Will the real Slim Shady please stand up

[CPT Davenport]

Just returned from a lake trip in the Tahoe NF. Camped for 5 days without moving the rig. Our site was under the filtered sunlight of pines and cedars. Between that and a couple cloudy days (actually had a bit of rain), my 206ah lithium was down to 32%. I tried to move my aux 135w panel into as much sun as I could but the power generated from my 170w Renogy flexible panel was minimal. It seems like the slightest bit of shading cuts its intake to next to nothin.

Any suggestions for a flexible, light weight panel that is not so effected by the shade?

All that said, it was nice to still have full power in the rig, even with only 32% battery capacity.

 

[ckent323]

The performance of all solar panels are significantly reduced by shade.

Here is a fairly straightforward explanation (see link I borrowed it from for more info)

Solar panels are made up of individual solar photovoltaic (PV) cells, which are thin slices of silicon that typically measure 6 square inches. Each solar cell converts sunlight into electricity in what’s called the photovoltaic effect. Multiple solar cells are assembled to form a single rectangular shaped panel or module. Multiple panels are then assembled into an array to provide the solar power.

All of the cells in the panel work together as a single system; each cell is a link in the chain. If one cell is shaded, its power output is reduced and the entire panel’s efficiency drops. Because all the cells are interconnected and work together, the maximum current the whole module can achieve will be no greater than that single shaded cell. Studies have shown that shading just one cell in a panel can reduce the solar power output of the entire panel by a whopping 50-80%.

Avoid Solar Panel Shading: How To Minimize Its Impact

Solar panel shading can have a negative impact on solar energy production. Learn why it should be avoided and how to minimize its effect.

www.velosolar.com

 

[CPT Davenport]

Thanks for that breakdown. I’ve been researching panels with bypass diodes or individual micro inverters for each cell. It seems like there could be some options that address the problem. For now I think my easiest solution would be to get a way longer cable for my aux (out the back port) panel and stretch out to the sun when possible. As the article mentions, this is a separate “racetrack” and is not effected by shade on the main panel.