Sunday, January 14, 2018

Rethinking Solar

Readers of the blog will recall that I decided against a permanent solar panel install on the roof of the Mini like I had on the Tank due mostly to me not wanting to drill into the roof of the Mini fearful of future water damage, the bane of all RV owners.  Instead, I went with a 2 panel 200 watt "Solar Suitcase" from Renogy, a California-based solar company which tends to give a better solar "yield" than panels that lie flat because the suitcase can be aimed at the sun at the most beneficial angle.

The 200 watt Renogy Solar Suitcase in action.

Rather than use lead-acid batteries like I did in the Tank I went with lithium-ion batteries that have the advantage of being much lighter albeit at a significantly higher cost.

The Mini's lithium-ion solar generator.  345 watt hours of goodness.

Initially, the system worked great.  The Solar Suitcase would quickly charge the solar generator and keep it charged all day during heavy usage.  In fact the Solar Suitcase was TOO efficient as after the 100% charged meter showed up the generator's internal fan would kick in, indicating the lithium-ion battery was getting too warm from charging.  (Ask Samsung Corp. if lithium-ion batteries can overheat and catch fire.)  Re-reading the generator's manual I discovered that the manufacturer said not to charge the generator with more than 100 watts of solar...oooops!  As a partial fix during really sunny days I'd cover one of the Solar Suitcase's two 100 watt panels, effectively reducing it's output to the desired 100 watts.

Covering a panel to reduce the solar charge to the generator.

I decided to use the suitcase to charge the Mini's 12 volt lead-acid battery and purchased a new Renogy 100 watt panel that I'll use to charge the generator.  I'll still have the suitcase available to charge the generator on cloudy days when efficiency is reduced due to lack of sun if needed.

The stand-alone 100 watt Renogy panel for the generator.

This week is the big move to a two week boondock in the desert outside Quartzsite so I'll get a great chance to break-in the new solar setup and I'll be sure to update how it's working.

Thanks for reading!