Zero Energy Home: It Sure is Hot

It sure is hot!...outside, that is. Texas is experiencing a long, hot summer. Well, that's normal for Texas, but what we're experiencing is unusual, with long strings of 100+ temperatures, and almost no rain. Of course, the lack of rain means that our solar panels get nearly a full dose of sunlight every day.

I've noticed that there is some morning shading along the top row of our panels (our large oak tree at the side of the house hangs over them). Some thumbnail calculations suggest that we're losing about 3kWh per day, which is about 10% of our power generation. We're fortunate that it only shades the solar panels during the peak of the summer, when the sun is almost directly overhead.

Solar power has come quite a way – it wasn't that long ago that shading over some of the panels would have seriously impacted the generating capacity of the entire system. But with new technology (such as micro-inverters), we don't have to worry about shading nearly as much.

At this point our electric bill is a competition between the heat of summer and the summer sun. They often go together, but with the unusually hot summer, the heat would be slightly ahead – except that we built up a substantial credit in the months leading up to this hot, hot summer. Our “bill” for June/July was $8.66 (correct this time!). With our outstanding credit of about $175, it'll take a few more months of unusual weather before we actually have to pay anything.

We've been in our new house just over a year (although the solar went in a few months later, so we don't have a full year of solar history, yet). One of the best parts of living here is getting the electric bill each month, because it shows that our house is likely to be a net energy producer over the course of a year. It's almost like Christmas – just a lot hotter.