I have existing solar panels and economy 7 heating - is it worth getting batteries?

smart_taunton_bloke

Hi Everyone, 

I've been through the other threads but can't seem to find anyone in a similar situation. 

We had 14 solar panels fitted in 2020. 

We have economy 7 heating. 

Current daytime rates are 44p, off-peak is 16p.

We only have electricity and no smart meter. I have been trying to track the amount we use and I think it's about 7000kw a year, split 50/50 between day-times and off-peak rates. 

I just cannot figure out how much we would benefit from using solar to charge batteries in the summer, and off-time electricity to charge them in the winter. 

I've had a quote of £6.800 to install an inverter and 2 x 3.3kw batteries but do not know how to work out if they will pay themselves back. I've read in other threads that we should not really worry about payback but at nearly £7k it's not a small outlay. 

Can anyone help me work this out or are/have been in a similar situation? Thank you. 

markin

Why is the daytime so high?

Updating some heaters to modern high heat storage heaters, Or even an Air to Air (A/C) heatpump that are great for the shoulder months going into and out of winter, May be better and faster return investment. 

The first step i think is to get a smart meter, and move to octopus to get the best seg from the solar.


Some threads for you to read.

https://forums.moneysavingexpert.com/discussion/6240076/i-bought-a-heat-pump

https://forums.moneysavingexpert.com/discussion/6385038/solar-battery-yes-no

Astria

How much solar did you generate over the last 2 years on average?

How much of this solar is self-use, and how much did you export to the grid?

It's impossible to know unless you have the answer to these.

It might be better to swap supplier than install batteries depending on your usage and generation.

powerful_Rogue

smart_taunton_bloke said:

Hi Everyone, 

I've been through the other threads but can't seem to find anyone in a similar situation. 

We had 14 solar panels fitted in 2020. 

We have economy 7 heating. 

Current daytime rates are 44p, off-peak is 16p.

We only have electricity and no smart meter. I have been trying to track the amount we use and I think it's about 7000kw a year, split 50/50 between day-times and off-peak rates. 

I just cannot figure out how much we would benefit from using solar to charge batteries in the summer, and off-time electricity to charge them in the winter. 

I've had a quote of £6.800 to install an inverter and 2 x 3.3kw batteries but do not know how to work out if they will pay themselves back. I've read in other threads that we should not really worry about payback but at nearly £7k it's not a small outlay. 

Can anyone help me work this out or are/have been in a similar situation? Thank you. 

Seems rather expensive. I paid £2400 for an additional 6.5kWh battery when I had my install done in October.

Just had a quick look online to see how much an inverter would be, and this company offer a 6.5 kWh battery, inverter and installation for £4761.

https://lr-renewables.co.uk/product/growatt-6-5kw-battery-storage-bundle-installation-included/

carly

Seems expensive to me too...... recently  had a 9.5 kWh battery and inverter fitted for 6000.  West Midlands area.

Petriix

If you don’t have a smart meter, how are you paid for your exports? I thought the FIT scheme ended in 2019.

Without smart meter data it's basically guesswork as to whether a battery makes sense, although (at current prices) you'd normally need to be a very high user for the sums to add up favourably. 

macman

Petriix said:

If you don’t have a smart meter, how are you paid for your exports? I thought the FIT scheme ended in 2019.

Without smart meter data it's basically guesswork as to whether a battery makes sense, although (at current prices) you'd normally need to be a very high user for the sums to add up favourably. 

FIT ended for new sign-ups. It continues for existing customers, who are paid based on a deemed 50% export of their total generation.

smart_taunton_bloke

markin said:

Why is the daytime so high?

Updating some heaters to modern high heat storage heaters, Or even an Air to Air (A/C) heatpump that are great for the shoulder months going into and out of winter, May be better and faster return investment. 

The first step i think is to get a smart meter, and move to octopus to get the best seg from the solar.


Some threads for you to read.

https://forums.moneysavingexpert.com/discussion/6240076/i-bought-a-heat-pump

https://forums.moneysavingexpert.com/discussion/6385038/solar-battery-yes-no

Thanks for your reply.

We're on UWs standard ecom 7 tariff at the moment until we decide what to do.

We have Dimplex Quantum heaters so are quite new. They work well when you know it's cold. But they are a pain when you get a hot daytime in the spring, but a cold morning or evening but you haven't stored the heat.- Again that's another reason why batteries might be better and move away from storage heaters so we can use heat when we need it. And in the winter use the off peak battery storage to run electric oils heaters in the daytime.  

We have a bedroom where the smart meter would need to go, and I have heard they are not good if you are sleeping in the same room, that is why we haven't got one. 

smart_taunton_bloke

Astria said:

How much solar did you generate over the last 2 years on average?

How much of this solar is self-use, and how much did you export to the grid?

It's impossible to know unless you have the answer to these.

It might be better to swap supplier than install batteries depending on your usage and generation.

Thank you - we don't know - we don't have a smart meter. I did a reading a couple of days ago when it wasn't sunny and it was about 7k output - do think that seems correct for January? 

So I don't know the answer to these questions, but I am reluctant to have a smart meter because we currently use the room it would be in as a bedroom. 

smart_taunton_bloke

powerful_Rogue said:

Seems rather expensive. I paid £2400 for an additional 6.5kWh battery when I had my install done in October.

Just had a quick look online to see how much an inverter would be, and this company offer a 6.5 kWh battery, inverter and installation for £4761.

Thank you. Yes that is a much better price! I will get in contact with them. I wonder why they are so much cheaper? I have emailed them. thank again. 

smart_taunton_bloke

carly said:

Seems expensive to me too...... recently  had a 9.5 kWh battery and inverter fitted for 6000.  West Midlands area.

Thank you - I am going to get another quote. The guy mentioend about a bigger battery, but I could upgrade later if I wanted.