It's summer in America and I've heard its pretty hot this year; if you have a swamp cooler otherwise known as an evaporative cooler then you can try this handy guide to convert your swamp cooler to run on solar power.
This would be awesome if you loose power during the day; you will still be able to cool your house down.
This guide was found on eHow; its one of my favorite sites.
Instructions to convert your swamp cooler to solar power.
Disconnect the swamp cooler from the main electric supply. Check the outside of the cooler for a label that tells the measurement of electrical current in amps that the unit uses. Calculate how much power the solar panels will need to provide to the cooler. Power in watts is given by multiplying the current in amps by the voltage in volts. For instance, if on the outside of the cooler the current is given as 1.4 amps, then multiply this number by the mains voltage of 115 volts. This gives the electrical power as 1.4 amps times 115 volts which is equal to 161 watts.
Decide how you want to do the conversion. You have two choices. The first option is to replace the electrical motor that runs the fan or blower in the swamp cooler, together with the small water pump, with new units that run on direct current, or DC, electricity. This type of DC equipment is available for either 12-volt or 24-volt DC power. You will need to replace the motor and the water pump with a DC motor and pump, and connect the swamp cooler directly to a solar panel that generates enough power for the cooler. The second option is to convert the DC electricity from the solar panel to 115-volt AC by using an inverter. This way you don't have to replace anything inside the swamp cooler. You just plug the cooler straight into the the inverter. Each option has advantages and disadvantages. In the first option, you essentially have to rebuild the cooler. In the second option, you have to buy and install additional equipment: a battery, a charge controller, and an inverter. This may work out to be more expensive, but technically it is the more efficient option. It also allows your cooler to work at night, which is not possible with a direct solar system............ please read the rest at eHow.