Solar Panels continued

The solar panels should theoretically put out about 3800 watts maximum when the sun is overhead and there is no shading. Unfortunately there are 2 trees that shade them until the sun reaches about 35 degrees in the sky, so we have not had a full days production yet. The maximum instantaneous power we have gotten so far has been about 2400 watts, because just as the sun is getting highest in the sky ( 24 degrees! ), the trees start to shade them.
We actually hit max production for the day a little before 10:30AM and then again after about 2pm – so what should be the best time of day is blocked out.

This chart shows how high the sun gets in the sky across the year.
We have to wait until mid march before we will have a day of full sun with no shading. Do we cut down the trees? Only time will tell.
It also shows that the maximum possible number of sun hours ( where the sun is at least 15 degrees above the horizon ) in february is about 6, and in june it will be close to 12. In march we will have about 6 hours of the sun above 30 degrees and in june it will be about 9 hours.

Here is the production we have gotten so far:

As you can see we have only had 3 or 4 days so far with minimal clouds.
Every day as the sun gets higher the best day will improve.
I am hoping that by june most days are sunny and those sunny days will produce 30+ kWh.

More to come.


2 responses to “Solar Panels continued

  1. I doubt cutting trees would be useful, even ignoring the significant negative ecological and aesthetic effect that doing so would have. The trees may well not even block the sun in the months when the sun is higher, but if they do block then sun, then those are the months when you need shade more than electricity. I mean, you need both (’cause the a/c runs on electricity), but you’re going to get more solar heat gain from the unblocked sun than you can remove with your heat pump via the electricity generated by the solar panels.

    In the winter, the solar gain would be useful, granted. But I doubt in the long run the net gain would be positive.

  2. How does your energy production compare to your energy used in driving? It looks like even in these winter months, you must be close to meeting your commute needs.

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