Solar PV, 3 weeks in

Our solar panels have now been in for exactly 3 weeks, and in that time we’ve generated 140 kWh of electricity.

It’s been a fairly sunny three weeks, but the panels are generating to specification.  If you want to know more, please contact me.

In order to see what is going on, I also purchased an energy monitor, which I’m developing some software for. The monitor measures the current every 6 seconds; measuring what the house is consuming, what the solar PV is generating, and aggregates the data. You can see our usage since I bought the monitor above. I’ve also got sensors on several appliances around the house as well as the under-floor heating, so more measurements should be coming as we enter the heating season in October.

The green dots at the top are the total kWh used by the house each day, and the yellow dots at the bottom are what was generated by the solar panels.   The bar graph is the consumption for two hour periods each day, the the sample immediately after the date line being from 1-3 AM.  The values above 0 are consumption, and the values below are generation from the solar panels.

The monitored values are currently inaccurate, as you’ll notice the generation in the middle of the night.  This is because the current measurement does not correct for power factor, but that is alas another blog post.

The good news though?  Over the last 3 weeks we’ve used almost no net power during daylight hours, averaging just 1.5 kWh.