Solar Water Pumping
Water pumping is a wonderful use for alternative power technology. Even if your ranch house is powered by conventional power from the grid, what about getting water to your cattle on the back 40? Windmills have been used for over 100 years for this purpose, but other alternative power methods are effective too. Really, ANYTHING is better than pumping water by hand, but gas powered generators are the worst of the bunch
Power for Water Pumping
Solar- Solar technology is very well suited to pumping water, even more so than the traditional windmill. A typical system includes one or more solar panels, an efficient 12 volt DC pump, a controller (with float switches), and a "linear current booster" (more about this later). As long as it's daytime and the float switches show that the water source is not empty and the cistern in the house is not overflowing, the pump will run. The linear current booster allows the pump to run even if it's cloudy out.
Wind- The traditional windmill is still useful technology. The pump is directly coupled to the wind generator. The only problem comes if there is no wind for a few days at a time, and with maintenance. The leather seals on this sort of pump wear out and require replacement. The Bowjon windmill system uses pressurized air to pump water, and requires very little maintenance. It can also be used to generate power. Other systems have been built using an electric wind generator, linear current booster, and pump, as described in the Solar section above.
Water- Yes, water can be used to pump water. The device involved is called a "water ram." It uses your local stream's water pressure to move a fraction of the total stream flow uphill--as much as 30 times the total fall. Water rams can be purchased, or built at home with PVC pipe and valves. Look for more information on this here in the future.
Gasoline- A waste of resources. Avoid it if possible.
Hand Pumps- Better than not having water, if you have no resources available.
Solar-Powered Water Pumping System Configurations
There are two basic types of solar-powered water pumping systems, battery-coupled and direct-coupled. A variety of factors must be considered in determining the optimum system for a particular application.
Battery-Coupled Solar Pumping Systems
Battery-coupled water pumping systems consist of photovoltaic (PV) panels, charge control regulator, batteries, pump controller, pressure switch and tank and DC water pump. The electric current produced by PV panels during daylight hours charges the batteries, and the batteries in turn supply power to the pump anytime water is needed. The use of batteries spreads the pumping over a longer period of time by providing a steady operating voltage to the DC motor of the pump. Thus, during the night and low light periods, the system can still deliver a constant source of water for livestock
[LEFT]Battery-coupled solar water pumping system
[B]Direct-Coupled Solar Pumping System
[/B]In direct-coupled pumping systems, electricity from the PV modules is sent directly to the pump, which in turn pumps water through a pipe to where it is needed. This system is designed to pump water only during the day. The amount of water pumped is totally dependent on the amount of sunlight hitting the PV panels and the type of pump. Because the intensity of the sun and the angle at which it strikes the PV panel changes throughout the day, the amount of water pumped by this system also changes throughout the day. To compensate for these variable flow rates, a good match between the pump and PV module(s) is necessary to achieve efficient operation of the system. Direct-coupled pumping systems are sized to store extra water on sunny days so it is available on cloudy days and at night.
Direct-coupled solar pumping system.