Non renewable energy from our dwindling fossil fuel reserves are cheap because although they were collected over thousands of years, we are allowing them to run out without consideration of the consequences. Solar energy can be considered as infinite in terms of replacement. But the cost of collecting it is currently higher than electricity from fossil fuels. This situation will reverse itself at some time in the not too distant future.
On the left is a picture of a typical set up. You can get them here. This one is shown wired up and ready to go. It has a 30W panel but you can get kits with smaller panels.
This system has been proven to work satisfactorily.
If you want the system to last there are a few things you should try to avoid.
Never short out the wires from the battery or the solar panel. If you do you may damage the solar panel or melt the wires from the battery. Even thought the voltage is only 12 volts and can’t give you an electric shock, the hot wires could get hot enough to burn you.
Don’t leave the pump running for longer than its recommended duty cycle. Low cost 12volt pumps are not designed for continuous use.
Use a good switch to turn on and off the pump.
Keep the water being pumped clear of material that could block the pump. Don’t run the pump dry. ie Don’t plug in the pump until the pump is in the water.
Solar panel alignment is not critical. For optimum results in the UK it should be approximately 70 degrees from the vertical and facing south. The battery should be a 12Volt lead acid (leisure type if possible). The pump also needs to be a 12 volt, preferably a submersible.
Possible component sources: Pump International.com or Online pumpshop.com
These sources have been chosen because they are direct sources and direct importers rather than distributers or retailers. Their costs generally reflect this. They often have large stocks, lower overheads and hence charge a lot less. Due to the Internet it is now quite possible for purchases to be made direct from these wholesalers rather than from a retailer.
See links below
You can make up your own kit if you understand what you are doing. It’s not a good idea to leave out the controller unless the panel is very small and the battery is very big ie panel about 5W and battery a larger leisure battery. This is because it is quite easy to damage the battery by over charging it.