Domestic Solar PV Quotes 2020

Kilough

Have read back through this thread looking for opinions on Solar PV for a new build but didn't find anything, did learn a lot though!

Basically I'm trying to set out a budget for a new build. My plan is to insulate heavily and hopefully achieve an A2 rated house. Will be heating the house with a vertical borehole ground source heat pump (COP ~ 5). I'm trying to figure out is it worth considering a PV array. I'll have plenty of roof space on southern aspect, maybe around 70m^2, how much power could I reasonably expect to generate daily throughout the year?

I wouldn't be eligible for a grant as it's new build but I guess I'd save on installation as I'd already have a roofer on site and could get it fitted by him and hooked up by the electrician. I'm told batteries have a long pay back period but again could do with some advice on this - maybe the Aliexpress imported batteries could make storage more viable?

Budget is tight enough but maybe worth borrowing that bit extra if the savings are worth it.

Any thoughts opinions on cost V benefit much appreciated!

championc

Kilough wrote: »

Have read back through this thread looking for opinions on Solar PV for a new build but didn't find anything, did learn a lot though!

Basically I'm trying to set out a budget for a new build. My plan is to insulate heavily and hopefully achieve an A2 rated house. Will be heating the house with a vertical borehole ground source heat pump (COP ~ 5). I'm trying to figure out is it worth considering a PV array. I'll have plenty of roof space on southern aspect, maybe around 70m^2, how much power could I reasonably expect to generate daily throughout the year?

I wouldn't be eligible for a grant as it's new build but I guess I'd save on installation as I'd already have a roofer on site and could get it fitted by him and hooked up by the electrician. I'm told batteries have a long pay back period but again could do with some advice on this - maybe the Aliexpress imported batteries could make storage more viable?

Budget is tight enough but maybe worth borrowing that bit extra if the savings are worth it.

Any thoughts opinions on cost V benefit much appreciated!

With a roofer available, I'd at least put up the clamps for rails. And you could earmark somewhere for an inverter, and run cables (or a flexibly conduit / tube to carry the cables) from the inverter location up to the roof. On the roof, start in a corner and work outwards. You don't want to be wasting space, just to have them looking nice and symmetrical.

With Solar PV, you need to look at trying to somewhat cover your base load on a poor day.

For qualities of power generated, look at the Monthly Stats thread, where you can get a good idea of the output from differently sized systems, from different parts of the country.

Alkers

championc wrote: »

With a roofer available, I'd at least put up the clamps for rails. And you could earmark somewhere for an inverter, and run cables (or a flexibly conduit / tube to carry the cables) from the inverter location up to the roof. On the roof, start in a corner and work outwards. You don't want to be wasting space, just to have them looking nice and symmetrical.

With Solar PV, you need to look at trying to somewhat cover your base load on a poor day.

For qualities of power generated, look at the Monthly Stats thread, where you can get a good idea of the output from differently sized systems, from different parts of the country.

Absolutely, I'd consider it madness to be doing a new build now and not to at least cater for putting them in in future. I'd get rails put up to cover pretty much the whole roof, panels are cheap and once FIT is introduced it might even make economic sense!

citizen6

Alkers wrote: »

Absolutely, I'd consider it madness to be doing a new build now and not to at least cater for putting them in in future. I'd get rails put up to cover pretty much the whole roof, panels are cheap and once FIT is introduced it might even make economic sense!

I would recommend getting it all done as part of the build, otherwise it could be years before you get around to doing it. Also if you have the solar pv shown on your plans then tradesmen know they need to allow for it when positioning water tank in the attic, locating the fuseboard etc.

unkel

If you get the rails up, you might as well fit the panels. Panels are dirt cheap. Two grand in panels will give you a huge array. That's not much compared to the cost of the house which is probably several hundred thousand.

Kilough

Thanks for replies.

Great thread on monthly returns people have been getting. Obviously looks like I could expect to generate vastly different power through the year. Maybe ill even look at re-orientating for max possible winter light!

Makes a lot of sense for me to at least provision for it but I will probably also install an array as large as makes sense. Not sure budget will stretch for a battery. I reckon by borrowing say an extra 6k to install an extensive array with inverter and all the associated fittings etc.,that will add around 30e a month to my mortgage payments at current (admitedly low) interest rates. Think it's definitely a worthwhile investment as long as it's done right, especially with possibility of selling back to trim down the line.

Some of the newer heat pumps claim to have inbuilt heat bank storage (Nibe) so maybe that could store some energy for me and output at night. Whenever I convert to EV, maybe in next 2 years or so, could look at adding a battery then.

Is it plausible for somebody without hands of experience to connect and power up an array system? Assuming roofer can attach, electrician can pull cables back to a central location. Is it then just a case of hooking up to a controller via an inverter? If I can save installation costs I will definitely give it a go.

championc

An EV won't justify a battery. Even my 10jkW of homemade LiFePO4 Powerwall will do fook all regarding charging my Kia e-Niro. However, my Powerwall does mean that I really use fook all expensive daytime units these days.

Not sure what you meant by connecting a controller to an Inverter. The PV panels + and - cables connect directly to the + and - ports on the interter. The live and neutral AC cables then connect from the inverter to their own RCBO in the fuse board.

The hardest part of a DIY install is the roof. The rest is just being handy with a screwdriver

Kilough

championc wrote: »

An EV won't justify a battery. Even my 10jkW of homemade LiFePO4 Powerwall will do fook all regarding charging my Kia e-Niro. However, my Powerwall does mean that I really use fook all expensive daytime units these days.

Not sure what you meant by connecting a controller to an Inverter. The PV panels + and - cables connect directly to the + and - ports on the interter. The live and neutral AC cables then connect from the inverter to their own RCBO in the fuse board.

The hardest part of a DIY install is the roof. The rest is just being handy with a screwdriver

Seems relatively simple. I guess I thought there might be more to it seeing as most people appear to be hiring professional installers. Assuming now that there was no government grant aid that DIYing it would be more common.

The powerwall might be an addition down the line, will see how my usage looks and then maybe invest in one. Assuming I'll install one down the line, are there any provisions I should take during construction? Best location might be the attic and then just a couple of extra cables routed back to the fuse board?

Also, is there any benefit to a 3 phase supply over single phase? It's been asked before but couldn't see an answer.

graememk

Kilough wrote: »

Also, is there any benefit to a 3 phase supply over single phase? It's been asked before but couldn't see an answer.

Basically more power. 3+n power wires coming into your house instead of 1+n all 120° out of phase with each other

Could be a benefit if you are getting large heat pumps. But generally they are inverter driven now.

Bigger motors need three phase too.

A enchanced supply is 16kva now but you can get 20kva now too. - all single phase.

A good few of the new evs can charge on three phase too. So your talking about 11kw instead of 7kw

KCross

Kilough wrote: »

Also, is there any benefit to a 3 phase supply over single phase? It's been asked before but couldn't see an answer.

In terms of Solar PV it means you can export more to the grid.... 11kW vs 6kW.
When FiT arrives you will get paid for more of your excess Solar so if you plan to put in a large array it would be better to have 3ph instead of 1ph but the gotcha is that 3ph tends to cost alot more to get into a house.

You'll need to talk to ESB and get a quote for getting 3ph connected.... it might not cost much extra or if you are a long way away from the 3ph network it could be thousands extra.

championc

And any specific 3 phase devices would cost more than single phase

slave1

Pretty sure (but open to correction) the Tesla Wall Charger is same price whether single or three phase

graememk

slave1 wrote: »

Pretty sure (but open to correction) the Tesla Wall Charger is same price whether single or three phase

arent all of them 3 phase and just configured for single phase?

Caspero

Kilough wrote: »

Also, is there any benefit to a 3 phase supply over single phase? It's been asked before but couldn't see an answer.

In addition to a larger solar system (11kw vs 6kw max on single-phase), 3 phase allows you to install a faster EV charger - up to 22kw EV charging is possible with a 3phase supply although only a couple of today's EVs can charge at that speed. More will come over time.

Some people say you don't need faster than 7kw charging which is possible with single-phase because that'll charge your car overnight, but people are human and sometimes forget or have an emergency and need power in the car in a hurry so it's nice to have. Just a cost/benefit decision that each person has to make for themselves.

It's not cheap to retrofit for a 3-phase supply. The ESB part will probably charge you 2.5 k to 3.5k to upgrade the supply at a minimum and that's if you're near a supply line with enough power to supply 3 phase. It'll cost well upwards of that if not because they base the cost on your distance from the supply line. Then you need a new meter box because the old ones are too small. You also need a new trench dug from the supply line to your meter to install a new duct because ESB require a 125mm duct for 3-phase which is far bigger than the single-phase ducts. Overall 5k+ to upgrade the supply.

unkel

Caspero wrote: »

In addition to a larger solar system (11kw vs 6kw max on single-phase), 3 phase allows you to install a faster EV charger - up to 22kw EV charging is possible with a 3phase supply although only a couple of today's EVs can charge at that speed. More will come over time.

Some people say you don't need faster than 7kw charging which is possible with single-phase because that'll charge your car overnight

My car is over 6 years old, but it has a 85kWh battery, so I would need 3-phase to charge it from empty to full within the night rate period (of 9 hours)

If I had 3-phase (and a very large solar PV array), I would almost certainly install a 22kW charge point. They barely cost any more than 7kW single phase charge points - something a lot of people aren't aware of.

Gumbo

Is there a market for second hand Solar PV Invertors?
Took out my old Trannergy Invertor as I got a GivEnergy battery set up recently.

Deagol

Gumbo wrote: »

Is there a market for second hand Solar PV Invertors?
Took out my old Trannergy Invertor as I got a GivEnergy battery set up recently.

Snap! Same here - looking to offload a Trannergy 2kw if anyone knows anyone / anyway to get shot of to someone?

Or alternatively is there any usage I could make of it?

Gumbo

unkel wrote: »

My car is over 6 years old, but it has a 85kWh battery, so I would need 3-phase to charge it from empty to full within the night rate period (of 9 hours)

If I had 3-phase (and a very large solar PV array), I would almost certainly install a 22kW charge point. They barely cost any more than 7kW single phase charge points - something a lot of people aren't aware of.

My old bmw wallbox was 3 phase and 22kw ready. That was a cheap purchase at 220e. So deffo possible at not any additional cost, once the 3 phase connection is there.

Food for thought for anyone building a new house themselves and 3 phase is available.

DrPhilG

I'll be looking for another inverter in the next few years but 2kw won't cut it for me sadly.

I'm sure you'd get some takers though.

Gumbo

DrPhilG wrote: »

I'll be looking for another inverter in the next few years but 2kw won't cut it for me sadly.

I'm sure you'd get some takers though.

I’ve a 3.4 one there

A Trannergy SGN3400TL.

Is there any cool side projects we can use these for?

slave1

unkel wrote: »

My car is over 6 years old, but it has a 85kWh battery, so I would need 3-phase to charge it from empty to full within the night rate period (of 9 hours)

If I had 3-phase (and a very large solar PV array), I would almost certainly install a 22kW charge point. They barely cost any more than 7kW single phase charge points - something a lot of people aren't aware of.

Ah Unkel, 85 is the model number not the battery size, think that slipped your mind, battery when brand new was 81.5 with 77.5 usable, with typical degradation yours is close to 72/68 now

unkel

I know that dude, still can't fill it up with night rate when it's empty. Or did you not understand that was the point I was making? Plugged it in at 15% last night, needed full charge this morning and it was still not quite full (97%) when I drove off at 8:30 (so it had been charging for half an hour already at the full day rate)

Gumbo wrote: »

Is there a market for second hand Solar PV Invertors?

Deagol wrote: »

looking to offload a Trannergy 2kw if anyone knows anyone / anyway to get shot of to someone?

Stick it on adverts. Very few for sale but some people might be looking. I sold several of my old inverters there. With my own plans for this spring, I will either need to get an additional inverter, or sell my current one, a 3.6kW Solis dual MPPT

slave1

I did, my OCD on the "it has a 85kWh battery" comment is what I was responding too, plenty of other folk out there thinking a 5/6 year old Model S 85 has a 85kWh battery so simply sharing the knowledge is all

SouthWesterly

A quick question for those who got the solar as a service deal.
What daily output are you getting these days?

Alkers

SouthWesterly wrote: »

A quick question for those who got the solar as a service deal.
What daily output are you getting these days?

6.4kWh today, 33kWh since installed on 12th Dec

phester28

Alkers wrote: »

6.4kWh today, 33kWh since installed on 12th Dec

DOes not tell much unless we know your size / orientation

My 2.4KW east west split (1.5:0.9) only made 1.1KWH today. or a total of 16.4KWh to date in December

Alkers

phester28 wrote: »

DOes not tell much unless we know your size / orientation

My 2.4KW east west split (1.5:0.9) only made 1.1KWH today. or a total of 16.4KWh to date in December

2.52kW (as is the solar as a service offer) due south

MAULBROOK

6.2kw panels south east in wexford
Generated 9.8kw today
Total this month 100.1kw
Not bad for December and a short day

Deagol

I'm only making 2.3kwh at the moment on my 6.1kw system I have shadow from the house blocking a lot of the sun at this time of the year. I'm working on an idea to rise up the panels a bit to try and help.

irishchris

SouthWesterly wrote: »

A quick question for those who got the solar as a service deal.
What daily output are you getting these days?

2.7kwh today on a dull day with 51kwh produced this month