day the gas therm is set to 50. My night rate is 4.5p.. I charge my car, i use the dish washer after midnight too.. It can take quiet a long time for the water temp to drop from 65 to 50. thus keeping gas usage to a min….

@TimAndKatsGreenWalk

Жыл бұрын

Very nice. Thanks for sharing your setup!

I got my 4kW solar panel system back in 2013 and get around £800 a year for generation (south facing panels) which is 25p per kWh off the governement. On a sunny day and while the fridge etc wasn't running, I turned the 3kW immersion on and went to check the meters. It was still using the grid as well as solar. I was offered a device like you mentiined for an extra £450 but didn't bother as it would eat into profits. The panels cost £5000 so paid for themselves in around 6 years. Total energy bills for a 5 bed house pre the deliberate energy price hikes was £750.

@TimAndKatsGreenWalk

Жыл бұрын

Unfortunately we've missed the opportunity to get a feed-in tariff so when we get solar panels using excess to heat the water will be well worth while. I'm glad yours have paid for themselves already.

@roberthuntley1090

Жыл бұрын

My experience is that its worth getting a solar PV diverter as it gives me free hot water for about 80% of the year (on really cloudy days there isn't any spare power). Mine reports a saving of 5919 kWh since it was installed in 2015. My saving is limited by the amount of hot water I can actually use before the tank thermostat cuts of the heat (I live on my own) so I bought another one (second hand from a seller on Amazon) and connected it to a string of cheap convector heaters totalling 3 kW to supplement the heating system. That one has saved an extra 4600 kWh since it was installed in 2016 (obviously it sees less use because there is no need to heat the house the several months of the year). The only caveat is that I have to manually switch between them and only use one at a time (they would probably interact badly with both grabbing any spare power, forcing power to be imported from the grid to meet the double demand). Electricity price has varied over that period, but my estimated total saving is now approaching £1500. My solar system is only rated at 3.1 kW, so you would have more spare power available than me.

@TimAndKatsGreenWalk

Жыл бұрын

@@roberthuntley1090 very nice. I'm looking forward to getting my system installed. Not much longer to wait, hopefully.

Re your comment about lagging pipes to save gas - you might like to have a look at Heat Geeks here on YT. I also have lagged some of my internal pipes - but discovere today, that it may well have been conter-productive! Some things that seem logical, can sometimes be quite wrong! Worth listening to Adam at Heat Geeks, as he really knows his stuff!!

@TimAndKatsGreenWalk

Жыл бұрын

I watch Heat Geek too. Their point about not lagging internal pipes was for the central heating not the hot water. I'm suggesting lagging hot water pipes, which will definitely be beneficial.

Same idea as Economy 7 from years ago (it was 7 hours lower rate then) most suppliers have scrapped these cheaper night rates, wonder why? The lower element on the cylinder was attached to the timer and the upper element was the boost that only heats the top of the tank.

@TimAndKatsGreenWalk

Жыл бұрын

Indeed, although these are now done using the smart meter half hourly data rather than having two separate meters. You should find most suppliers offer time-of-day tariffs nowadays, but sometimes you have to dig around on their websites to find them.

Great video, you can now buy a Tesla -T-Smart, this device is a wireless immersion heater. I've just bought mine to take advantage of my excess energy from our solar panels.

@TimAndKatsGreenWalk

Жыл бұрын

Yes, indeed, we'll be getting the MyEnergi Eddi to do a similar thing. Diverting excess solar for hot water is such a great idea.

@BOB57ER

Жыл бұрын

@@TimAndKatsGreenWalk I looked at MyEddi, it's a far superior device, however at a higher price. £80 vs. £800.

As a gas engineer I'm currently monitoring the hot water usage of a number my customers with different heat sources and storage solutions. Will factor in your results as part of the process.

@TimAndKatsGreenWalk

Жыл бұрын

That's great, I'm glad this was helpful. I always approve of gathering reliable data to help inform decisions.

Batteries of decent capacity definitely the way forward to make use of the off peak tariffs Will pay for themselves within a few years.

@TimAndKatsGreenWalk

Жыл бұрын

Yup, we'll be getting a good sized battery installed along with our solar panels for this very reason.

@edwardpickering9006

Жыл бұрын

@@TimAndKatsGreenWalk Just be careful you don't buy too big a battery if you don't know what your excess solar generation is. Start with a small one and add more capacity if you need it.

@TimAndKatsGreenWalk

Жыл бұрын

@@edwardpickering9006 I've done quite a lot of calculations for our future requirements with the aim of electrifying our heating as well as the hot water, so that'll require quite a hefty system. But yes, I agree, you shouldn't make decisions without either experience or calculations.

Hi I have a combo boiler and big white immersion tank . My tank is switched off . And my combi boiler is always used for how water & heat . Do I need to put it on or shall I just leave it switched off unless my boiler packs in

@TimAndKatsGreenWalk

9 ай бұрын

If you use your boiler for your hot water I suggest continuing to do so, unless you have a time of use tariff with super cheap overnight electricity.

Im looking to change the digital time switch to a wifi enabled time switch. I have a Boiler that is For heating only - it heats a Tenenmant Building. Right now we use the Drayton Time Switch Lp722 7-day Programmer, which every week we have to go manually and adjust depending on the weather or if the building is occupied. I'm Looking to replace this with something that i can control with my phone through WIFI - So if I need to put the heating on or off or set times I can do this from wherever I am. We don't require a thermostat as this building is old and draughty and we have several floors and many rooms (B and B). question is do I need and electrician or plumber? and where can i find a new switch?

@TimAndKatsGreenWalk

Жыл бұрын

You will probably need an electrician, yes, but shouldn't need a plumber. I use an eddi by myenergi and that does wifi control but it's a bit overkill for a simple timer (it also does solar divert and costs about £400). I don't know of any other wifi enabled immersion timers, I'm afraid, but I expect you could find one with with a Google search.

If immersion heater is on a timer and cuts off at 4.30am, is the water in the cylinder still nice and hot when you need it for morning showers etc?

@TimAndKatsGreenWalk

Жыл бұрын

I should think so, yes. When I was testing the immersion heater I was putting it on at about midday and it was plenty hot enough even the next morning.

We have a 35 year old boiler with a pilot light and that used 4kWh every day no matter what. Turning off the gas and using the immersion on Octopus flux at night worked out at about half the cost. We only need hot water for a morning shower so no need to keep it on all day. We wanted a ASHP but the complexity and cost involved in having it doing DHW with buffer tanks, expansion vessels, diverter valves, new rads, new cylinder etc made it economically ridiculous. (150 year payback) Now that we have DHW covered, we can opt for the simplicity of air to air heat pumps, just like Tim & Kat. Our house is almost PassivHus standard so total install is going to be about £4k. We have very soft water but new immersion elements cost about a tenth of a gas boiler annual service.

@TimAndKatsGreenWalk

Жыл бұрын

Very nice. Sounds like a good setup.

Did you mention that as part of the cheap overnight tariff, the daytime rate was 40p? I still think that timing the heating has more potential for saving. We use most hot water for showers after breakfast, we are retired. So we heat for a limited time, 90 minutes, in the morning all year round and there is still enough hot water for the odd amounts needed later in the day. Also we turn the water heating off if we are away overnight. We use 5kwh per day for gas water heating.

@TimAndKatsGreenWalk

Жыл бұрын

Yes, the GO tariff is currently 7.5p overnight and 40p all other times. For a full cost calculation your daytime electricity use should be considered too. Switching to a time-of-day tariff usually comes with an increase in the day rate, so it might work out more expensive if you use a lot of daytime electricity. But if you use little electricity other than for hot water it could work out better to have a time-of-day tariff like Octopus GO.

Hi can the cylinder be used for central heating too?

@TimAndKatsGreenWalk

Жыл бұрын

No, it's just for hot water.

You also have to factor in the cost of running the electric pump for the boiler as well as all of the boiler electronics (fans etc) whilst it is heating your water.

@TimAndKatsGreenWalk

Жыл бұрын

That is a very small load in relation to the rest of your electricity usage. It will be a tiny fraction of the cost overall.

@maverlk7

Жыл бұрын

I have some sums on this. Assuming 2 hours a day of timed water heating, the pump runs continuously on most systems. The boiler fan, thermostats, zone valves and boiler electronics are also active. Pumps are 60 to 80 watts and flue fans 30 watts. The rest probably under 10 watrs, so a realistic total is 100 watts x 2 hours x 365 days = 73 kw per annum. At 29 pence per kw this is c. £24 a year in additional electricity use on these assumptions. The immersion using octopus go has no ancillary electricity load, so that is my preference for hot water when heating is off. It is an interesting rabbit hole you can get into with all this👍

@TimAndKatsGreenWalk

Жыл бұрын

@@maverlk7 nice calcs. Yeah, I'm aiming to move to using the immersion overnight soon as well, it makes a lot of sense.

I got immersion tank could i heatin my property with immersion water tank+radiator(without boiler)

@TimAndKatsGreenWalk

11 ай бұрын

No, they're totally separate sets of pipes, I'm afraid.

What would you suggest doing to work out exactly how much the immersion heater is currently costing? My parents are paying almost £1000 a month (!!) to Scottish Power, and we can't figure out what is causing these staggering sums but both my parents and SP think it's likely to be the immersion heater. They don't have gas running to the property, and only have the immersion on for about 1.5 hours a day, so I am baffled as to how the costs can be soaring this high. They do have a couple of small space heaters that they turn on occasionally but even those shouldn't be generating costs that high from my calculations :/

@TimAndKatsGreenWalk

Жыл бұрын

Goodness me, that's eye watering. If they have the immersion heater on for 1.5 hrs a day that sounds about right to me, as that's 4.5 kWh, which is similar to what we use. You'd really need to check their usage and tariff from their bills to be sure but at 40 p/kWh that would be £1.80 per day, so about £55 per month for hot water alone (obviously worth checking their actual tariff, I chose 40 p/kWh as a reasonable starting point but there is a big range of tariffs right now). Check their bills and see if their usage is significantly higher than this. We use about 5-6 kWh of electricity for non-hot water related stuff so combined with hot water that would be about 10 kWh per day, which is £4 per day (£120 per month). It could be that SP are factoring in their winter heating usage, so check back to their bills from the coldest months to see if their electricity usage goes up significantly due to heating. Even so, £1000 per month sounds extortionate. Good luck getting to the bottom of this, I wish you and your parents all the best.

@maddiem5921

Жыл бұрын

​@@TimAndKatsGreenWalk thank you so much for replying, I will go through the bills as you suggest and see what I can glean from those. Do you think it would be effective to take meter readings before and after the immersion is switched on to get a picture of how much of the electricity use it's responsible for (they don't have a smart meter and I can't convince them to get one, so just the main meter)?

@TimAndKatsGreenWalk

Жыл бұрын

@@maddiem5921 yes, you could do that. Usually immersion heaters are about 3 kW, so running for 1.5 hrs = 4.5 kWh, assuming the immersion is actually running for that whole time (it might switch itself off early if the water reaches the required temperature). If the numbers you get from reading the meter before and after are significantly different from 4.5 kWh then something funny is going on (e.g. possibly two immersion heaters running at the same time?). It's funny, my in-laws are very resistant to getting a smart meter too. I don't really understand why you'd not want the extra information, but there you go. Best of luck!

How do you calculate gas consumption in KWh while the gas meter shows the m3. I had used 2 m3 in one day, which I converted using formulation which gave me 22 KWh. Based on this I found the gas heating is much expensive.

@TimAndKatsGreenWalk

Жыл бұрын

Our gas bill had the conversion from m3 to kWh, so I just used the values from the bill. I guess it depends on the supplier whether they provide that value or not.

You should check your hot water tank immersion element has a thermostat, otherwise you risk taking the temperature up too high.

@TimAndKatsGreenWalk

Жыл бұрын

Yup, I've found it and tweaked it already! I might cover this in a future video at some point.

if you heat the tank the thermostat will turn off the heat(using electricity),if using in the evening the water would have lost some of it's temperature.when you heat your water you heat in the morning and evening to keep the temperature.(gas).

@TimAndKatsGreenWalk

Жыл бұрын

Heating once a day is totally sufficient, the cylinder is well insulated and keeps the water hot for ages. If we don't heat the hot water a second time it's still plenty hot enough even after 24 hrs.

Seem to be some high figures here. We find for two of us 20 mins a day with gas boiler (in summer and tank is in very warm south facing bedroom so minimal heat loss gives enough for two quick showers or one long one plus any other ancillary hot water usage. Smart meter on Octopus Flexible shoeing 3.19 kWh, 60p. Goes up a bit in winter. (Do smart meter costs factor in standing charge? Not tried electric to compare yet but we do have very hard water so may not bother now. Solar panels next consideration.

@TimAndKatsGreenWalk

Жыл бұрын

I'd suggest watching some of my recent stats videos to see how adding a solar and battery system changes all this.

@dcornwell7130

Жыл бұрын

@@TimAndKatsGreenWalk Thanks for taking the time to reply. I am watching the other videos, all of which are very watchable.

With a cylinder you can heat more water than is required and also quickly run off your cheap heated water the next day; that's why combi's are more efficient.

@TimAndKatsGreenWalk

Жыл бұрын

They both have their pros and cons. Combies are generally more efficient yes, but a cylinder can be heated by solar panels, which can be useful if you have them.

Octopus go is only if you have a Ele car ,so I have to buy one around £20 grand ,to save a bit of gas lol, I have solar system with a combie gas boiler , I’m keeping my gas boiler it’s still cheapest option at mo ,looked at fitting heat air pump but there just to exspensive and they look so ugly ,so I’ll stick to combie for now ,I’ve had my solar for 2 months and already cut my monthly bill by at least half,I’ve got batteries,which work great ,I have 4 ,which can give me 10.4 kw, I’m changing my Ele shower to one runs off the combie ,I’m on flexible octopus at mo ,so just waiting to see what there new prices will be on all there tariffs ,as winter comes and solar is less see what best one to charge battery’s at night ,also gone onto there outgoing tariff that pays me for any thing I send back to the grid once battery’s top up

@TimAndKatsGreenWalk

Жыл бұрын

I guess what I was trying to say in my video but failed is that if you're already on a time-of-day tariff like GO then it's a good option to use your immersion heater overnight rather than using the gas boiler. But yes, if you're not already on a time-of-day tariff it's unlikely to be worth switching. I'm doing a follow-up video shortly to better address this and a few other points people have raised, so watch out for that one. I've got big plans to electrify our heating and getting rid of the gas entirely, so that'll all be covered here too in due course. Part of that involves solar panels and battery storage, plus some form of heat pump eventually, but it'll take a while to get it all installed so it's a several year plan at this stage. That's why I started this channel, really, so I could show folks what I was doing so that it might help others in some way. I'm glad your solar panels and batteries are working well for you so far. I'd recommend switching to GO before October as if you switch now you'll lock in for a year at the current prices of 7.5p overnight, 40p day rate. If you wait until after Oct they'll all jump up a lot. I switched a week ago for this exact reason. They let me switch even though I don't yet have an electric car, I just needed to click a box saying I had one! I asked them about this and they said they're only checking the EV details for a random selection of applicants so you might find you can switch without needing an EV. I think it's stupid they've added this requirement as surely people like you with battery storage should be allowed to use GO, as that's the ideal combination. I hope they'll revert that requirement at some point.

@kevinjackson6387

Жыл бұрын

@@TimAndKatsGreenWalk oh ok I might try go then even though I haven’t got a ev,I thought they asked every one if they had a ev ,they can only say no i surpose

Which option is greener?

@TimAndKatsGreenWalk

Жыл бұрын

Kinda depends when you run the immersion heater. As long as you run the immersion outside of peak time (say 4-6 pm) the immersion is greener by a small margin. Unless you're using your own solar panels to run it in which case it'll be much greener any time you have excess solar power.

How much hot water will you get for 6kwh per night it does not sound like a lot?

@TimAndKatsGreenWalk

9 ай бұрын

That's about 150-200L.

@allanpedley2231

9 ай бұрын

@@TimAndKatsGreenWalk thank you. I had just read before your video that using a 3kw immersion would take 188 minutes though it never specified a temperature. I am on Octopus Agile with an EV so very keen getting off gas enjoyed part 2 as well 👍

Just note that Octopus use UTC not local time

@TimAndKatsGreenWalk

11 ай бұрын

No they don't. See the FAQ on this post: octopus.energy/blog/go-faqs/#:~:text=Octopus%20Go%20is%20an%20electricity,between%2000.30%20and%204.30am).

Cost and maintenance of boiler? £200pa?

@TimAndKatsGreenWalk

Жыл бұрын

Possibly. I've not done the sums on that one. Sounds about right.

Not sure this is very scientific. Your using a period of a day, but don’t measure how much you use. Combined with the fact that your comparing cost in pounds dependent on which provider your with , doesn’t make for a very good comparison. Better way to do it would to use all the hot water in your cylinder until the outlet temp reach the same as the inlet temp. Take a meter reading ( all other appliances would have to be off of course) Then switch on the heat source and see how much it uses to heat the cylinder back to the set temp ( ensuring the immersion and cylinder stat are set to the same) Then repeat the test using the other source, again taking a meter readings before and after. Then do the maths and calculate the energy used. Then knowing this, you can directly compare which is cheaper when using different tariffs etc. but only on your house, with your tariffs. You have way too many variables ( boiler efficiency, system efficiency, immersion efficiency) , involved to answer the title of the post.

@TimAndKatsGreenWalk

Жыл бұрын

Please see my previous video where I show how I calculate our average energy usage for hot water. Average use per day is exactly what's required and my method gives me exactly that. I.e. measuring what actually gets used per day over several days.

@dgilbert222

Жыл бұрын

​@@TimAndKatsGreenWalk I agree with your overall findings but not necessarily the detailed calculations. i.e., you have assumed in both videos a 90% gas efficiency, but there are significant losses in the hot water heating circuit itself. The process by @Jubblies mcsugartits is the way I would have done it as you then measure actual energy usage to heat a tank of water by x degrees from y taking all system losses into account. However, it wont change your findings, just the ball park energy used for each calculation. I do enjoy your videos though so keep up the good work 🙂

@TimAndKatsGreenWalk

Жыл бұрын

@@dgilbert222 thanks. In this video I'm trying to show how you would calculate your own daily costs, based on the energy you use (gas or electric), which I think is a more meaningful value than what it would cost to heat a whole tank. My usage estimates are reasonable as I did daily averages for both the immersion heater use (5 kWh) and gas use (7 kWh measured, but using 6 kWh in these calcs because I believe I can improve the efficiency slightly so this is a reasonable target). I suggest several times that folks need to do their own calculations based on their own usage, as they may have different systems and tariffs, so hopefully people will not just use my figures. It's meant as a demonstration rather than an absolute answer. I hope that makes sense.

I believe Octupus Go is only suppose to be for EV owners only,, so to be on this tariff you have to spend in excess of £20000.

@TimAndKatsGreenWalk

Жыл бұрын

This is true. But if you're already on it then it becomes a valid option. I guess that was what I was trying to say but possibly failed to convey properly in the video.

@nicks4934

Жыл бұрын

£20000??? Or £2000

Why not include thankless instant water heaters?

@TimAndKatsGreenWalk

3 ай бұрын

This video shows what I had access to at the time. I don't have a tankless instant heater so couldn't test it against the two methods I did have access to. Pretty simple, really.

All I know my electric bill is cheaper than gas bill so if I run hot water on it on it instead then I should see overall less cost.

@TimAndKatsGreenWalk

Жыл бұрын

Yeah, it's not as simple as that I'm afraid.

There is no chance of getting those electric prices. Energy companies are not taking new customers.

@TimAndKatsGreenWalk

Жыл бұрын

Indeed. I did say you'd have to do the calculation using your own tariffs.

Only. 4 hours of cheap rate. Be nice if you worked out the typical increase in cost for day rate. Suddenly you may find your not saving anything

@TimAndKatsGreenWalk

Жыл бұрын

Yes true, I only hinted at that in the note I added. This video was focused on hot water only but ideally I should have done the full calculation including all other electricity use. I'll see if I can fit in an extra video to explain that soon.