Combined community and household PV and battery storage

[Stones]

I'm involved with a local project that will be a mix of community commercial premises and housing for rent.  One of the things we are thinking about is a semi combined / community PV and battery storage system - fitting as much PV as we can to the commercial buildings, and cascading surplus generation first to battery storage for the commercial buildings, then when they are charged, to batteries in the rental houses. The rental houses would have their own PV fitted, which would divert excess generation into a household battery and potentially a DHW cylinder.   Each property, be it the commercial buildings, or the domestic properties would need to remain islands for billing purposes. 

 

Is this possible? - I can't see why not

Would the domestic properties need two batteries - one for excess feed from the commercial building, and one fed from their own array?

 

Has anyone experience of setting up or been involved in anything like this? 

 

 

[SteamyTea]

Technically possibly.

Legally it is a mine field.

Two things spring to mind.

VAT and non payers.

Nearly every community energy company I have heard about fails, and not many people have working shared CHP units, or shared biomass boilers.

 

Just stick as much PV on everything.

 

https://www.gov.uk/guidance/community-energy

Edited February 13, 2023 by SteamyTea

[Stones]

To clarify, there is no intention to charge the domestic properties for any excess diverted from the commercial array. Clearly there would have to be legal agreement on who was responsible for the battery and tech that would enable this.  In this case it would be the community company that runs the commercial business, as they would also be the landlord of the rented houses.  Absolutely take the point if trying to sell to households for the reasons you have listed.

[SteamyTea]

1 minute ago, Stones said:

To clarify, there is no intention to charge the domestic properties for any excess diverted from the commercial array

So 1 EV for the first lucky owner.

 

You have to charge, or at least limit usage or it just encourages excess usage.

[TW9]

That's a recipe for neighbourhood discontent. There will be arguments about who is using more than their fair share.

[Dillsue]

10 hours ago, Stones said:

fitting as much PV as we can to the commercial buildings, and cascading surplus generation first to battery storage for the commercial buildings, then when they are charged, to batteries in the rental houses. The rental houses would have their own PV fitted, which would divert excess generation into a household battery and potentially a DHW cylinder.   Each property, be it the commercial buildings, or the domestic properties would need to remain islands for billing purposes. 

 

Is this possible?

I'd imagine distributing the surplus evenly to the rental houses would be technically quite complex, maybe bespoke and likely costly. Given that it's free electricity being dished out which is more or less the same as giving cash away, I'd imagine it could cause some friction if it wasn't shared evenly.

[SteamyTea]

7 minutes ago, Dillsue said:

more or less the same as giving cash away

Yes.

So better off selling the excess to the highest bidder and giving out a cheque at Christmas to everyone.