The main objective of the work is to develop pilot systems of PhotoVoltaic driven displacement pumps for rural applications. The results will be useful in the development of future PV pumping systems and assist in the introduction of such high-efficiency pumping systems in remote areas of Europe and in developing countries.
The rotary displacement pump developed by WIP in Germany was tested at the French partner's laboratories. The pump prototype achieved a maximum efficiency of more than 53%. This is the highest efficiency of a motor pump unit ever measured at the French testing facilities. The hydraulic efficiency of the pump showed that it is ideally suited to high heads and low flow rates, which are the main requirements for water needs and borehole characteristics in developing countries.
For the piston pump, the ECN and Eindhoven University partners incorporated a special piston valve that had previously been developed for use with wind pumps to improve pumping efficiency. This piston pump was tested under laboratory and field conditions to investigate the influence of different pump parameters on the characteristics of the pumping system. Subsystem efficiencies above 40% were achieved for insolation values above 400 W/m2, and subsystem efficiencies of about 55% are expected in future if further optimisation work is performed.
In this project two innovative system designs are subject to further investigation
1) the rotary displacement pump and
2) the piston pump with matching valve.
For the rotary displacement pump driven by an ac motor most technical problems are solved. But small-size to medium-size PV water pumping systems do not necessarily require sophisticated inverters to drive the motor of a rotary displacement pump. Thus, in order to reduce cost and maintenance needs a dc motor driven rotary displacement pump with a specially developed power conditioning unit will be investigated.
The piston pump is a further promising alternative for water pumping. By modifying the piston pump torque characteristic with the implementation of an adjustable valve in the piston reducing starting torque, an optimum matching of PV generator characteristics and pump can be achieved. In the frame of the present project a pump with a valve optimally matched to PV generator characteristics will be developed, constructed and tested.
The expected results from this project are as follows :
1) An operational system of a dc submersible motor and a rotary displacement pump with a specially developed power conditioning unit.
2) An operational PV pumping system equipped with a piston pump with matching valve.
Funding SchemeCSC - Cost-sharing contracts
13108 St.paul Les Durance
1755 Petten Zg