Page 157 - Alternative Energy Systems in Building Design

SOLAR POWER SYSTEM DEPLOYMENT 133

■ AC power production
■ Accumulated daily, monthly, and yearly power production

SOLAR POWER IN SMALL-SCALE WATER-PUMPING
APPLICATIONS
The solar submersible pump is probably the most efficient, economical, and trouble-free
water pump in existence. Figure 3.69 presents a diagram of a small submersed solar
pumping system. In some installations, the procedure for installing a solar power pump
simply involves fastening a pipe to a pump and placing the unit in a water pond, lake,
well, or river. The output of the solar panel is connected to the pump, and the panel then
is pointed toward the sun, and up comes the water. The pumps are generally lightweight
and easily moved and are capable of yielding hundreds of gallons per day at distances of
over 200 ft above the source. The pumps are of a rugged design and are capable of with-
standing significant abuse without damage, even if they are run in dry conditions for a
short time.
Pumping water with solar power is reliable and inexpensive and is accomplished
with a combination of a submersible pump and a solar cell panel that can be procured
inexpensively. Engineers have spent years developing a water-pumping system to
meet the needs of ranchers, farmers, and homesteaders. These systems are reliable and
affordable and can be set up by a person with no experience or very little mechanical
or electrical know-how.
In some instances, the pumping system can be equipped with a battery bank to store
energy, in which case water can be pumped at any time, morning, noon, or night, and
on cloudy days. The system also can be equipped with a simple float-switch circuitry
that will allow the pumps to operate on a demand basis. This type of solar pumping
system requires very little maintenance.

SOLAR PV ARRAY

WATER
RESERVOIR

BATTERY &
CHARGE CONTROL WELL SHAFT

WATER
TABLE
PIPE
FLOAT PUMP
Figure 3.69 Diagram of a water well solar-powered
pump.