New fully solar electric bike!

[Grelinette]

Hello,

Have you heard this announcement?

This blog talks about it: http://www.isabelleetlevelo.fr/2016/02/24/le-velo-a-assistance-solaire-sans-prise-ni-tete/

The efficiency of the photovoltaic cells used would be 20 times higher than traditional pv cells, and their batteries would have a longer lifespan. There would therefore be 2 announcements of innovations: best pv cells and best battery !

It was developed by the company Solar Application Lab

Should we believe it?

Or is it an announcement effect for the commercial launch of this new electric bike, planned for 2017, in a market which is now very competitive ...


PS: just like the scandal of the performance of gasoline cars (consumption, autonomy, pollution), it would be interesting to make a good comparative study between the technical characteristics announced by the manufacturers and the sellers of VAE, and the real performances in normal use (autonomy, speed), as well as the duration of the batteries ...

[dede2002]

20 times more efficiency, therefore 2000W per square meter! It will be necessary to increase the power of the sun ...

[Grelinette]

It seemed to me that the figures announced were outside accepted values ​​...

In addition, when we see the surface of the photovoltaic panels fixed on the spokes of the bicycle wheel (if the image is indeed that of the VAE in question), it really is not heavy!



It is perhaps an assistance only for the descents!

[Grelinette]

Finally, it is interesting this type of commercial announcement because it is a good opportunity to recall the basic data of solar energy ... (subject which surely had to be largely approached on econology)

The maximum PV yield found on the net is 25% (yield given by the manufacturer, but surely very optimistic ...)
Optimal sunshine with 90 ° radiation produces 340 W per m² maximum! ... (correct me if I made mistakes)
(To this we must add the angle of the sun's rays with the PV vertically attached to the wheel ... and perhaps the fact that their rotation must influence their efficiency! ...)

... and therefore to take the problem upside down:

a standard pedelec has an engine with a power of 250 W (maximum legal in France), a 36 V, 10 A battery, for a given range of around 50 km.

To have a correct recharge of the battery only with the sun, and taking into account the data cited above,
what surface of on-board PV (let's take 25% efficiency) would it take?
(I let the specialists do the calculation ).

[dede2002]

The sunshine is rather 1000W / m², the panels a little more than 100W / m².
With 2 m² you could advance directly, to charge it depends on the charging time.
The battery has a capacity of 360Wh, with a panel of 100W it would take 3.6h (36V, 10Ah and not 10A!), Theoretically. In fact a little more because of several losses in yield, because the panel is never oriented at 90 °, and its power rarely exploited except with an mppt regulator.

[moinsdewatt]

.....
The yield of the photovoltaic cells used would be 20 times higher than traditional pv cells, ...

pipetting here too.

The well-made PV solar produces 20% efficiency.

it is therefore impossible to do better than 5 times better to reach 100%.

[Remundo]

Surunitary PV, mazette! Another cause of infarction for Lessdewatt ...

[Christophe]

You have roasted my friends ... a good PV makes 15% of return, the best 20% ... and 15 x 20 that 300% ... forget nothing to do!
Another blogger Hans Kremers (probably a pseudo *) who likes to spread the false truth on the net ... the worst is that we manage to find these kinds of intoxicants! (surely thanks to fuckbook!)

Thanks to Dirk Pitt, here present, for having commented on this deception on the blog in question ...

* Hans Kremer
Landscape architect, bicycle specialist, active mobility consultant.

No kidding!! If you graduated as an architect from a public school, well, I'm Max Born !!

[Grelinette]

Well ... this announcement, ultimately, is:
- either pure Hoax,
- is an uninformed writer in the technical subject of his article and who thought he had a scoop,
- either, like the front wheel of the bicycle, a lark mirror for naive investors, (possibly with an accomplice editor!)
- be a little of all that!

In short, let's drop the subject.

On the other hand, a technical point seems to me interesting to develop: the installation of solar panels on a mobile support :
Does the fact that PV panels move under the sun's rays affect their performance?

I am not talking about the change of angle PV / Rays-Sun which inevitably will be sometimes at best, sometimes at worst, but of the movement in itself. I see for example the fact that the movement will cool the PV, and from what I read, modify the efficiency (down).

This remark also concerns the various projects of vehicles with on-board PV, which are often placed on the roof of the vehicle therefore perpendicular to the sun's rays, but does it make sense, for example, to cover the blades of large wind turbines with PV?

Or more original, design translucent wind turbine blades that contain PV whose inclination is optimized with respect to the sun's rays? ... airplane wing ribs] ribs in aircraft wings, besides the big blades of wind turbine are surely made like that).

And even better PV (internal to the pale) on axes allowing them to be placed at best according to the solar radiation and the position of the pale? ....

(Hum ... my business truffle truffle which rises in the breeze of good deals, tells me that it still patent this case! )

[moinsdewatt]

I see for example the fact that the movement will cool the PV, and from what I read, modify the efficiency (down).

...

It is the opposite, the efficiency of Silicon Cells is better when they are cooled.