All you really need is a Solar panel, charge controller and a battery. A Panel that outputs 1 amp for instance will fully charge say a 7Ah battery in 7 hours of sun. The charge controller maintains the battery, keeping it from overcharging and if the controler has low voltage detection it'll keep the battery from discharging TOO far. The Trace C-12 controller for instance does this. I use a Unisolar US-5 panel (5 watts, .300 amps), a Morningstar Sunsaver 6 controller and a 4 Ah battery. It runs my MFJ 9040 on recieve for quite a while, transmit is a different story. I'll get a large capacity battery and larger output panel soon though. There are LOTS of web sites about solar power, just do a search. Hope this helps. 73 de Tom