The most preposterous solution I have heard for our electricity problems is this: by installing 10,000 MW of renewable power and 5,000 MW of battery storage, we could, within two years, “stop load-shedding in its tracks”.

Let me tell you exactly what 10,000 MW of “renewables” and 5,000 MW of batteries would do. It would send electricity prices soaring; it would make load-shedding worse; it would put horrible strain on our electricity grid; it would further damage our economy; and it would cause horrible, long-lasting environmental harm, mainly in poor countries. (I assume here that by “renewables” they mean solar and wind rather than nuclear, which is in fact as renewable as they are.) Solar and wind for grid electricity have proved everywhere, without a single exception, an expensive disaster.

This profound nonsense scares me. It makes me fear that superstition has taken over from rational scientific thought. In 1959, in Cambridge, C P Snow delivered his famous talk, later turned into a book, on “The Two Cultures and the Scientific Revolution”. He said that most people in power in our governments and most people of influence in our media haven’t got the faintest clue about even the basics of science and engineering, while those who have are ignored or sidelined or mocked. 

The horrible mess of energy supply throughout the world right now is caused by exactly what Snow feared. People knowing nothing about the engineering of energy are behind the ruinous drive to “green energy” that has wrecked energy markets, sent energy prices soaring, ravaged the environment, further impoverished the poor and has caused riots around the world, and even the overthrow of government in Sri Lanka.

Let me explain why the suggestion is nonsense. I must give some boring arithmetic and energy essentials. Please skip them if you’re not interested and go to the arguments that follow it.

Power is energy divided by time; energy is power multiplied by time. Power is measured in Megawatts (MW) or kilowatts or other multiples. Energy is measured in Megawatt-hours (MWh) or kilowatt-hours (kWh). A power station has a rated capacity in MW. The longer it keeps generating electricity, the more MWh it will produce. A battery has a rated capacity for power MW (or kW) and for the energy it can store (MWh or kWh). The load factor of a generator gives the amount of power on average it actually produces compared with its rated capacity to produce. If a generator has a rated capacity of 100 MW, but over the year it only produces 60 MW on average, its load factor is 0.6 or 60%. For nuclear, the load factor of modern stations is about 90%; for coal about 70%. In South Africa for wind, it is about 32% and for solar photovoltaic, about 25%.

The South African grid now has a maximum demand of about 32,000 MW (at evening peak) and a minimum demand of about 20,000 MW (in the small hours). The ratio of maximum to minimum is only about 1.6. Furthermore, demand is very predictable. If you have sufficient electricity, it makes perfect sense to store electricity in off-peak times by pumped storage to deliver it in peak times.

Load shedding in South Africa comes in various stages. In Stage One, 1,000 MW must be shed. In Stage Two, 2,000 MW, and so on. If you want to prevent Stage Four, you must be able to ensure an extra 4,000 MW of electricity. Let’s see what 10,000 MW of renewables would do.

Assume a load factor for solar and wind combined of 29%. This means, on average, 10,000 MW of solar and wind would generate 2,900 MW, enough to avoid Stage Two but no higher stages. However, this is on average. In practice wind and solar output vary violently and unpredictably, as can be seen by looking at the production graphs of our disastrous Renewable Energy Independent Power Producers Procurement Program (REIPPPP). 

At one time on 8 October 2019, solar and wind, with a capacity of 3,954 MW, were producing only 45 MW. That is 1.1% of the installed capacity. If the 10,000 MW of renewables were producing 1.1% of its capacity, they would produce 110 MW. (On other occasions they have produced 99% of their rated power. So while grid demand only varies by 1.6 to 1, renewable production can vary by 100 to 1.) Planners must allow for the worst reasonably likely outcome. Energy planners would have to say, “If we have another 10,000 MW of renewables on the grid, in the worst likely outcome, they will only produce 110 MW on some occasions.”

What about 5,000 MW of batteries? I assume that the people who make this ludicrous proposal mean that the 10,000 MW of renewables should charge the 5,000 MW of batteries. (It would be absurd for the batteries to be charged by Eskom in non-load-shedding moments. If so, they would be taking 5,000 MW to put 5,000 MW back, with losses.) Looking around the world, at small and big batteries, it seems roughly true that a 1 MW battery can store about 1 MWh of energy and be charged with 1 MW in about one hour (these assumptions are somewhat generous). If the total average power of the 10,000 MW of renewables is 2,900 MW, it would mean that if their total input went into charging batteries, it would take 1 hour 40 minutes to do so. In the meantime, not one kW would go into the grid, so doing absolutely nothing to stop load shedding. Then when the batteries were fully charged, they would be fully discharged in less than one hour of Stage Six load-shedding. Then recharging would have to begin again.

It’s absurd. It’s a fantasy. It’s even worse than the make-believe models of the CSIR or our ridiculous IRP2019 (Integrated Resources Plan).

What about the environment? Solar and wind use massively more natural resources than nuclear. Wind turbines use over ten times more steel and concrete than nuclear per kWh. Solar and wind both use toxic materials that remain dangerous for thousands of millions of years, and no one has any plan for disposing of them safely – unlike nuclear, which can dispose of its wastes safety and easily. 

In Baotou, in northern China, the filthy mines producing the rare earths used in the wind generators in Germany’s energiewende are causing death, disease and infant deformity in the poor Chinese communities near them. Batteries, required by the rich elite in the West, need minerals such as cobalt and lithium, which the elitist greens will not allow to be mined in their rich countries; so they have to be mined in poor African countries, often by little children in dreadful conditions.

What about costs? The costs of 10,000 MW of renewables would probably bankrupt our economy. All around the world, you can see the full cost of electricity (FCOE) from solar and wind going up, up, up as more is added to the grid. The greens don’t want to tell you the FCOE; they only want to tell you the cost of the rubbish leaving the wind turbine or solar array when it happens to be generating.

Costs of batteries? Suppose you went in for small-scale household batteries, which are freely available. On the web I see that a “Freedom Won Lite Home” battery, which can produce 10 kW for five minutes, costs R66,400. To provide 5,000 MW of these would cost R33 billion, but they could only produce 5,000 MW for five minutes. If you wanted big batteries instead, the biggest until recently was Elon Musk’s battery installed in South Australia after wind power had caused two total state blackouts in 2016. It had a capacity of 100 MW and can produce that power for just over an hour; it was said to have cost $90m Australian (R990m). (It was a total failure for storing grid electricity.) To provide 5,000 MW battery storage, we should need 50 of these, costing R49 billion.

C P Snow’s fear that the scientifically ignorant, who hold the power and the influence, might doom us, while the scientifically knowledgeable, who are often timid, inarticulate and subdued, surrender is proving all too true. We have all the resources and skills needed to provide clean, affordable, plentiful, sustainable energy for everybody on this planet but we are not allowed to employ them. Are the people evil who are denying us a happy, healthy world? Not at all. They are often – not always – thoroughly decent folk, completely misled by the fashion of the hour. Let me give two examples.

On 8 July 2022, Business Day carried an article entitled “Easy solutions to power crisis but dimwits are in the way”. It was by Peter Bruce, who proposed again that 10,000 MW of renewables and 5,000 MW of batteries would end all loadshedding. He is the former editor of Business Day and the Financial Mail. I have never met him but have conversed with him. He is affable, liberal, cheerful and intelligent. He writes well and easily, so that his articles are a pleasure to read. He is prepared to be original. At Business Day he published articles and letters of mine with which he disagreed. He now has a column in the Sunday Times, where he wrote about this magic solution to the energy crisis. I criticised it in a letter to the Sunday Times, which to my surprise was published. The inspiration for his silliness is Professor Mark Swilling of the University of Stellenbosch. Professor Swilling has a PhD in Sociology. Think of C P Snow’s two cultures.

In my letter to the Sunday Times, I challenged Bruce and Swilling to put their money where their mouths are, and do it at home. To run a national grid on solar, wind and batteries is not only catastrophic for the environment and the economy but impossible. However, it is possible, although at a huge cost, to run a household on them. I challenge Bruce and Swilling: cut off your electricity connection to Eskom or your municipality; forsake gas, coal, diesel and other CO2 emitting fuels; and run all the heating and cooking for your house throughout winter with just solar, wind and batteries.

Go on! Do it! And report back to us with all the expenses and energy usage.



Andrew Kenny is a writer, an engineer and a classical liberal.