Photovoltaic panels in a new build - any options?

Barack Obama

Hi. We are just about to move into our new house and it has 8 PV panels fitted facing SW.

I assumed that this would all be 'smart' and that the energy would either be sold back to the grid or stored so it could be used in the evening time. After talking to the foreman onsite, there is nothing like that in place - it's simply use it or lose it. A bit pointless when the house is empty during the daytime!!

Does anyone have any suggestions? At a minimum, I'll look into getting a washing machine and dishwasher with a timer!!

freddyuk

You can get a solar diverter into your immersion heater as that is the only way to store the energy unless you invest in a more comprehensive energy management system which can control other socket based loads.
The big story now is storing that "wasted" power in a battery bank so it can be used when you are there. It can also be charged at night (off peak) and used during the morning/evening. The solar recharges for free during the day.
Your system was installed to tick the planning box so would be there in it's most basic form. You have 2.5kwp so not a great deal. 4kwp would be a base to build on but I think your system is too small to invest any load control for a decent return unless you are in the market for a decent home energy/security management system anyway.

quentingargan

An 8 panel system will produce slightly more energy than a typical solar hot water system of 4 sq m. So if you get something like this, and wire it to your immersion, you will have solar hot water from the electricity you don't use.

I would argue that this is better than a standard thermal system because there is no pump station to fail, no antifreeze that needs to be changed, and the whole system should be maintenance free. So I would be reasonably chuffed to find this on a house that I bought. Better than the rubbish you would have bought in 2008.

Barack Obama

Tanks for the info gents, much appreciated. I'm going to get some more info from the builder about what the panels are and what the total kwp should be.

Sadly, I think the panels are actually west facing and not south west but I was out at the house yesterday and they did have direct sun on them at 11am. Not direct-on obviously!

quentingargan

Barack Obama wrote: »

Tanks for the info gents, much appreciated. I'm going to get some more info from the builder about what the panels are and what the total kwp should be.

Sadly, I think the panels are actually west facing and not south west but I was out at the house yesterday and they did have direct sun on them at 11am. Not direct-on obviously!

Typically panels are 250W each. If you're lucky, 260. If your roof is facing west at 30 degree pitch, according to SEAI you will get 1418 KwHrs from that per year. SEAI figures are generally conservative by about 10%. If you use 1/3rd of that, saving 18c per KwHr and use the other 2/3rds for water heating saving 9c on gas, then the savings would be €170 per year - half on "use it or lose it" and half on hot water.

Barack Obama

Barack Obama wrote: »

Tanks for the info gents...