Reality check to the claims of increasing the range of an electric cart by 50% with the addition of a solar panel:
Since the owner of the cart that hasn’t been connected to shore power for years and puts out many more “amps per day” than 1-2 amps will not reveal the specs for his cart, I will offer a reasonable estimate.
A typical high efficiency solar panel that is 3’x5’ (reasonable size to put on the top of a cart) puts out 275 watts at standard test conditions (1000 watts/M^2 of sunshine). The typical real world energy density you can expect for a full sunny day is 800 watts/M^2. At this density that panel puts out 205 Watts.
This energy is delivered at approximately 31 to 35 volts depending on load. Since the golf carts run on 36 or 48 volt nominal voltage, a DC to DC converter is required to convert the solar panel output to a voltage that would be able to charge the batteries. This converter even if 85% efficient would reduce the usable output of the panel to 175 watts. At a 48 volt nominal battery voltage that would be 3.6 amps.
The typical cart riding around the Villages draws 25-150 amps depending on whether they are coasting, climbing an incline, extra weight in the cart, etc. Additionally, the weight of the panel, mounting hardware, wiring and converter would be equivalent to an extra battery in the cart (approx. 65 lbs), further reducing the usable energy from the solar panel.
So as a previous poster alluded to, if you travel slow then park in the sun for a reasonable period of time, rinse wash, and repeat, you will get a minimal increase in range, over batteries only.
As to not having to ever connect the cart to shore power, you will either need a big hole in your garage roof to let in the sun or park the cart outside, neither option is very desirable.
Just my opinion, I may be wrong.
|