At home, I use solar water heating as the first resort. If the water is hot enough, no further action is needed.
If not, I use a kettle to heat the water to the desired level. In this way, I save both water and electricity to complete my daily ablutions.
That got me thinking. Why is Eskom not using both solar thermal and solar PV to the extent that nature makes available each day?
We have abundant solar radiation year-round, that could be used to heat feed-water and generate electricity for internal use at the power station.
According to (researcher and author) C Gellings, “electricity from the PV system (can be) used to supplement the energy (required) to drive the plant.
A CFPS (coal-fired power station) can use up to 15% of its generation to drive the various items of machinery necessary to keep the plant running”. A 15% saving is nothing to be sneezed at.
Mike Rycroft, the feature editor at EE Publishers, explains that solar heat, at around 300°C, could be “used to replace the steam extracted from the high-pressure turbine” or “to pre-heat the feed-water before the economiser stage of the boiler”.
The article notes that this is being done in India, for example.
If Eskom could increase its efficiency in the same manner, it could get by with less coal and generate electricity more cheaply. Better still, it will reduce carbon emission through such hybridisation. Cherry on the top: no load shedding.
Cope Western Cape spokesperson