Solar Systems Applications in Cape Town

• Background:– DmE projected impact of RE in 10 years is dismal (10 000 GWh/pa)– Because it is judged against poor electric conversion efficiencies– Solar water heating has been suggested to by-pass this shortcoming– Highest impact however would be on peak demand losses on

ESKOM grid– Cape Town have ambitious target of 10 000 solar heaters (by 2010)

• Objectives:– Impact of solar heaters on grid peak demand– Projections of energy and line loss savings on a nationwide

application

Solar Systems

Case Study: Blombos Pilot Solar Water Pumping

• Background:– Blombos lies about 300 km on Cape Town’s west coast

– Farm needs: water pumping

– Commercial system cost: R33k

• Approach:– Used latest state of the art equipment - not archaic solar maps!

– Used wind to advantage: raised the panel up

Solar Systems

• Outputs:– Solar panel driven pump system

– Farmer had more water than needed!

– Cost of R13k (40 % of original spec!)

• Comments:– Over-design ignorance increases costs

– Need to move away from obsolete methods

– Additional White LED installation for ultra-low power lighting

Optimization of Solar Water Pumping System using

Genetic AlgorithmsScope:

• Development of algorithms

• Collection experimental results

• Simulation

• Modifications

Solar Systems

• Pump type: SOLASTAR positive displacement pump for low head applications (< 100 m)

• Maximum Power Point Tracking is provided by an algorithm that monitors potential and current from the pv array.

• System simulations for:• Motor• Pv array

• Optimisation:• Analysis of conduction losses• Power dissipations• Other circuitry losses

Solar Systems