EVs and solar panels

CoBo55

https://www.boards.ie/discussion/comment/121151218#Comment_121151218

Hmmm, battery storage with no solar... that's worth considering especially with that rate.

the_amazing_raisin

https://www.boards.ie/discussion/comment/121152055#Comment_121152055

Tbh the battery and hybrid inverter are pretty expensive by themselves so it'd be hard to justify the cost without the panels

No SEAI grant either to soften the blow

unkel

https://www.boards.ie/discussion/comment/121152131#Comment_121152131

I sold a no-name 5kWh battery pack a few months ago for €895. Buy a Sofar ME3000SP for about €600 and have an electrician hook the inverter up to your consumer unit for €150. The battery is click and play with the inverter. Take in 5kWh into the battery every night for 5c and release it for 28c on a timer. That's a revenue of 23c * 5kWh * 365 days or €420 per year, say 20% conversion losses for both ways, so €335 per year (tax free if 2 people on the bill), that's a pay back period of under 5 years, or a tax free return on a low value low risk investment of over 20%

Imagine what the pay back period is if you have a bigger system, buy your equipment much cheaper than that, build your own batteries and have a mate RECI who hooks things up for free. I bet you believe me now when I tell you it is more like 2-3 years

Dayor Knight

Even if you don't charge your car using the solar it can make some of the smart plans more advantageous. E.g. charge the car at night or weekend (free Sat/Sun with EI/BG) and use the solar to reduce the impact of the higher rates you will likely be paying the rest of the time..... everyone needs to run their own numbers.....

graememk

https://www.boards.ie/discussion/comment/121152131#Comment_121152131

I've run the numbers, and the payback is surprising

Say 2500 for 14kwh, 5-600 for an inverter, even at flogas community rate at 33 day 14.75 night, cycle to 20% is 11 and change

20% losses, (I've measured that over 2 yrs now)

Buy 13.2(€1.94) to get 11 out (€3.63)

1.68/day that's over 600/yr.

CoBo55

https://www.boards.ie/discussion/comment/121157552#Comment_121157552

I got lost after 14.75 night...

unkel

https://www.boards.ie/discussion/comment/121158190#Comment_121158190

I'll try make it a bit simpler, maybe that helps?

For Pinergy. Buy at 5c, sell at 28c

Graeme's system has 14kWh, of which he has 11kWh as usable (that's very conservative), so you can load up 11kWh per day and sell it. You will have about 20% losses, so 11kWh minus 20% is 9kWh. So you make 9kWh (28c - 5c) per day times 365 days = €755 per year

The system cost €3300 to install (including €200 fee for an electrician that Graeme didn't include), so a pay back period of about 4-5 years

Mr Q

https://www.boards.ie/discussion/comment/121158442#Comment_121158442

But you are leaving out some figures too. That €755 is taxable, less your €200 credit if one name on the bill. So it could be €755 less roughly €270 leaving €485.

Plus wear and tear or replacements in that time. That payback would get much closer to 8-10 years very quickly if accounting for everything.

And the the Pinergy buy at 5c, sell at 28c is great now but who knows what will be there in 18 months.

Saying that I have batteries and would buy again if doing it now for several reasons, payback being one.

unkel

https://www.boards.ie/discussion/comment/121158740#Comment_121158740

It's taxable but there is a €200 per person exemption on the bill. I have 5 people on the bill 

😂



Inverter and battery should last 10 years without maintenance. So after the system has paid off itself in 4-5 years, the next 5-6 years are pure profit of €755 per year. Also this cost was for an assembled system, paying an electrician and going rates for parts. Personally I buy a lot cheaper than market rates, build my own system and have a mate electrician, so go figure the payback period is more like a bit over 2 years rather than 4-5 years

And indeed, nobody knows where the rates are going, but it is near certain that the difference between peak rate and cheapest rate is getting bigger, not smaller. That is natural in the transition to renewables (feast or famine). Not so sure if this generous FIT regime is going to last though...

Mr Q

https://www.boards.ie/discussion/comment/121158784#Comment_121158784

But it is not realistic for most to put 5 people on their bill. I had thought it was a max of 2 but obviously not.

I'm surprised the FIT has got anywhere near as high is it is currently, fully expected the energy companies to pay a tiny amount per unit.

unkel

@Mr Q - "I had thought it was a max of 2 but obviously not."

Same. If you remember most of us here weren't expecting much more than wholesale rates of about 5-6c around the time just before the first providers started announcing FIT rates. That said, they make a lot more profit on all other rates these these than they did a few years ago. Looks at the profits of the utility companies.

@Mr Q - "But it is not realistic for most to put 5 people on their bill."

Any 16+ year old in the house with a job can be put on the bill as you can claim they pay towards said bill from their earnings

the_amazing_raisin

https://www.boards.ie/discussion/comment/121158810#Comment_121158810

I expect as solar becomes more popular then the FIT will begin to drop, like what has happened in pretty much every other country

It's important to remember the suppliers are still making a profit on the FIT, if they're buying it at 28c they're also selling at 47c or so back to the market

Same for that pump and dump that unkel is talking about, customer buys at 5c in the middle of the night and supplier makes a profit (albeit probably a very small one). Customer sells electricity at 28c during the day and supplier still makes a profit reselling that

cannco253

slightly off topic, but do we know how much energy FIT provides/has provided to the Grid - are those figures available or buried?

https://www.smartgriddashboard.com/#all/generation

System Generation

System Generation represents the total electricity production on the system, including system losses, but net of generators' requirements. It includes an estimate of the power produced by wind generators, but excludes some non-centrally monitored generation (e.g. small scale combined heat and power and microgeneration).

Calahonda52

https://www.boards.ie/discussion/comment/121150546#Comment_121150546

Once you get out to the high mileage end of the curve EVs are not at the races due to the finite life of the battery.

Am looking at a 25 year old 2.8 V6 l Volvo estate in Margate at the moment: 1,200 stg: in immaculate condition inside and out, full service record for the 450,000 miles on the clock: put up on blocks for for 5 years, till it gets to 30, beats 15% inflation

unkel

https://www.boards.ie/discussion/comment/121160714#Comment_121160714

There's no such thing as a set lifespan, finite life of a battery. They will last much longer than the rest of the car. They will degrade but this is a slow process (except in a Nissan Leaf). It is standard in the spec sheet of any battery cell to state the number of cycles of life. But this is not until the cell is dead, it is until the cell "only" has 80% capacity left. In the case of LiFePO4, this is generally 6000 cycles. Or in practical terms, a car with say a 60kWh battery that does two cycles a week, can have 3000 weeks until it is has lost 20% capacity. That's roughly 60 years and 2 million km

You've been a regular in this forum for many years, surely you would have picked up on this sort of stuff along the way?

the_amazing_raisin

https://www.boards.ie/discussion/comment/121160714#Comment_121160714

How many of the parts in that Volvo have been replaced in the 25 years? 😉

Because if it's had any significant parts replaced then that's going to be several thousands invested in repairs

And if it's okay to spend several thousand keeping an ICE running for 25 years (I think it is fine to be clear) then it's also okay to spend several thousand on replacing degraded battery modules in a 25 year old EV

unkel

https://www.boards.ie/discussion/comment/121161067#Comment_121161067

The whole point is that an old ICE need expensive maintenance / fixes to keep going. The old EV needs nothing. Nobody in their right mind is going to spend serious money to replace degraded battery cells with shiny new ones. If the range is no longer sufficient, you just sell it on to someone for whom the range is no problem

And yes I know there are loads of eejits queuing up to pay thousands for newer / bigger batteries for their old Leafs and anyone can do with their hard earned what they like, but those are not rational decisions...

the_amazing_raisin

https://www.boards.ie/discussion/comment/121161151#Comment_121161151

I think replacing modules could be viable if done for the right price

They won't be new batteries for sure, unless we see a shocking change in approach from manufacturers who don't make the modules available for sale

Just did some quick googling and a 2nd hand ID.4 module can be bought for €1,250 with a capacity of 6.82kWh when new

https://evshop.eu/en/batteries/339-vw-id3-battery-module-48v-12s-685kwh.html

Not the greatest price ever, but bear with me for a second

You could probably DIY the module replacement, hardest part is getting the battery pack out without getting squished

After that it's just pop the screws out of the cover, open the pack and disconnect the bad module

How many modules would it take to maintain 70% capacity in the car over 25 years? Could be zero, but two or three seems possible if some of the modules degrade faster

Let's say 4 modules because it multiplies easier and maybe you got a bit of a lemon of a car

So €5k over 25 years, €200 a year average to keep a lemon on the road

That's not bad when you think about it, could easily see a petrol car costing twice that and be considered cheap to maintain

So even in a bad scenario of the battery needing a bit of work it's still possible to do it cheaper

I do agree a full pack replacement is almost never going to make sense. Maybe if doing it DIY on a classic, but I don't really see the appeal of spending €9k to upgrade a 2011 Leaf to 200km of range

sh81722

https://www.boards.ie/discussion/comment/121161605#Comment_121161605

Devil's advocate here: The classic EVs have advantages though and this is before thinking about sustanability of throw away tech including cars.

I find the 2016 leaf less annoying than the 2018 model due to lack of lane assist and collision warnings. The 2021 Model 3 doesn't seem to suffer though, but the new models introduced in 2023 now have speed warning pongs if you go even 1 km/h over the speed limit (that the car thinks is right, which may or may not be the correct speed) that have to be switched off at the start of every single jorney. That would be even more annoying.