Water Pumping and Irrigation

Water pumping is one the better applications of solar energy.  It can be used to serve small cabin sites to small village sites.  The total well delivery is the major factor in determining the type of system that is needed.  The most efficient system is a cistern (or holding tank) system because it can accommodate various well delivery rates. 

In the case of smaller water systems, the water is delivered at low pressure to a cistern, which when full, shuts the power off to the pump via a float switch.  At this point, the water can be used at its static low pressure.  Once this condition is served, the photovoltaic electrical d.c. power can be diverted to charging storage batteries, which then can be used to deliver low voltage d.c. power, or it can feed an inverter to provide higher voltage a.c  power.

In the case of an enclave of homes, i.e. small village, the water can be shared, but often there will be water hogs which can cause strife.  To remedy this problem there can be a pre-arranged water amount per home per day.  This can be accomplished by starting with fixed starting water storage per home, with identical high pressure pumps at a known delivery rate.

These pumps are controlled by secured seven day timers at a set run time per day. If there are water hogs, they will have to live within their pre agreed allotment.  This system will have to be designed with in the delivery limits of the well.