Power Production Update

At the end of November we had a surprising 400-some KWh in credits on our meter. After 28 days of snow and clouds, I suspected we would have burned that up by far. When I checked the meter 12/28, I saw we had finally bought 122 net KWh from the grid. I never thought we could get this far into winter before dipping into the grid. The gridtie system has performed beyond expectations here in the West Virginia hills and hollers. Can't wait to see when we get back into credit territory.

Return of the Sun, Eclipse of the Moon.

Ever since near the end of November to present, our weather has been unusually cold, snowy, and cloudy. It's the kind of weather you would more expect in January. Needless to say, it really knocked a hole in our PV production. Our predicted harvest was for 216 KWh, the lowest month of the year. So far, we have only captured 96 KWh and it is the 20th already. This is where the climate averages play in. Even though this month is bad, last month was well above average. That's why you can't get freaked out over unusual circumstances with solar, it all works out in the long run.
One thing to celebrate is the Winter Solstice on the 21st. It is symbolic mostly, however it does mean that the sun will be rising ever higher and the days become longer. That's about all we can reinforce ourselves with as we enter January and the bottom of winter. By March, we are predicted to produce 435 KWh, twice as much as December. I think that's plenty to look forward to.
As an interesting note, around 3am tomorrow morning, there will be a total lunar eclipse. It will be the first one to fall on the Solstice in over 400 years and we can all witness it as long as it's not... CLOUDY.

Shadow Study

One thing you can do on snowy days is to explore the capabilities of your computer. I regularly use Google Earth to study PV site for potential customers. This time I decided to model our proposed shop PV array using Google SketchUp (free, google it) The sketchup program can use Google Earth data for shadows and geophysical features. There's a control where you can set anytime of the day, any day of the year, to see how the sun's shadows affect your array. Even nearby mountains will cast their shadows accurately.
I wanted to confirm my row spacing for maximum module density without interference. It takes awhile to get a handle on modeling in sketchup, but its time well spent. I will use this tool to prove the design is good for a grant we are pursuing and see how roof angles and protrusions may influence some future complex new install.

Winding Down

After finishing the job described on the previous post, I thought there would be a quiet period while winter ramped up. To our surprise we started a job on a new home site by setting poles for a top of pole PV installation. We'll try to get all the conduit laid while the builder is there with excavation equipment. At some point he'll have to shut down during any severe weather. We'll pick it up again when the weather returns to bearable.
It's been unusually cold and cloudy for the past week and we're using our last couple hundred KWh's in credit on our meter. To our further surprise it looks promising for another PV job where the owner wants to spend the money this year for tax purposes. We'll work on that one as the weather opportunities arise.
In the photos above you can see the pole fabrication in progress. I want to thank Lola Alderman for helping and doing a fine job on finishing. By the way, that's my new forklift I got to unload trucks delivering pallets of PV modules. In fact, its only new to me, it has some hours on it and I had to rebuild some linkages and fit chains to the tires. We couldn't afford a forklift that didn't need fiddling, so I'm happy to do it. It runs well and we might even paint it.
The pic of the PV array is the one at our house after days of snow showers. The deep blue sky is a wonderful sight. I didn't brush off the snow so I could see how it melts and slips off with a little sunshine. It took 4 hours to clear itself that sunny morning.