I had PV installed in mid-August, and at the time the installer said a battery wasn’t worth it because we’re only 2.56kWp (yeh, tiny I know!). And I think he was right, since that was the Tesla Powerwall that they sold. There’s no way we would have made the money back on that.
But now I have some data from OEM, I see that We generate basically spot on the amount we use. Sure, we’re heading into winter so that will start to drop off. But still, it’s encouraging. Of course we only end up “using” roughly half of it. Some gets diverted to the HWT, but it still pains me a little that we’re not making full use of the electricity.
Some data. If I look at the entire time I’ve had OEM, which is from around August 25th 2016, I have this:
Total house usage: 325kWh
Diverted to immersion: 131kWh
Does anyone have any experience with batteries for solar PV and how much you need to be generating above your house’s base load to make it worthwhile? I’m an investor in Powervault and considered chatting to them about getting one of their units which are a lot cheaper than the Tesla, but obviously aren’t as good.
Or am I just being mad in thinking I should invest in a battery right now?