Nice summary.

The item "receiving 100 watts per square meter" is tricky. On a clear day
with the sun over head you may see 1300W/m^2.  But more usual is 1100 or
1000. Could be 200W/m^2 with clouds or heavy weather. And the sun,
unfortunately does not stay directly in front of a mobile array no matter
what you do.  Then you apply the 80% or probably more efficiency
reduction.  (I have heard that CA is more forgiving than most places when
the smoke dies down. And then then there is SF in the AM ...)

Calling it 100 W/m^2 is a swag, but not a bad one. It is just that it
washes out all sorts of sub-optimal situations that will inevitably occur.

Personally, I think a mobile array for a vehicle is a fools errand, or
maybe a pass-time for the independently wealthy.

On Thu, Dec 28, 2017 at 11:39 PM, Marc de Piolenc via EV <>

> You're getting power and energy mixed up.
> Your Leaf has a POWER rating of 30 kW, which means that (at full power) it
> consumes 30 kW-hours of energy per hour.
> It does not get 4.5 miles per kW because a kilowatt is a unit of power,
> not energy - maybe 4.5 miles per kWh which is roughly consonant with its
> power rating and speed.
> To support that speed without dipping into batteries, you need a solar
> array that constantly produces 30 kW, which at 20% efficiency, receiving
> 100 watts per square meter, will require 300/.20 square meters of solar
> photovoltaic panels, or 1500 square meters. Not easy to tote around.
> It is safe to say that you cannot generate enough juice to recharge while
> driving.
> On the other hand, having a much smaller array can still allow your car to
> recharge while it is parked in the open, and that might be worthwhile,
> depending on your application. This would work if you have a short commute,
> followed by the car being idle for nine hours or so in broad daylight in a
> sunny climate.
> Marc de Piolenc

Michael E. Ross
(919) 585-6737 Land
(19) 901-2805 Cell and Text
(919) 576-0824 <> Tablet,
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