nick2earth said:
I have no problem moving the post if necessary!I dont know how though
Any moderator/admin can move the post if you need to.
The details are the usual calculations and parts available on the market that are discussed all over the forum,nothing strange or new i just figured that it is possible at the moment to make a light ev-bug and every 8 hours of sun have enough battery to move it around town for 40-50km.
At what speed, and what acceleration rate do you expect?
Both of those will decide a lot of how much power you'll eat up, and thus how much it'll take to recharge it.
Car-sized vehicles for the most part take quite a lot of power, much more the faster you go, and much more the faster you intend to accelerate. Accelerating fast enough to not be run over by cars behind you at a stop will usually take up to several times more power than if you just gently get started over a long distance, and the heavier it is the worse the problem, especially on any upward slope/hill.
I personally doubt you can put enough panels directly on a vehicle to get enough capacity back into the batteries in 8 hours to go that far at typical car speeds. At slower 20-25mph speeds, maybe, but probably not even that.
Remember that
-- panels that are not perpendicular to the sun are not going to get nearly the amount of power output that they could, and
-- most panels are not even 30% efficient to start with before they get hot, and that
-- most places even under perfect conditions you won't get more than 500w/square meter worth of sunlight anyway, probably less than that on average given angles of sun to panel change thru the day, and
-- anything fixed to the vehicle surface won't be able to stay pointed at the sun, and will get less and less power as the angles change away from perpendicular.
Using maxeon cells and a light bldc motor with sine wave controller are my thoughts.
I have a sepex motor/controller set from my g-wiz but the motor itself is around 35kg and 4.8kw continuous.
6-7 sq meters of cells covering the body panels of the bug is the key idea.
Let's be optimistic, and say you get 7. Then say there's 50% of the possible power of 1kW always falling on them, for a total of 3500W input to the panels.
So let's say the panels are superefficient and, so you get 50% of the input power out of them...that's 1750W.
Let's say your converters are 80% efficient at the output point of the panels, so you get 1400W out, constantly.
That, over 8 hours, would net you 11.2Kwh of energy into the battery.
Let's say it only takes 300wh/mile for your vehicle including all it's controller/motor conversion efficiencies, then you could actually get up to 37miles / 60km or so, whcih would more than meet your goal.
But I suspect all those numbers are much more optimistic than you'd actually get--you'd have to do the experiments, math and calculations first to see what you'd actually get out of the panels thru a whole day, what the efficiency is of your conversion processes, what the vehicle would take for power consumption, etc.
I'd be interested to know what all those numbers really are for your project.