Eskom and the media's scientific illiteracy

Summer reduction in capacity!

South Africa’s minister of electricity makes a factual statement based on basic thermodynamics and the media doesn't understand it!

https://twitter.com/eNCA/status/1703365442406895959

The efficiency of a Carnot Heat Engine is a well known problem in thermodynamics. It can be used to demonstrate his argument that powerplants are less efficient during the summer!

• Ambient Temperature at Elisras during Winter is approx. 26°C i.e. 299Kelvin

• Ambient Temperature at Elisras during Summer is approx. 34°C i.e. 307Kelvin

Coal Power Stations under ambient conditions run at around 33% efficiency.

If you do the above exercise it turns out that the change in temperature should theoretically result in a a 2% decrease in efficiency for Elisras.

Matimba Power Station has 4000MW of Power, i.e. a theoretical 80MW of loss during summer.

Multiply that with Eskom’s 30GW of available capacity then it’s about 600MW loss.

Just over half a stage of load shedding.

The sad state of South African Science and Mathematical Illiteracy is going to be our undoing.

Disclaimer: coal station’s aren’t perfect Carnot Systems, the above calculation only shows the principle.