Domestic Solar PV Quotes 2020

unkel · 16-05-2020 6:03pm

garo wrote: »

True roof slope will be a factor and you may get very little output Nov-Feb compared to a S facing panel. But I just looked up a panel at 30 degree tilt facing NW and it produces 55% of a S facing panel and 70% of a panel facing due E or due W.

If panels would get a good bit cheaper (and we got a FIT), I'd be tempted to plaster my north facing roof with PV as well.

gomamochi1 · 18-05-2020 3:44am

unkel wrote: »

If panels would get a good bit cheaper (and we got a FIT), I'd be tempted to plaster my north facing roof with PV as well.

Is there a website or app that can gauge the best pitch and aspect for northern hemisphere countries like ireland . Also heard on here about vertical mounting panels for eg gable end of garage is south facing would it be worth it along with west garage roof? Thanks

championc · 18-05-2020 9:24am

gomamochi1 wrote: »

Is there a website or app that can gauge the best pitch and aspect for northern hemisphere countries like ireland . Also heard on here about vertical mounting panels for eg gable end of garage is south facing would it be worth it along with west garage roof? Thanks

First of all, to see the sun angle at any time of the day, on any day of the year, use https://www.timeanddate.com/sun/ireland/dublin

So the optimum is to have the sun directly overhead and therefore perfectly perpendicular to your panels. Therefore, vertical panels on a gable end wall facing west will be increasing in output as a setting sun gets lower in the sky, with the angles becoming more and more favourable by the minute

garo · 18-05-2020 10:46am

gomamochi1 wrote: »

Is there a website or app that can gauge the best pitch and aspect for northern hemisphere countries like ireland . Also heard on here about vertical mounting panels for eg gable end of garage is south facing would it be worth it along with west garage roof? Thanks

Google PV-GIS. Ah here: https://ec.europa.eu/jrc/en/pvgis

But remember you are not just trying to maximize total output but output at the times you need electricity. No point having loads of output at noon when no one is in the house and then nothing at 6pm.

gomamochi1 · 18-05-2020 11:26am

garo wrote: »

Google PV-GIS. Ah here: https://ec.europa.eu/jrc/en/pvgis

But remember you are not just trying to maximize total output but output at the times you need electricity. No point having loads of output at noon when no one is in the house and then nothing at 6pm.

Thanks was on that website already though could not make sense of it. I am trying to maximise the solar gain as the system we are getting has 4.8kw pv panels with 4.8kw battery's and hope to charge EV at home some days and run the gaff off the batteries at night and remainder to go into the car at night when things get back to normal we will be doing more miles than we are presently just in out of town twice a day at present.
My query is there some benefit in northern hemisphere countries to place panels on the same string west facing roof and some on vertical south facing gable end of garage that may take more gains in winter that i will loose on the E/W facing roof from Nov to Mar? thanks for all the useful info direction and recommendations folks.

phester28 · 18-05-2020 12:47pm

You cant (shouldn't) combine panels on different directions as the ones not producing would pull down the whole string to the lowest panel.

Now it is possible using optimiziers for each panel but that adds cost to your install. They would effectively disconnect or (more efficiently do a dc to dc conversion to match the normal production voltage but limit the current. Or some just put the lower producing into a high impedance (bypass mode)

Some brands optimiziers may do things differently and there may be a possibility of paralleling with bypass diodes the effective two strings (within one string). But I do not know enough about this to comment properly. Open to correction on any of these points

garo · 18-05-2020 1:42pm

gomamochi1 wrote: »

Thanks was on that website already though could not make sense of it. I am trying to maximise the solar gain as the system we are getting has 4.8kw pv panels with 4.8kw battery's and hope to charge EV at home some days and run the gaff off the batteries at night and remainder to go into the car at night when things get back to normal we will be doing more miles than we are presently just in out of town twice a day at present.
My query is there some benefit in northern hemisphere countries to place panels on the same string west facing roof and some on vertical south facing gable end of garage that may take more gains in winter that i will loose on the E/W facing roof from Nov to Mar? thanks for all the useful info direction and recommendations folks.

If you are asking whether you should put your two strings S, W instead of E, W the answer is we cannot tell unless you tell us your hourly usage pattern. Even an E/W system gives max output near solar noon. As mentioned by phester28, do not put different facing panels on the same string.

championc · 18-05-2020 7:20pm

gomamochi1 wrote: »

Thanks was on that website already though could not make sense of it. I am trying to maximise the solar gain as the system we are getting has 4.8kw pv panels with 4.8kw battery's and hope to charge EV at home some days and run the gaff off the batteries at night and remainder to go into the car at night when things get back to normal we will be doing more miles than we are presently just in out of town twice a day at present.
My query is there some benefit in northern hemisphere countries to place panels on the same string west facing roof and some on vertical south facing gable end of garage that may take more gains in winter that i will loose on the E/W facing roof from Nov to Mar? thanks for all the useful info direction and recommendations folks.

I think I know where you're coming from. In the northern hemisphere above about 45 deg lat, if you could rotate panels on one single axis to follow the sun, it makes more sense to rotate on the vertical rather than the horizontal. But South facing and vertical is indeed an option. If you could rig up something to tilt it slightly in steps every second month, that would be even better.

Remember though, output will be massively impacted until the point in the day when ALL panels can be hit by sunshine, so you'll get little or nothing until the last cell of the last panel on the West side is hit by sunshine, unless you fitted any shaded panel(s) with optimizer(s)

I think you also need to do your sums a bit more on the battery output. If the house consumes 500w per hour in the evening and 250w per hour after midnight, that's about 2kw possibly gone by midnight, and another 2kw by 8am. In addition, you'll get feck all for 4kw into an EV. For EV charging at night, forget about battery use an look at any power coming from night rate. Batteries are really only worthwhile to get you from dusk to nightrate start time. There's no point in batteries saving the payment of sub-10 cent kw units and as many will attest, even recouping the investment against full-price units is very doubtful.

Hope this helps

gomamochi1 · 18-05-2020 9:35pm

championc wrote: »

I think I know where you're coming from. In the northern hemisphere above about 45 deg lat, if you could rotate panels on one single axis to follow the sun, it makes more sense to rotate on the vertical rather than the horizontal. But South facing and vertical is indeed an option. If you could rig up something to tilt it slightly in steps every second month, that would be even better.

Remember though, output will be massively impacted until the point in the day when ALL panels can be hit by sunshine, so you'll get little or nothing until the last cell of the last panel on the West side is hit by sunshine, unless you fitted any shaded panel(s) with optimizer(s)

I think you also need to do your sums a bit more on the battery output. If the house consumes 500w per hour in the evening and 250w per hour after midnight, that's about 2kw possibly gone by midnight, and another 2kw by 8am. In addition, you'll get feck all for 4kw into an EV. For EV charging at night, forget about battery use an look at any power coming from night rate. Batteries are really only worthwhile to get you from dusk to nightrate start time. There's no point in batteries saving the payment of sub-10 cent kw units and as many will attest, even recouping the investment against full-price units is very doubtful.

Hope this helps

Thanks all very helpful. Agree that the night rate meter is most likely the only option at night for charging the EV. the thoughts of banging a couple of Kw's into her during the day purely from sun does excite me though if its at all feasible!! Maybe looking at increasing the amount of panels and batteries when china opens up again and can self install the rest. know of some Chinese producers with warehouses in Germany and a pallets 50e to Ireland so maybe an option later down the line also avoiding dreaded import duties!

Great info on the solar pv positioning and strings Thanks

n97 mini · 18-05-2020 10:09pm

garo wrote: »

Google PV-GIS. Ah here: https://ec.europa.eu/jrc/en/pvgis

But remember you are not just trying to maximize total output but output at the times you need electricity. No point having loads of output at noon when no one is in the house and then nothing at 6pm.

Yeah, no point in maximising output if you've no way to store it. E-W panels probably make more sense for most people than S. In Germany for example S facing panels are a thing of the past.

As mentioned above, the angle of the sun on the summer solstice is about 60 degrees, winter is 13 degrees (Dublin numbers), so ideally your panels should angled in between (36 degrees is half way).

Worth noting too that solar noon in Dublin isn't 12:00, but 13:22 in summer, 12:22 in winter.

gomamochi1 · 19-05-2020 8:35am

n97 mini wrote: »

Yeah, no point in maximising output if you've no way to store it. E-W panels probably make more sense for most people than S. In Germany for example S facing panels are a thing of the past.

As mentioned above, the angle of the sun on the summer solstice is about 60 degrees, winter is 13 degrees (Dublin numbers), so ideally your panels should angled in between (36 degrees is half way).

Worth noting too that solar noon in Dublin isn't 12:00, but 13:22 in summer, 12:22 in winter.

Cool, so my e/w roof is quite steep between 35/40 degrees this would suit. Thanks

Scoopsire · 19-05-2020 9:52am

Quote for install on a 2 story semi-d in Dublin, rear roof roughly faces south-west, though we also have smaller area facing south east

2.48 kW system (8 x 310 panels) standard inverter and hot water diverter - assume eddi (haven't received a breakdown yet)

Cost approx. €5,800 inc vat and allowing for the grant

First quote, will update with any others I receive

unkel · 19-05-2020 11:50am

That's expensive for a relatively small system without battery. Get another quote for a system with a small battery using your SE facing roof as well, can you fit at least 4 panels on it?

KCross · 19-05-2020 1:50pm

Scoopsire wrote: »

Quote for install ...

2.48 kW system (8 x 310 panels) standard inverter and hot water diverter - assume eddi (haven't received a breakdown yet)

Cost approx. €5,800 inc vat and allowing for the grant

WAY too expensive.

To give context... i have a quote for a 4.2kWp system (no battery, no diverter) for €4200 inc vat after grant.

You have a quote for a much smaller system for way more money! :eek:

Scoopsire · 19-05-2020 1:57pm

KCross wrote: »

WAY too expensive.

To give context... i have a quote for a 4.2kWp system (no battery, no diverter) for €4200 inc vat after grant.

You have a quote for a much smaller system for way more money! :eek:

@unkel will do

@KCross thought mine was poor, but it seems ridiculous compared to yours!
Would you mind PM me the company so I can reach out to them please?

garo · 19-05-2020 2:31pm

gomamochi1 wrote: »

Cool, so my e/w roof is quite steep between 35/40 degrees this would suit. Thanks

Yeah just plaster your E/W roof. Easiest and will give you pretty good output too.

bf · 19-05-2020 8:15pm

Have first quote in for Solar. Semi in Dub,in with south facing roof - given different options on panel makes:

- 4.4kw system, Denim 315w panels, Solax 5kw inverter €6,900 after grants or €9,200 with 5.8kw battery after grants

- 4.8kw system, LG 400w panels, 5kw inverter, €7700 after grants or €10,600 with 5.8kw battery

Seems a bit on the dear side?

garo · 19-05-2020 8:33pm

Expensive. The first system without battery should cost you 5k or less.

Geeyfds53573 · 22-05-2020 5:17pm

Hi - thanks again for all the help - could you clear up more questions I have please - If you had SE 120 degrees NW 300 degrees where would you put the majority/all the panels and could you direct me to a website that I could check this on? as may have to put on both sides - cheaper panels lesser watts on one side and more powerful panels on best side. I want to see projections for a variety of setups.

garo · 22-05-2020 6:04pm

Google PV-GIS to give you an idea of output. I would put more on the SE side but not madly lopsided. Note there are limits on each string so you wouldn't want to exceed those.

galah · 23-05-2020 4:50pm

Need some input please - just started getting quotes for solar panels, and was wondering about a few things.

Overall energy consumption is about 8000 kwh per year. However, half of that is on a night rate - am i right i only need a system that covers the day consumption (so max 4000 kwh per year)?

Was quoted prices without grant as we don't have a ber - would it be worth forking out for ber first to see if a grant makes sense? Installer didn't seem to think it was a good idea but didn't really tell me why. Also didn't quote me after grant prices, not sure why.

Quote came in at 7500 for 11 panels (300 watt, peimar) and diverte/eddi, no battery, no grant. I have a feeling that thats very high?

Just to say that everything in house is electric, including heating, someone is usually home all day as well.

TIA

unkel · 23-05-2020 5:18pm

That's a terrible quote. You are being ripped off. The installer perhaps was not a registered SEAI PV installer? This means he can't do a subsidised install. Maybe that's why he wasn't recommending it

galah · 23-05-2020 5:27pm

unkel wrote: »

That's a terrible quote. You are being ripped off. The installer perhaps was not a registered SEAI PV installer? This means he can't do a subsidised install. Maybe that's why he wasn't recommending it

Nope, they're seai registered, and feature fairly prominently when one does a Google search. Glad i checked - what would a rough ballpark be? And should i bother with the ber?

KCross · 23-05-2020 6:35pm

galah wrote: »

Overall energy consumption is about 8000 kwh per year. However, half of that is on a night rate - am i right i only need a system that covers the day consumption (so max 4000 kwh per year)?

It doesnt really work like that. If your idea is that you get a 4kWp system and hence your day consumption is now covered and going to be zero cost you are very much mistaken. There will be several months in winter where very little of your consumption is covered no matter how many panels you put up.

Ideally you want the system oversized so that you get more of your day consumption covered as you move closer to winter. That then has to be balanced against the cost and the space available.

galah wrote: »

Was quoted prices without grant as we don't have a ber - would it be worth forking out for ber first to see if a grant makes sense?

galah wrote: »

Nope, they're seai registered, and feature fairly prominently when one does a Google search. Glad i checked - what would a rough ballpark be? And should i bother with the ber?

The main reason to do the BER first is if you think that you cannot achieve a C rating after the SolarPV is installed. You need to hit that rating or no grant is given and no point in finding that out afterwards when the installer has been paid!

NOTE: Your house has to be built 2011 or earlier.

galah · 23-05-2020 6:50pm

KCross wrote: »

It doesnt really work like that. If your idea is that you get a 4kWp system and hence your day consumption is now covered and going to be zero cost you are very much mistaken. There will be several months in winter where very little of your consumption is covered no matter how many panels you put up.

Ideally you want the system oversized so that you get more of your day consumption covered as you move closer to winter. That then has to be balanced against the cost and the space available.

The main reason to do the BER first is if you think that you cannot achieve a C rating after the SolarPV is installed. You need to hit that rating or no grant is given and no point in finding that out afterwards when the installer has been paid!

NOTE: Your house has to be built 2011 or earlier.

Thanks! Of course i understand my daytime usage will still cost a bit, especially in winter - but i guess i can totally exclude the night usage in the calculation as the solar stuff won't cover it. Soit would make sense to get a 4 kwp system rather than a 8 kwp system to cover most of the daytime, correct?

House was built in 2003 so defo be ok for the grant.

I'm not sure what ber rating we'd have right now, so no idea if we'd hit the c or if we've that already.

garo · 26-05-2020 5:06pm

You should get a BER - it only costs ~200 Euro. Makes sense to do that before going for an install and finding out you are not eligible for the 3k subsidy. Most PV installers have a BER assessor attached so your installer should be able to tell.

No your idea of 4kWp for 4000kWh day usage does not work like that. Max solar output is in the summer and in the 4-6 hours around noon. You will use most of you electricity for cooking in the evening. For reference, my consumption was around 5400kWh with 30% night-time and I went for a 4.8kWp system with a 2.4kWh battery. Even so I will end up importing around 2600kWh from the grid for the year with ~50% nighttime as I have moved some usage to daytime to take advantage of solar production. So you need to over-provision if budget is not an issue. If money is tight go for a 4kWp system with a small battery - to get the full grant. If you want to maximize usage of solar and don't care about a longer payback time go for a 6kW system.

And yes your quote is very high.

ReadySteadyGo · 27-05-2020 7:47pm

KCross wrote: »

WAY too expensive.

To give context... i have a quote for a 4.2kWp system (no battery, no diverter) for €4200 inc vat after grant.

You have a quote for a much smaller system for way more money! :eek:

Can you pm me this company name please.

B9K9 · 28-05-2020 7:58am

Having wanted to design and built my own solar design from components, the timing now suits. Not wishing to make the ESB a present of free juice, I think I'll have a go at heating the soil beneath the house instead with the overproduction.

I will be ground mounting the panels in a field right beside the supply meter. Space and budget are relatively unconstrained.

I'm considering directly importing my panels, and possibly electronics as well, direct from China, so I'm interested to hear what people think, especially those who may have done something similar. Apologies if this is not the correct place to post.

championc · 28-05-2020 8:56am

What amount of panels are you looking to install ? You'd only be worth importing your own if you were buying a 40ft container load I would have thought.

You're better contacting someone like midsummer.ie or solartricity.ie and trying to do a bulk deal with them.

garo · 28-05-2020 10:43am

B9K9 wrote: »

Not wishing to make the ESB a present of free juice, I think I'll have a go at heating the soil beneath the house instead with the overproduction.

This does not make sense at all. The overproduction is a drop in the ocean for ESB. They honestly don't care. It's cut your nose off to spite your face thinking. Who cares if you are exporting for free? Find some good use for your electricity like an Electric Vehicle or heat a large cylinder of water.

unkel · 28-05-2020 11:15am

+1

And try not be so selfish and think about the environment for a second. For every kWh you send back to the grid, a little bit less gas will have to be burnt to generate electricity for others. I have sent several MWh to the grid for free myself

B9K9 · 28-05-2020 11:24am

garo wrote: »

This does not make sense at all. The overproduction is a drop in the ocean for ESB. They honestly don't care. It's cut your nose off to spite your face thinking. Who cares if you are exporting for free? Find some good use for your electricity like an Electric Vehicle or heat a large cylinder of water.

That actually is the correct priority. Of course I will recharge my Leaf first. Next heat the water cylinder. I reckon there will still be spare energy after all of that.

What's at all wrong with using the ground as a thermal bank? Only thing I see wrong with it would be ground water taking the heat away before it gets a chance to store the heat energy. Or it spreads out too much into the surrounding soil and is of little benefit.

If that saves me money and fuel, it will improve the payback time.

B9K9 · 28-05-2020 11:26am

unkel wrote: »

+1

And try not be so selfish and think about the environment for a second. For every kWh you send back to the grid, a little bit less gas will have to be burnt to generate electricity for others. I have sent several MWh to the grid for free myself

IF I store heat, that saves me fuel, your point has omitted that consideration. Only question is how cost effective it can be. I think its worth a go, because I think I can do it for minimal cost.

garo · 28-05-2020 11:28am

Yes and remember gas turbine units are only about 55% efficient in CCGT and 35-40% if Open cycle. Ireland has around half of each. So we are talking a lot of imported gas.

B9K9 · 28-05-2020 11:29am

championc wrote: »

What amount of panels are you looking to install ? You'd only be worth importing your own if you were buying a 40ft container load I would have thought.

You're better contacting someone like midsummer.ie or solartricity.ie and trying to do a bulk deal with them.

At the prices mention, a quare lot. FOB price $80 each. Add maybe 40-50% VAt Duty Freight. MOQ 25-30 in one crate.

garo · 28-05-2020 11:30am

B9K9 wrote: »

IF I store heat, that saves me fuel, your point has omitted that consideration. Only question is how cost effective it can be. I think its worth a go, because I think I can do it for minimal cost.

Do you actually spend money heating the soil around you? I'm curious as to how you recover or use that stored heat.

B9K9 · 28-05-2020 1:54pm

garo wrote: »

Do you actually spend money heating the soil around you? I'm curious as to how you recover or use that stored heat.

No, But (seasonal) thermal storage is a thing. I figure I can do it cheaply, so even if its only partially effective, I should be winning.

What I haven't been able to source is a programmable priority distribution switch. I think it would be ideal to choose each energy device for priority. e.g car or house or hot water 1, 2, 3, then spillover to ground what ever surplus remains.

garo · 28-05-2020 2:14pm

If you can do it cheaply and it works the rest of us would be very interested to hear. Resistance heaters are a rather expensive way of making heat. Are you going for some sort of heat pump? What do you estimate the thermal loss will be from say September to November?

gomamochi1 · 28-05-2020 7:01pm

Middle of install with a quote for solis hybrid inverter that will take up to 6kw of panels on roof. Currently getting 14 x 305 jasolar panels installed.
My query is the Solis 5kw hybrid inverter sufficient to take the extra panels at a later date. Only using one string as west facing currently.
The spec below is for the solis rhi-5k-48es which is currently installed in my attic. I thought I was getting a 6.6kw hybrid inverter? Any suggestions thanks for the advice.

gomamochi1 · 28-05-2020 7:08pm

gomamochi1 wrote: »

Middle of install with a quote for solis hybrid inverter that will take up to 6kw of panels on roof. Currently getting 14 x 305 jasolar panels installed.
My query is the Solis 5kw hybrid inverter sufficient to take the extra panels at a later date. Only using one string as west facing currently.
The spec below is for the solis rhi-5k-48es which is currently installed in my attic. I thought I was getting a 6.6kw hybrid inverter? Any suggestions thanks for the advice.

just looked them up and think that the max they go to is 5kw in single phase so that maybe my prob....

unkel · 28-05-2020 7:58pm

What orientation is the other string going when you upgrade to more panels? If east, then you will never go over the 5kW the inverter can handle. If south, you might want to think the inverter over. That said even in that situation with your largest string west facing, you will rarely go over the 5kW. And the few times that you do, so what?

garo · 28-05-2020 8:44pm

Says 2x11A with a voltage range of 90-520V. So you could get 5000VA on a single string but the combined output of the two strings cannot be more than 5kW. The inverter will just cut off any excess power above the 5kW.

gomamochi1 · 28-05-2020 8:46pm

unkel wrote: »

What orientation is the other string going when you upgrade to more panels? If east, then you will never go over the 5kW the inverter can handle. If south, you might want to think the inverter over. That said even in that situation with your largest string west facing, you will rarely go over the 5kW. And the few times that you do, so what?

East facing on the House roof. The Garage roof has shading from trees on the East roof. The Current panels 14 s 305w are on the West facing garage roof. Thanks

unkel · 28-05-2020 8:49pm

East west is perfect for self consumption. Any panels on your east facing roof that get any shade at all need an optimizer.

B9K9 · 28-05-2020 11:42pm

garo wrote: »

If you can do it cheaply and it works the rest of us would be very interested to hear. Resistance heaters are a rather expensive way of making heat. Are you going for some sort of heat pump? What do you estimate the thermal loss will be from say September to November?

No heat pump planned atm. More panels could be more bang for a buck instead, lower maintenance and complexity. But it's mainly to use up any over production. It's an experiment really, and I might be able to run it for about €1000 that's a smallish speculation.

garo · 29-05-2020 1:09am

At current gas prices that's 25,000 kWh of heating. Your thermal store would have to be doing very well to make that money back in less than 15 years.How much excess electricity would you generate annually? With 4.8 panels I am at 2700kWh but I don't have a diverter or an EV (yet).
Edit: This looks interesting: https://www.scanhome.ie/research/solarseasonal.php

B9K9 · 30-05-2020 10:18am

garo wrote: »

At current gas prices that's 25,000 kWh of heating. Your thermal store would have to be doing very well to make that money back in less than 15 years.How much excess electricity would you generate annually? With 4.8 panels I am at 2700kWh but I don't have a diverter or an EV (yet).
Edit: This looks interesting: https://www.scanhome.ie/research/solarseasonal.php

I did read that paper once. I had read about seasonal storage from way back over 30 years ago, when I had load of ideas but rather less money. And solar stuff prices offered poor or nonexistent financial return. Doing that to a good technical standard is bound to cost a packet, so no I won't go that road.

I will drill a hole 2-3m deep 50mm dia. beside and beneath the fireplace, and stuff a resistive element down there. I should probably make provision for varying the depth of the heater element(s).

Regarding number of panels, you need an oversized system to extend the benefits of solar deep into autumn, so thats why this will be DIY with labour counted at zero cost. I'm guessing a box of 27 from china as their MOQ for a start. Not on the roof; We have ample space free from shade in the nearby field.

Then when the current house demand, car charging, hot water and any battery store are all filled, the excess goes under the ground to warm the floor area and reduce the heat demand from elsewhere. Apparently some sytems take a very long time for the floor temperature to stabilise and thats where some long term data collection would come in handy. Probably a dedicated PC with a number of temp probes.

A thousand bucks seems a good speculative move. We spend that on energy in about six months I guess.

KCross · 30-05-2020 10:31am

B9K9 wrote: »

Then when the current house demand, car charging, hot water and any battery store are all filled, the excess goes under the ground to warm the floor area and reduce the heat demand from elsewhere.

I haven’t read the paper so tell me go read it if the answer is in there!

Any excess you have will be in summer. What use is heating the ground then when you won’t need that heat for months later. It will be long gone and possibly result in a house that’s too hot as the heats rises up through your floors like underfloor heating does.

Can you give me the crash course on how this works.

garo · 30-05-2020 12:57pm

A 3m deep hole with 50mm dia has a volume of 6litres. You sure you did not mean 500mm diameter? Even with 500mm you are only talking 600 litres. Let's assume you heat that water to 90C and then use it all the way down to 20 without any heat loss between the seasons. Wildly optimistic I know but bear with me. That is a total energy of 49kWh. I don't see how you save any money at all doing this.

And no way you maintain that temperature from summer to winter without loss. Please check the maths before sinking a 1000 euro in this project. It is looking less and less economically feasible. You will probably save a tenner off your bill every year.

tech · 01-06-2020 4:01pm

been tracking my usuage over the last few months, is this avg usage for a 4 bed detached.

Month Day Total Month Night

265 101
221 98
278 93
280 113
254 152
269 160

was thinking about gettin in PV, but the bills are loq and dont know would I see a pay back for 15+ years?

Domestic Solar PV Quotes 2020

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