Solar panels Vs battery only

[johnb2713]

you have to be VAT registered to claim back VAT.

I wasnt sure if suppliers could supply them without the VAT on the invoice?

 

[Bob Smith]

I was told the 0% VAT only applies when the system is professionally installed. So you buying the equipments and install does not qualify

 

[binky]

I wasnt sure if suppliers could supply them without the VAT on the invoice?

Nope, as per most government schemes, you have to claim it back after purchase. 3 months later usually. Hence I never discounted Vat off materials to customers, but treated the Vat as bonus money, otherwise the business would probably have collapsed waiting for the money. So solar at 5% or 0% is a bit of a myth unless you are doing the vat claim for a new build.

 

[Oldman22]

VAT on energy-saving products​

You’ll pay a rate of either 5% or 0% VAT when certain energy-saving products are installed in your home if you’re eligible.
Not all products or installations qualify for the lower rate and you cannot buy or install them yourself.
Your installer will be responsible for charging you the correct rate of VAT.
The rate you pay and your eligibility depends on whether you are in Great Britain (England, Scotland and Wales) or Northern Ireland.

If you’re in Great Britain​

You’ll pay a rate of 0% VAT on both:

• certain products supplied by your installer
• the cost of all work to install those products in your home

https://www.gov.uk/tax-on-shopping/energy-saving-products

 

[shaunuk]

You have to buy a system from a vat registered installer, which includes one of the energy saving measures. Solar is one of them. Batteries are not one of them annoyingly. But batteries and solar together including labour would be all invoiced to you at zero vat rate.

As an installer. We pay VAT on the equipment as we would everything else and then on the quarterly vat return. We are claiming for input vat but not for output vat. So the vatman owes us a refund every quarter. Which makes a nice change.

As for batteries and no solar. I unplugged our solar at the end of September and we are running on battery only as an experiment. 13kwh system. Charge at night on edf’s 5 hour cheep period. House runs on battery from 5am - midnight. If we are careful it lasts. If we are not careful, the battery gives up at some point in the evening and then we are taking from the grid at 45ppkwh which is painful. This just makes me want to increase the battery to probably 15kwh.

Will plug the solar back in in Feb probably, I suspect having solar back in the mix will negate the extra battery as we will be going into the dark evening with a higher state of charge.

As for savings. On battery only with an average usage of about 12kwh a day. We spend less than £2 a day. Which is neatly less than the governments £66 a month to all households, so we have no electricity cost at present.

Summer should be mostly solar powered, next winter is the challenge now.

 

[shaunuk]

Oh. I have come across a few people just not charging VAT on Solar pannels - supply only. I told them they have miss read the VAT situation. It’s not legal to supply only and they will be liable for the vat at a later date, but apparently the bloke down the pub knows more about it than me, I’ve only been sending VAT invoices for 20 years !

 

[Andy1733]

You have to buy a system from a vat registered installer, which includes one of the energy saving measures. Solar is one of them. Batteries are not one of them annoyingly. But batteries and solar together including labour would be all invoiced to you at zero vat rate.

As an installer. We pay VAT on the equipment as we would everything else and then on the quarterly vat return. We are claiming for input vat but not for output vat. So the vatman owes us a refund every quarter. Which makes a nice change.

As for batteries and no solar. I unplugged our solar at the end of September and we are running on battery only as an experiment. 13kwh system. Charge at night on edf’s 5 hour cheep period. House runs on battery from 5am - midnight. If we are careful it lasts. If we are not careful, the battery gives up at some point in the evening and then we are taking from the grid at 45ppkwh which is painful. This just makes me want to increase the battery to probably 15kwh.

Will plug the solar back in in Feb probably, I suspect having solar back in the mix will negate the extra battery as we will be going into the dark evening with a higher state of charge.

As for savings. On battery only with an average usage of about 12kwh a day. We spend less than £2 a day. Which is neatly less than the governments £66 a month to all households, so we have no electricity cost at present.

Summer should be mostly solar powered, next winter is the challenge now.

Thanks Shaun. I was just doing a few calculations over breakfast and I was thinking a 20kwh battery setup should be able to produce approx 7200kwh per year and of only charged at the octopus go low rate . It would cost approx £850 per year

 

[johnb2713]

As for batteries and no solar. I unplugged our solar at the end of September and we are running on battery only as an experiment. 13kwh system. Charge at night on edf’s 5 hour cheep period. House runs on battery from 5am - midnight. If we are careful it lasts. If we are not careful, the battery gives up at some point in the evening and then we are taking from the grid at 45ppkwh which is painful. This just makes me want to increase the battery to probably 15kwh.

Surely you would increase by more than 2kWh? it wqould advantageous to have a bigger store in the summer and less import from the grid for charing.

Will plug the solar back in in Feb probably, I suspect having solar back in the mix will negate the extra battery as we will be going into the dark evening with a higher state of charge.

Thats what happens on my system, yesterday we started the evening with one car 50% charged, both batteries at 100% and the hot water tank full, the net result was only 10 kWh imported last night during off peak time.

As for savings. On battery only with an average usage of about 12kwh a day. We spend less than £2 a day. Which is neatly less than the governments £66 a month to all households, so we have no electricity cost at present.

My average for January is £2.39 per day and that includes 2 x EV, heatpumps and Immersion heater.

Summer should be mostly solar powered, next winter is the challenge now.

I'm hoping for this too, I have another roof available and may well add 8 more panels this summer.

 

[Andy1733]

Btw I've ignored the std charge for both calcs

Payback for the battery's would be just under 7 years.

Spend 10k on solar panels and they would need to produce approx 8 months worth of electricity a year to match the £850 cost of the battery's. Presuming no low overnight tariff.
Though life span would prob be twice the length of the battery's.

 

[Figrol]

For 8k you can get approx 20kwh off the shelf battery's. If you add the inverter and gubbins your around 10k. If you then charge them at the cheap rates available.
1 would you have enough charge be able to fill them each day
2 would 20kwh be enough for the AVG household.
3 is it possible to charge battery's at cheap rate over night then sell access back from the battery's during the day.

I think you'll find that you'll have to pay more for your cheap electricity than you can sell it back for. Or at least there will be such a small margin in it that it would take decades to recoup your outlay cost.
In the last year we averaged 13 kwh/day usage in our house, but I do have an electric car with a 42 kwh battery, that's mostly only used on short trips and not every day. I charge my car overnight during the cheap 4 hour period and I can see that roughly, half my daily use is in this period. So the house, excluding the car and some appliances I run during the cheap hours, uses about 7 kwh per day. There are only 2 of us in the house, so if you have kids with their own computers, TVs, etc. you might use around 10 kwh per day.
I have a recently fitted a Growatt system, including pv panels and 2 x 3.3 kwh batteries. I charge the batteries up during my cheap period and they charge up at a rate of 3 kw and takes less than 2 hours to charge to 90% from 10%.

 

[Andy1733]

One major flaw with solar panels as we all know is they need sun light. (Not true obv)
In a year their are approx 8750 hours.
If we say the assumption is half these hours are night time 4375
And Where I live in Sheffield only 1485 are the avg sunlight hours per year.
then it only leaves a short time to be able to make enough electricity toake solar efficient.
Even of you maxed out the panels and inverter the amount of daylight hours doesn't change.
Options.
We add batterys and as proved over the years. The ROI is not great on battery's due to cost and lifespan.
Or
We make loads of spare leccy and sell it back to the grid to cover the costs of when we have to purchase overnight/dull days. Though since the fit payments have gone the payback is very poor.
Or
Get a combo of panels and battery's to try and cover our usage who h in the summer it's brilliant and the winter still quite expensive. It's really a tough balancing act.
Or
As above just purchase battery's and use the cheap overnight rate to charge them.
Obv problem with this is if everyone did it their wouldn't be any cheap overnight electricity ...

I'm starting to think this solar stuff is flawed

 

[johnb2713]

For 8k you can get approx 20kwh off the shelf battery's.

I think thats a very keen price, £900 per kWh seems nearer the mark.

If you add the inverter and gubbins your around 10k.

A decent 5kW inverter is around £1700

If you then charge them at the cheap rates available.
1 would you have enough charge be able to fill them each day.

That depends on your inverter choice, my 5kW Victron charges at 3.5 kW so 14kW is the max available in the 4 hour period.

2 would 20kwh be enough for the AVG household.

I would think around 12kWh would be enough for the average house. Very difficult to estimate, everyone is different and every house is different, you really need to analyse your personal use.

3 is it possible to charge battery's at cheap rate over night then sell access back from the battery's during the day.

That doesnt work, on Octopus GO for example off peak is 7.5p kWh and on export you get paid 4.5p kWh. Generate, store and use yourself is the best energy advice

 

[BorisJ]

If you go solar you get zero VAT on all of the equipment including the battery, theres 20% saving straight away.

16.7% actually but still a saving. (for every £1200 you pay £1000 saving £200. 200 is 16.7% of £1200)

 

[Andy1733]

I think thats a very keen price, £900 per kWh seems nearer the mark.
I've just purchased a 4.8kwh pylontech 5000 for £1859 Inc delivery

A decent 5kW inverter is around £1700

Would the inverter need to be a smart meter for battery only?

That depends on your inverter choice, my 5kW Victron charges at 3.5 kW so 14kW is the max available in the 4 hour period.

I've not looked into this though I'm sure their are inverters that charge at higher rates


I would think around 12kWh would be enough for the average house. Very difficult to estimate, everyone is different and every house is different, you really need to analyse your personal use.
We have 5 people in our home and our usage last year was 6397kwh.


That doesnt work, on Octopus GO for example off peak is 7.5p kWh and on export you get paid 4.5p kWh. Generate, store and use yourself is the best energy advice.
I have no idea about tariffs would octopus agile work?

 

[johnb2713]

One major flaw with solar panels as we all know is they need sun light. (Not true obv)
In a year their are approx 8750 hours.
If we say the assumption is half these hours are night time 4375
And Where I live in Sheffield only 1485 are the avg sunlight hours per year.
then it only leaves a short time to be able to make enough electricity toake solar efficient.
Even of you maxed out the panels and inverter the amount of daylight hours doesn't change.
Options.
We add batterys and as proved over the years. The ROI is not great on battery's due to cost and lifespan.
Or
We make loads of spare leccy and sell it back to the grid to cover the costs of when we have to purchase overnight/dull days. Though since the fit payments have gone the payback is very poor.
Or
Get a combo of panels and battery's to try and cover our usage who h in the summer it's brilliant and the winter still quite expensive. It's really a tough balancing act.
Or
As above just purchase battery's and use the cheap overnight rate to charge them.
Obv problem with this is if everyone did it their wouldn't be any cheap overnight electricity ...

I'm starting to think this solar stuff is flawed

It's very difficult to predict savings etc. What I can tell you is my experience with actual figures.

My system (6kW Solar PV, 7 kW Battery) was installed at the end of April 2022. Looking at the summer figures May - Sep.

2021 May - Sep Peak Electricity Used 6332 kWh
2022 May - Sep Peak Electricity Used 292 kWh

Saving 6040 kWh - 1208 kWh per month at the current rate £352.73 per month.

2021 Oct - Dec Peak Electricity Used 2090
2022 Oct - Dec Peak Electricity Used 638

Saving 1452 kWh - 484 kWh per month at the current rate £141.32 per month

There are more savings than illustrated here, we didnt use the gas boiler in the summer at all, hot water now heated via the immersion heater. Surprisingly, off peak consumption is also reduced between 2021 and 2022.

My average saving over the year more than covers the repayments for the loan I took out to install it all.

 

[Andy1733]

I think thats a very keen price, £900 per kWh seems nearer the mark.


A decent 5kW inverter is around £1700


That depends on your inverter choice, my 5kW Victron charges at 3.5 kW so 14kW is the max available in the 4 hour period.


I would think around 12kWh would be enough for the average house. Very difficult to estimate, everyone is different and every house is different, you really need to analyse your personal use.


That doesnt work, on Octopus GO for example off peak is 7.5p kWh and on export you get paid 4.5p kWh. Generate, store and use yourself is the best energy advice

Pylontech 5000. Are around £1850 they are 4.8kwh.

Inverters. Do they need to be smart meters when you don't have solar panels?

I've hear mentioned on this forum you can get inverters to charge at higher rates. Tbh I think mine is 2.5kwh

We have 5 adult on our house and are quite large consumers. Koi pond ect. W0kwh would be about what I use

What does octopus agile or the recent smart tariff offer regards pay ack. Isn't one of the paying back large amounts at peak times

 

[johnb2713]

Pylontech 5000. Are around £1850 they are 4.8kwh.

That seems way below average, good if you can get them at that price.

Inverters. Do they need to be smart meters when you don't have solar panels?

Smart meters are nothing to do with inverters, it doesnt matter what type of meter you have.

I've hear mentioned on this forum you can get inverters to charge at higher rates. Tbh I think mine is 2.5kwh

The hybrid inverters will charge up to their specified rate, ditto solar inverters with MPPT chargers.

We have 5 adult on our house and are quite large consumers. Koi pond ect. W0kwh would be about what I use

To be fair pumps dont take much by way of power to operate, 20kWh per day is a fair amount of power, saving are there to be had. Utilita have a 5.33p off peak rate, if you used 20 kWh per day your electricity bill would be £1.06 per day (theres no standing charge) or £32.42 per month compared to £255 per month for a standard tariff. Under 4 years to break even assuming your £10k to get the equipment etc.

What does octopus agile or the recent smart tariff offer regards pay ack. Isn't one of the paying back large amounts at peak times

There are times where the export payment is really good, there are however lots of other times when import costs are high and export costs are low. You literally have to be on duty to drive your system as required. I use Octopus GO and I know from 00:30 to 04:30 I have 7.5p kWh and from 04:30 to 00:30 I have 29.2p kWh, I just make sure I buy all of my power between 00:30 and 04:30. I have looked at agile many times and I just dont see where I could gain over GO.

 

[Andy1733]

You must have a fixed rate on octopus go cos my chargers are 12p and 40p high/low rates.

The bot about smart meters. I had a mind melt. I was going to say smart inverters. IE hybrid inverters


Link to the battery's. Tbh they look like they have come down in price though they charge £80 delivery

https://www.itstechnologies.shop/products/pylontech-us5000-4-8kwh-95-d-o-d-battery-storage

 

[johnb2713]

You must have a fixed rate on octopus go cos my chargers are 12p and 40p high/low rates.

Tariff expires at the end of March when it becomes 12p and 36p, I will be moving to utlitita at that point on 5.33p.

The bot about smart meters. I had a mind melt. I was going to say smart inverters. IE hybrid inverters

No problem, theyre not smart in any way just have a built in battery charger

Link to the battery's. Tbh they look like they have come down in price though they charge £80 delivery

https://www.itstechnologies.shop/products/pylontech-us5000-4-8kwh-95-d-o-d-battery-storage

If youre getting more than one, rent a van and go and collect, price is now £1653 BTW.

 

[Andy1733]

Tariff expires at the end of March when it becomes 12p and 36p, I will be moving to utlitita at that point on 5.33p.


No problem, theyre not smart in any way just have a built in battery charger


If youre getting more than one, rent a van and go and collect, price is now £1653 BTW.

I know. Decent Price drop from when I bought them and also they give a bigger discount if you buy more. 5 of these gives you 24kw at 8200 ish price