Can you run an all electric house for free?

greenbee

I've had negative bills since installing my second lot of solar (but that was April, so no winter bills yet). I also moved from Octopus Flux to Agile. I've got a 10kWh battery, and the inverter supports one circuit in the event of a power cut (we had one for 30 minutes a couple of weeks ago and it did it's job happily). 

My DD is set by Octopus to £0.00. And between the new panels going on and the end of September I've been refunded around £1400. October is the first month I haven't requested a refund, as while the bill was negative, it wasn't huge, so I'm going to start building up credit in case my imports start to outweigh export. It'll be interesting to review after a full 12 months. 

Qyburn

Solarchaser said:

Total export was 13256Kwh at 15p/Kwh 

I just picked that up, the figure suggests quite a large solar array, maybe something like 12kWp. Which is interesting because I thought FIT only permitted up to 4kWp. Or maybe only paid out on 4kWp.

crumpet_man

I may have missed it, but has anyone mentioned their investment cost for solar and batteries?

No doubt one can run an all electric house for free if the upfront costs are ignored.  How long does it take to recoup that investment?  What is the lifespan of the solar panels, batteries and related equipment?

Solarchaser

Qyburn said:

Solarchaser said:

Total export was 13256Kwh at 15p/Kwh 

I just picked that up, the figure suggests quite a large solar array, maybe something like 12kWp. Which is interesting because I thought FIT only permitted up to 4kWp. Or maybe only paid out on 4kWp.

My Fit solar array is the standard 4Kw, I also have another solar array not on fit, combined they provided 7500Kwh in that same time period.

However I also have the batteries set to discharge at certain times during the day, and their combined total out output over that time period was 13222Kwh

So if we assume that all of the solar was exported at 15p, then the remaining export was from the batteries was 5722Kwh.
Having bought this at 7p and with a 9% loss round trip, (on my lux inverters) it cost £437 to charge and I earned £858 from the discharge so a profit (bill reduction) of £421

Which also means that the rest of the batteries batteries output was covering the house load at 28p/Kwh so the 7500 x1.09 x0.07 = £572 cost to charge and a saving of £2100 which means a profit (bill reduction) of £1528 just through the batteries.
The other 7500Kwh exported at 15p "made" £1125

In reality some of the solar in the shoulder months would have been house consumption, most in the winter months would have been house consumption and the vast majority in the summer would have been exported.
There's no real way to determine which contributed to export rather than house usage at a particular point, but i can say with some confidence over 80% of the solar went to export, and so the figures are close enough to argue about.

The zappi charged cars with about 14400miles, assuming 3 miles /Kwh. Better to be conservative with these figures.

I apologise if this doesn't read right, and please feel free to pick up errors, seem to have picked up a bit of a cold/whatever. But didnt want to not respond

Solarchaser

crumpet_man said:

I may have missed it, but has anyone mentioned their investment cost for solar and batteries?

No doubt one can run an all electric house for free if the upfront costs are ignored.  How long does it take to recoup that investment?  What is the lifespan of the solar panels, batteries and related equipment?

Hi my investment in solar panels was £7000 for 4Kw FIT panels back in 2014, id expect you now to be able to get 4Kw for around £4k based on several friends buying them recently, around now is probably your best time for deals, as we head into winter.
It paid itself back between the Fit rate and household savings in about 4-6 years id say.

I then bought 6.6Kw of solar panels and a couple of ebay inverters in 2019 and self installed those for around £2k, they paid back within 2 years.

I bought batteries and inverters in 2019 totalling around £8k.
I've since sold on all of those batteries for (I think) about £5k and bought cheap Chinese ones for about £7.5K, which for the same batteries is now £5400

So id put myself around £12.5k in the hole for the last 6 years of messing around

If I went back to 2018 and assumed my usage stayed the same, id currently be paying £1000/ year for gas and £1500/ year in electric, as well as running a petrol car and it's associated costs.

So £2500/ year vs -£200 / year just now if we remove the electric cars for a fair comparison.

Looks like around a 5 year payback, less if I was starting now, but with the caveat that except for the original FIT solar install, everything else has been DIY, and thats not feasible for all, but you asked for my case, so here it is.

My FIt solar panels are 11 years old and dont seem to be suffering any degradation. 
The inverter went under warranty and was replaced and so far (touch wood) has been fine.

The battery inverters are 6 years old and touching more wood have been flawless.

The new cheap Chinese batteries (fogstar) are trending at 98% capacity for one set (eve 280's) of B rated cells and 103% for the other (envision 305's) set of B rated cells after around 650 cycles each.

Comparatively the Tesla 3 i have been driving the last 4.5 years was initially able to use 70Kwh, but over the last year has never used more than 63Kwh, so a 10% drop off in around 380 cycles, and these are supposed to be the top of the line A rated cells.

It's not a straight comparison obviously,  but i was seriously disappointed in the Tesla and quite pleasantly surprised by the fogstar.

Martyn1981

And there's also the tax side to consider, which hit the news a few days ago.

Over 18,000 UK solar panel owners could face £100 HMRC fine this Friday

Thousands of UK homeowners with solar panels could be hit with unexpected £100 fines this week as the HMRC paper tax return deadline approaches.

Many are unaware that income earned from selling unused solar energy back to the grid could push them over the £1,000 tax-free trading allowance.

With the deadline falling on Friday, homeowners are being urged to check their earnings now to avoid costly penalties.

Of course, not applicable to the majority with small(ish) export earnings.

Ectophile

Martyn1981 said:

And there's also the tax side to consider, which hit the news a few days ago.

Over 18,000 UK solar panel owners could face £100 HMRC fine this Friday

Thousands of UK homeowners with solar panels could be hit with unexpected £100 fines this week as the HMRC paper tax return deadline approaches.

Many are unaware that income earned from selling unused solar energy back to the grid could push them over the £1,000 tax-free trading allowance.

With the deadline falling on Friday, homeowners are being urged to check their earnings now to avoid costly penalties.

Of course, not applicable to the majority with small(ish) export earnings.

It's also worth knowing that FIT payments are tax free, but you may get taxed on export payments.

JKenH

Martyn1981 said:

And there's also the tax side to consider, which hit the news a few days ago.

Over 18,000 UK solar panel owners could face £100 HMRC fine this Friday

Thousands of UK homeowners with solar panels could be hit with unexpected £100 fines this week as the HMRC paper tax return deadline approaches.

Many are unaware that income earned from selling unused solar energy back to the grid could push them over the £1,000 tax-free trading allowance.

With the deadline falling on Friday, homeowners are being urged to check their earnings now to avoid costly penalties.

Of course, not applicable to the majority with small(ish) export earnings.

That’s a blow having just ordered a Powerwall and another 5kW of panels. Looks like I will have to self consume more. Last year I earned £580 on Flux exporting 3680 kWh of my 4779 generated and this year (mainly Agile) I am at £572 from 3923 kWh exported (£5158 generated). I don have any side hustles although my eBay sales YTD are over £2k. 

I was hoping with the Powerwall and a summer on intelligent Flux to earn over £1500 next year. Perhaps I need to get an EV.

JKenH

Ectophile said:

Martyn1981 said:

And there's also the tax side to consider, which hit the news a few days ago.

Over 18,000 UK solar panel owners could face £100 HMRC fine this Friday

Thousands of UK homeowners with solar panels could be hit with unexpected £100 fines this week as the HMRC paper tax return deadline approaches.

Many are unaware that income earned from selling unused solar energy back to the grid could push them over the £1,000 tax-free trading allowance.

With the deadline falling on Friday, homeowners are being urged to check their earnings now to avoid costly penalties.

Of course, not applicable to the majority with small(ish) export earnings.

It's also worth knowing that FIT payments are tax free, but you may get taxed on export payments.

So are you suggesting deemed export will be taxable as well as metered export? I never understood why FiT was tax free.

greenbee

JKenH said:

Martyn1981 said:

And there's also the tax side to consider, which hit the news a few days ago.

Over 18,000 UK solar panel owners could face £100 HMRC fine this Friday

Thousands of UK homeowners with solar panels could be hit with unexpected £100 fines this week as the HMRC paper tax return deadline approaches.

Many are unaware that income earned from selling unused solar energy back to the grid could push them over the £1,000 tax-free trading allowance.

With the deadline falling on Friday, homeowners are being urged to check their earnings now to avoid costly penalties.

Of course, not applicable to the majority with small(ish) export earnings.

That’s a blow having just ordered a Powerwall and another 5kW of panels. Looks like I will have to self consume more. Last year I earned £580 on Flux exporting 3680 kWh of my 4779 generated and this year (mainly Agile) I am at £572 from 3923 kWh exported (£5158 generated). I don have any side hustles although my eBay sales YTD are over £2k. 

I was hoping with the Powerwall and a summer on intelligent Flux to earn over £1500 next year. Perhaps I need to get an EV.

I wonder whether energy companies will be required to send a statement of earnings? 

I'll have to do the maths, but thankfully my earnings will fall into the next tax year not this one. However, I can see that I'll have to self-consume more too, so replacing the boiler with an ASHP goes up the list. And the next car will need to be an EV!