Solar PV, is it worth it?

micks_address

Yeah I'd stay clear of thermal.. brother has had nothing but hassle with his...

JayBee66

https://www.boards.ie/discussion/comment/121159304#Comment_121159304

I wouldn't put solar thermal on the back of anything. It really needs direct midday Sun to be of any use.

We have legacy thermal, which provides hot water from May to August. The rest of the time it's only pre-heating water for the immersion heater to top up. Still, it means we export more electricity for the winter months.

However, if we didn't have it before the PV then we wouldn't install it now. There are maintenance costs too. The anti-freeze in the pipes has to be changed every few years. If there's a major fault requiring replacement equipment then we would probably remove the thermal panels and replace them with two more PV panels.

Kealyboy

Here is the quote I received the battery is listed in this quote but is €2500 on top of price listed on quote.

just skimming through thread some someone saying 430W panels ain’t great… should I be looking for bigger?

I am looking to go down the EV and heat pump route in the near future…

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UnhappyCustomer

https://www.boards.ie/discussion/comment/121150943#Comment_121150943

If you boost the immersion at night, will you have hot water all day? Say an hour or 2 from 4 am to 6 am or do you need to top it up during the day?

I have an Eddi but I'm thinking that selling the extra and boosting the hot water during the night would be the best decision

micks_address

https://www.boards.ie/discussion/comment/121227232#Comment_121227232

Depends on your tank insulation and usage. I heat ours with the gas in the morning for an hour between 6 and 7 and it tends to hold hot all day. The Eddi kicks in a little some days. Fitted a new pre insulated tank in may

UnhappyCustomer

https://www.boards.ie/discussion/comment/121227337#Comment_121227337

The tank, immersion and eddy are new and the use would be to avoid freezing our hands during the day and showers during the night. I’m concerned about not having enough hot water during the night if I just boost it during the early morning (4 or 5 am)

micks_address

https://www.boards.ie/discussion/comment/121227376#Comment_121227376

Why not try it and see?

JayBee66

https://www.boards.ie/discussion/comment/121227232#Comment_121227232

As @micks_address says, it depends on usage. For showering we have an electric shower running off the battery on the lower power setting as close to solar transit (12:35 GMT/13:35 IST,) which means we either import around 100W or it all comes off the battery. If you don't have a battery then you won't achieve that.

If there's enough sunshine I'll boost the tank to 55C at around midday (otherwise cheap rate electricity at 7AM to 8AM) and that suits us for our sink needs but I doubt it would be enough for a power shower. Unless, like herself, you take a "navy shower"; wet yourself, shower off, lather yourself, shower on to rinse and then off again. The shower is barely on for on for 3 minutes. If there's enough warm water in the tank then I tend to use the bath and fill a small bucket with water and chuck it over myself. I've lived off-grid and lived outdoors a lot so that suits me fine.

Our ways might not suit others. PV owners come in a spectrum from those making best efficient use of every Watt to those who prefer to forget about the PV once installed and live anyway they please. It all depends on how fast you want a return on your investment, if at all.

unkel

@UnhappyCustomer - "I have an Eddi but I'm thinking that selling the extra and boosting the hot water during the night would be the best decision"

If you are on a smart meter with a very low night rate and a high feed in tariff, then yes indeed. Busy house here with 360l hot water cylinder. I run the eddi for 3 hours every night between 2AM and 5AM, only costing me 5c / kWh. This wouldn't even be enough were it not for my 40 tubes of solar thermal helping to heat the water too, from the bottom up.

During the day, my eddi is inactive and pretty much all my PV goes straight to the grid, for which I get paid 28c / kWh

DC999

https://www.boards.ie/discussion/comment/121227408#Comment_121227408

+1 to mick, suck it and see. Let others in the house know and you'll know soon enough if not working

wibago

Hoping for some knowledge on domestic solar power.

Now to start, I know the tarriffs are less favourable now than what it used to be, BUT.... The way energy prices are going, and the way the future looks, some degree of self sufficiency and future proofing cant be bad?

The price cap is going up, I think history tells us that prices dont come back down to where they were following a surge, even IF the reasons for the surge get better.

So that leaves us with a straight up "is it worth it" question. I would be looking to buy them so no concerns over shady lease arrangements.

I would look to acquire as many panels as I could aswell as a solar battery, as I believe currently with prices as they are, the money is in what you dont buy from the grid as opposed to what you export (for which you are paid, but at a less favourable rate than years gone by.)

One issue that I have heard of that I am unsire still exists is charging EVs on a system containing a solar battery. I dont currently have an EV, but lets face it, one day I will.

Again, in terms of future proofing, I hear my home with gas. I would assume that one day, possibly when my boiler goes, I could install an air source system and run it off my own power, and at that point become almost fully energy self sufficient. Am I missing anything stupid? Does anyone have experience in this?

wibago

https://www.boards.ie/discussion/2058319950/solar-panels

appreciate any help with this. thanks in advance

graememk

https://www.boards.ie/discussion/comment/121293232#Comment_121293232

Is it worth it? Yes. As long as you don't overpay for it.

You mention price cap and export rates being poor? Are you UK based?

Here, the feed in tariff has just started, and it's pretty good(20-24c), and we don't have a price cap here.

No issue with EV/solar/batteries, jury is out on batteries and hot water diverters now though, because the feed in is good.

It's not that heatpumps and solar don't mix, it's usually when you want heat it's not sunny! Batteries could be a way to load shift onto cheaper rates though. You could also build up credit in the summer to pay for the electric in the winter, that's also the case for gas/oil.

jkforde

you won't regret going for solar!

at this point in time, don't bother with an off-the-shelf battery and just export any surplus (use the grid as your battery!)

do you have a day\night meter? if so, you can charge the EV at night rate which can be cheaper than using your solar surplus.

for domestic hot water, just use an immersion timer

good luck with it!

kaymin

I would get solar but neighbours trees shade part of my roof midday and I understand the entire array generates at the lowest of all the cells in the array at any point in time even if 90% is bathed in sunshine. Am inclined to raise it with the neighbours but then I'm only a blow-in...

unkel

https://www.boards.ie/discussion/comment/121297848#Comment_121297848

You could use optimizers or micro inverters. Both will limit the effect of shading only to the panels with actual shade on them. The rest of the panels will generate as normal. Adds lots of points of failure though and is more expensive, so your pay back period would be longer.

Personally, I'd ask the neighbours in a friendly way, offer to pay for the trim down of the trees causing shade

graememk

Most panels now have bypass diodes, hard shadows would bypass the affected panel, eg chimneys. Sometimes trees.

Optimisers really only work for diffuse shadows.

Would it still be shadowed in summer?

kaymin

https://www.boards.ie/discussion/comment/121298769#Comment_121298769

It wouldn't be shadowed in summer but now / Autumn and over the winter months when the sun is low it would be partially shaded midday when I'd be hoping to generate the most power. I'm considering a 12 panel array and expect half of the panels would be affected. Am inclined to ask the neighbours and decide on solar based on the outcome.