PV Metering

prydien · Aug 15, 2013

Hello
I'M not very clued up on PV supplies and I don't get involved in it.
So perhaps if there are any PV experts someone could help me out with this one.
A customer of mine is a landlord who owns several office units.
Each office unit has its own sub meter which he uses to invoice his tenants for their electricity usage.
He has just had a huge PV array installed and this is of course slowing the main meter at the supply head.
Am I correct in assuming that all the sub metering on site will also be slowed?
He wants to be able to carry on invoicing his tenants for their actual electricity consumption while he benefits from lower electricity bills.
He has enquired about having a FIT meter installed but says that the cost of that is prohibitive.
Thanks

TedM · Aug 15, 2013

It will depend upon the exact wiring details of how the PV generation has been connected, but it would be unusual for the sub-metering to be affected. These meters should continue to measure the total consumption for each tenant, some of which will come from the new PV system and any balance from the grid as before and the landlords import meter should run at a lower figure.

Is the system not registered for FiTs? By 'huge' I would presume that you mean bigger than 30kW? This would mean he needs a FiT export meter to get paid the export value of the generation, and this would need to be a half-hourly meter which can be expensive as they require an annual O&M contract. Shopping around can help to find a better price than that first offered.

yellowvanman · Aug 15, 2013

If the PV is feeding into the installation between the main DNO meter and the tenants meters then tenants will see no benefit in the PV and landlord will have smaller electricity bills but the tenants will still be paying the same.

prydien · Aug 16, 2013

Thanks guys. There are three separate 50Kw arrays connected to three separate supply heads. There are no FiT meters. He reckons that anything he feeds into the grid will be swallowed by the O&M contract costs.

TedM · Aug 16, 2013

If these are not registered for FiTs (and without the export element they would only need total generation meters with no O&M cost) then he is throwing away at least 11.1p per kWh generated (could be more if they qualify as 3 separate sites) which is possibly £15k a year. Registering for export is not compulsory.

I find it hard to believe that any PV installer would fail to put total generation meters in place. Retrofitting these, if they are not already there, would not cost much - a few hundred at most.