Solar FUN

Here at Alterra our focus is usually on scoring a nice residential or commercial PV job. However, I recently realized there are those who would love to get their feet wet with some small solar application that would be both fun and inexpensive. Something that costs hundreds, not thousands. So, myself and friends
have been brainstorming fun projects one could do with solar energy. It could be practical or some visual spectacle.
Projects usually fit into three levels of system sophistication. (expense)
1) Direct drive: a properly sized array connected directly to a motor or pump. Just a switch and a fuse for safety. No sun, no run.
2) PV array, charge controller and batteries: This could run a low voltage appliance or lights with the reserve power for night use.
3) PV array, charge controller, batteries, and inverter: This system can provide auxiliary AC power for computers, TV, audio, small tools, and lights. Perhaps even a circuit in your house if you put in a transfer switch on that circuit.
I have two direct drive pieces on the property. One is a pond aerator using just panels, two submersible pumps (12vdc), some tubing and spray heads. The system should pump 1500 gallons per hour from the pond bottom (12 feet) and spray the water into the air at the surface. This will help oxygenate and turn over the bottom anaerobic water. Nutrient load and rotting vegetation causes this dead zone. (eutrophication) The other device is a simple solar whirlygig to attract passerby attention on US 219. Its a 180 watt panel with a 24vdc gearmotor spinning crabpot bouys. Most people think its wind driven.
Another application is as an electric cart charger. The blue cart has a single 60 watt panel on the roof. It acts like a range extender giving you more time between grid charges.
My brother, Jeff Hoffa, has a 60 watter on the cart and an aditional 120 watts on the roof. He made a charging station so he can plug in the cart for a total of 180 watts. He has no charge controller but he does have a volt meter mounted in the cart so he can manually control the maximum charge voltage. Since he does not use his cart as much as we do, he'll have a surplus. Since the battery pack in a cart is 48vdc and about 8 kWh of storage. Thats enough reserve to justify purchasing an inverter to use as emergency house power or use as a small single circuit supply.
Just think of the many uses and the fun it would be to construct a solar power kinetic sculpture or water fountain. We have several 12 volt and 48 volt panels available for $1.49/watt ( $80 something each panel) We will be developing small installations and contraptions as time goes on and posting some simple plans on our website. 'Til then dream something up and get a taste of solar.