Confused by numbers

James Green, SESSA Solar Water Heating Chair

The confirmation last week by South Africa’s super telescope, of the distance of the latest supernova found by Chile last year at 3.8 billion light years away is confusing. As the speed of light travels a little over 1 billion kilometers an hour, it is just a very long way away.

More down to earth figures of Citibank withdrawing SAA’s line of credit of R250m, I can get my head around. Even the universities needing an extra R3billion at a minimum is understandable, and probably R30 billion. The cost of the drought at untold billions, and then what about South Africa’s nuclear plans? Estimates were a trillion Rand, but since the Rand has crashed that has probably increased in cost by a couple of hundred billion or more. A billion here, a billion there, the numbers just don’t seem to be really understood by anybody. Even a Presidential jet at R4billion is a sort of understandable figure.

And so to Eskom wanting to claw back some R22,8 billion of which R8 billion is for the overspend on diesel to keep the open cycle gas turbines (OCGTs) running in order to keep the lights on. Not surprisingly the Nersa public hearings are charged with emotion, with farmers and others spouting valid statistics as to what a potential increase in the cost of electricity over 8% per annum will cost them. But the reality is that load shedding causes industry, including farming, far more than the cost of the diesel in lost revenues, let alone the staggering inconvenience of being denied an essential resource, and the government told Eskom to keep the lights on whatever the cost. 

In contrast to these hugely misunderstood numbers there are approximately 7m electric geysers in South Africa, and they each consume 10 or more kWh per day, and much of it is during Eskom morning and evening peak periods, when Eskom has to turn on the OCGTs. Eskom calculated a couple of years back that the cost of these kWhs during peak was running at over R4 each, falling back to R3,25 as the price of diesel fell.

Solar power of course is free, other than the cost of the equipment and installation, and South Africa has a lot of it. R8billion of diesel could have funded, or heavily subsidized nearly 1m solar water heaters saving kWh’s every day for up to 25 years or more. 

For comparison purposes R8 billion at R4 per kWh is about 2billion kWhs. 1m SWH at the same cost of R8 billion would save 73 billion kWhs over 25 years. Value for money is obvious and solar reduces carbon emissions as well.

Of course the numbers are illustrative, comparing fruits is never quite the same, but the value of consumers saving electricity at home and in business is undeniable. Add in the carbon savings and climate change mitigation, and solar becomes a progressive no brainer. 

While the government pursues energy policies, based on rather out of date assumptions IRP 2010 and 2013, and plays spreadsheets with billions, which almost certainly can never be afforded for nuclear, the consumer can get on with it, saving kWhs and making the need for nuclear redundant.   

As we go into 2016 and following COP21, South Africa needs to really start embracing energy saving. Solar Water Heaters are the place to start, as they are energy intensive and consume 40-60% of the average domestic electricity bill, followed by energy efficient lighting, and then solar photovoltaic for home and business electricity generation.  

Small numbers (kWhs) which everyone can understand, will if a lot of people embrace renewables, cumulatively add up to huge numbers of kWhs (billions over time), and those consumers that are energy efficient will be better off financially than those that don’t. Simple really, and it is for free.