I did some contract work a few years back for a friend of mine that had connections to the solar car race. After I was done doing the work, he asked how I wanted to be paid. Off the cuff, I said "how about in solar panels" ... So I ended up with ten 240Watt 24V solar panels. I mention this because I have similar motors that I use with the solar panels to drive a few fans in my barn. For what the OP is wanting to do, he will want at least two panels. (Sorry mine are not for sale) ... As mentioned 500 Watts is about right.... You want to figure immediate power requirements, and charging power requirements .... so if the motor is rated so that it matches one of the solar panels, then the additional solar should be the rate at which you can charge the batteries. 5 to 10 Amps is probably a good charging rate, and at 24V that's 120Watts to 240Watts of overhead that you will need to charge and ride at the same time.