This blog explains how I keep bees. It works for me, it might not work for you. Use my methods at your own risk. Always wear protective clothing and use a smoker when working bees.

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Friday, June 28, 2019

Solar Update - Shading

I have been asked quite a few times how our solar system is working out. I was planning on doing a video of the solar system after one year of use. That would be around mid October when it was turned on.
 For a refresher, our solar system is 16.5 kw. There are 50 - 330 watt panels.
 18 panels on the garage and 32 panels on the pole barn.
As of today, our system has cranked out approximately 10 megawatts of electricity so far. That is 10,000 kilowatts since October. A typical house in America uses about 7,500 kilowatts per year. We use more power than the average home because of our beekeeping business.
 So we still have another 3 -1/2 months left before a year is up. We should probably add another 5-6 mega watts in the next 3-1/2 months. So I would have to say, so far, the solar system has been a big success. The last three electric bills were March, we owed $27.00 for gas and electric, April, we had a $137.00 credit, May we had a $87.00 credit. Xcel writes us a check right away for any credit.
 But what I wanted to comment on today was shading of solar panels. If you are considering solar, shading should be a consideration before making a move.
 The panels on our pole barn see full sun most of the day. The panels on the garage get shaded later in the afternoon from a big Ash tree. My wife and I value the shade tree and are not going to remove it. But, shading on solar panels can be an issue. Even small shading has an effect. Here are some pics on the shading and what it did to the solar panels. Now don't get me wrong, the panels do put out very well when the sun is on them, but the panels get shaded at about 4:30 every day and there are much lower solar gain because of it.
Right now the shade is creeping on to the roof. The roof solar system is putting out about 4000 watts of power

Now about twenty minutes later there is some shade on a few panels. The power output now is about 1600 watts.

Now the solar panels are basically fully shaded. They are putting out about 300 watts.
 I went back and looked at my solar panels on the roof of my pole barn, still in full sun, they were putting out about 4500 watts at this same time as the shaded panels were putting out 300 watts.
 Shading of panels can have a negative outcome on solar panels. Shading can come from anything, a power pole, roof vent, flag pole etc. While some times slight shading doesn't affect the panels much, it is best to avoid it if possible.