Torqeedo solar panel

[John P Lebens]

I was visiting our local used and new boat parts store yesterday to inquire about Torqeedo motors. The owner, Kim, reported that a customer had used Torqeedo's portable solar charger during a trip to Barkley Sound this past summer. She said he was able to cruise for three hours with no net loss in battery charge while using this panel. Kim said this was the first solar charging product she has found that actually works as advertised and appears to be durable enough for a marine environment.

http://www.youtube.com/watch?v=2PtbE9m7nn8

Here's a link to a U-Tube video of the devise in operation.

[McMike]

I guess solar is a viable solution after all . . . Very cool.

[John P Lebens]

Between the motor and the panel, we are looking at just under $3000, so this is not cheap. Then again, is any high quality product from Germany cheap?

[McMike]

I would assume the panel can be used for other gear as well as charging batteries, no?

[John P Lebens]

I think it is designed for 24 volts and appears to have a proprietary plug, so I don't know how usable it would be for other applications.

[AstoriaDave]

I was visiting our local used and new boat parts store yesterday to inquire about Torqeedo motors. The owner, Kim, reported that a customer had used Torqeedo's portable solar charger during a trip to Barkley Sound this past summer. She said he was able to cruise for three hours with no net loss in battery charge while using this panel.

Third hand hearsay notwithstanding, that is very interesting. Any idea what the conditions were, what the craft was, which motor was used (prop also) and how often during the three hours the motor was used?

Sea kayaking buddies of mine use similar panels routinely to recharge their batteries for handheld electronics: VHF, GPS, cameras, etc. And, the panels are very good if orientation to the sun is maintained. A terrific use for solar.

[David Cockey]

The panel is rated at 62 watts, presumably in bright sun without shadows. The rated power input of the 401 Torqeedo, their smallest unit, is 400 watts, so 62 watts corresponds to 15.5% of max power. For the larger motors the fraction of max power available running from the solar panel only would be smaller. Run at a higher speed which requires power from the battery and the battery will be drained.

[willmarsh3]

I noticed in the youtube video that some of the panels in the fold out pack were not oriented well to the sun. That tells me that they are wired in parallel. This is a good thing. The video states that he hooks up an "SAD" connector. I suppose if you wanted longer cruising range then hook up two such solar panel packs in parallel with a 2 to 1 combiner that you built from parts. It would be interesting to see if Torqueedo comes out with such an accessory.

[St.J]

he was able to cruise for three hours with no net loss in battery charge while using this panel.

That's remarkable.

Thanks for the link John

[genglandoh]

Thanks for the Post.

I have a Kingfisher20, British Twin Keel sailboat, is weights about 2900 Lbs and I use an electric trolling motor as my aux.
An Electronic motor works well for me because I sail in lake Erie with no tides or currents and I only use the motor for around the boat ramp area.

So you post is very interesting I will be looking at a solar panel this year to keep the battery charged.

[Chip-skiff]

This sort of thin-film PV panel is pretty amazing— there are fold-up arrays such as the one shown and stick-on arrays that can be applied to curved surfaces.

There was a researcher on NPR Science Friday who's working on conductive powder that can be incorporated into yarns— it's possible that a dodger or awning, perhaps even a sail, might be used to collect solar energy.

http://www.sciencefriday.com/program/archives/201101071

[ahp]

That fold out solar panel looked to be about 10 square feet, or more. Sunlight, if falling directly onto a surface is 75 watts/ sq. ft. His panel should intercept at least 750 watts if oriented for optimum interception, but it isn't so you must multiply by the cosine of the zenith angle of the sun I am being picky.

He claims that the panel generates 62 watts. The best efficiency reported recently for solar cells is about 20%, but 10% would be more common. Hence his claim of 62 watts sounds about right. 746 watts is one hp, then 62 watts is .084 hp. Would that power propel that boat at 1.5 to 2.0 mph? The boat looks light, so yes probably. I noticed that it left in burst of speed but it didn't last.

[John P Lebens]

From what I have seen, these electric motors trade range for speed. I suspect the guy who went three hours was going pretty slow and not dealing with currents or wind.