Real Solar Results

We now have solar results from the dead of winter from two systems.

Winter power in Seattle

Using the demo solar panel a typical winter day generated 153Whrs. This was generated on a 265W Grape Solar panel. This was measured by a custom device which filled a capacitor every 30 minutes and watched the rate of fill at various levels, from that it could calculate at what voltage the fill rate was fastest and thus the max wattage that could be gotten from the panel.

Using a real array the one winter day generated 1500Whrs across 9 panels or 166Whrs per panel. The panels were Astroenergy 315W ASM6612P-315. This was harvested using a MorningStar TS-MPPT-45 to a large battery bank already under load (plenty of power to absorb). While this is only the first clean day of data, it felt like a pretty typical weather day.

Because the year-long gathering of test data from the demo panel is matching the larger and production-ready version, we can extrapolate a few things about what the solar power system can be used for...

How much power we get in the winter: We can only run 62W continuous assuming perfect batteries. Thus, more like 50W only during the winter. Really, enough for maybe the freezer and the router but that's about it. This system generates just 12% of our daily power use.

How much power we get in the summer: We expect the 1.2kwhrs*9panels = 11kwhrs or 450W continuous load or practically the entire power use of our house during the summer.