# Adding on a solar panel?

Now things are clearer

He’s got 600w, not 300w, but there is no way that powers that contraption alone.

He’s got car batteries in there, which the panels charge. He also has pedals which " help to power him down the highway"

The details are all a bit muddy, if you follow the link from the article (http://www.cbc.ca/news/canada/thunder-bay/solar-bike-turning-heads-in-thunder-bay-1.1133385) you see the non-trailered version which he claims is around 18 Kg! lol. On that one he has three rigid 100W panels, They weigh 8 Kilos each. Trust me, I know. So that’s 24 Kilos in panels before you’ve even allowed for the trike - whose wheels are probably 5 or 6Kg each…

Then there are the batteries… If he’s using car batteries it’s a huge weight, so I would hope he’s using Lipos or similar, though he refers to a 48v system which is coincidentally the exact voltage of 4 car batteries in series.

On his trailered versiojn he’s using 6 thin panels. They weigh much less, like 2 Kg each. But his trailer is heavy duty.

He’s aldo got the panels angled at one side so he’s grand when cycling with the sun to his side, but he’s snookered when he turns a corner and the sun is behind / in front of him.

The reality is that the solar panels charge his batteries, which helps him pedal. He stops to eat/rest etc - at which time he’s getting good solar energy put into the batteries. When he goes down hill he’s also charging the batteries.

600W is not enough however, to reliably power that thing. Take a look at my numbers again. it doesn’t stack up.

The solar is , as he has stated, “helping him”.

Also remember that 600watts is ideal conditions. I can tell you for a fact that a 100W panel maxes at around 85 watts after real world losses, and that is when it’s pointed directly at unobstructed sun.

So, I assume at 85% max efficiency he might achieve 510w of power in direct sun… now, if ‘‘remove’’ the panels on the ‘‘shade side of the sun/trailer’’ from total power received from sun… Then we might divide this number by two or so?

Perhaps by 1.7 would be better… as there is still some light flowing in into the panels on the shade’s side…

So now we get about: 510 / 1.7 = 300w of power…

I assume there could be some other… minor losses and ‘‘not ideal sunlight’’… so during somewhat cloudy not so sunny day… he should still get about 100-200w of power, right?

I know… this is not direct solar energy… but I think we will get there some day… when the panels get more efficient or some other new tech (like lenses for panels) become more available/popular…

Thanks ALL

Are solar panels affected by rain? How solar panel working changes in different seasons?