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Two Interview excerpts in Africa, from 2018, about Clean Coal

Professor Rosemary Falcon heads the Sustainable Coal Research Group at the University of the Witwatersrand (Wits) in Johannesburg, where the late Nelson Mandela studied law in the 1950s.

Falcon leads a team of nine academics along with 20 Mastersand doctoral students who, with their own laboratory at Wits, say they have proved conclusively that clean coal is not only possible, but among the cheapest ways to generate electricity on a continent where more than 600 million Africans live without power.

“It starts by understanding that coal varies enormously,” she said.

Each region has a different recipe of minerals and fossil matter, and if you give me a lump of coal out of Kenya, the US, Europe, India or Colombia, I can probably tell you where it’s from.”

In North America, she said, coal was formed in hot, steamy swamps, and it burns rapidly. Ours was formed at the end of an ice age and burns for longer and at a higher temperature

“An industrial boiler from Europe, fed with South African coal, will melt because our product burns so hot. But we also have more ash that actually absorbs heat, making the fire less efficient. So one of the first steps is to alter the coal before you light the fire. Or build a boiler designed for each coal type.”

Working with Falcon is Dr Nandi Malumbazo who took her PhD in chemical engineering at Wits. “In Africa, the use of coal is growing and that’s something we have to deal with,” she says.

“The challenge is to burn it more cleanly and this starts at the mine with techniques we’ve developed to separate poor quality coal from the better stuff that is already less toxic.

“You then crush it and remove elements that will not contribute to a good burn. Like unleaded petrol, you’re starting from a better place. Less ash, less fumes, more heat and a longer burn. From there we’ve done experiments and written up peer-reviewed research to show we can use it way cleaner than in most countries.”

The Wits research has drawn praise from across the continent. Dr Samson Bada of Nigeria has joined the team, along with Dr Jacob Masiala from the Democratic Republic of Congo. Both are working on ways to get the lights on in Africa and keep the air clean. There are also post-graduate staff and students from Zimbabwe, Botswana and Mozambique.

“If we mix pulverised coal with bamboo, something that grows well in Africa, we take emission levels down even further,” said Masiala.

“Of course, a bamboo plantation also gives you carbon credits, and we can grow it on old mine sites to rehabilitate the ground. It’s a winner on so many fronts.”

[https://www.dailymaverick.co.za/article/2018-03-15-op-ed-clean-coal-is-the-way-to-power- africa-and-sa-academics-know-how/]

Roger Crisp

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Peter Davies's avatar

Here are the facts on a couple of misunderstandings in the article. Firstly, it doesn't matter much whether UK solar panels are made with power from oil, gas, nuclear or wind. A solar farm lasts 30 years, with a 15 month energy payback in not so sunny Northern Europe. Elsewhere, the energy payback is less than a year.

A 104 MW UK solar farm generates 11.5 MW (11% capacity factor) x 8,760 hours/year, so 100 GWh/year. The output saves UK gas power and 50,000 tonnes of CO2 per year (at 500 gm/kWh). If the solar panels are made using 100% coal power (twice the emissions of gas), it takes 3 years of a 30 year life to break even, so the saving is 90%, 45,000 tonnes/year.

China was 62% thermal supply in 2024. So the saving per year is 47,000 tonnes of CO2 vs 50,000 if the panels were made using renewables. The use of coal in China hardly affects the CO2 savings.

Secondly, China is busting a gut to peak coal use and installed more solar and wind than the rest of the world put together in 2023 and 2024. Wind and solar power has a lot of curtailment recently, as the transmission grid hasn't caught up yet.

If you project the current trends, Michael Barnard reckons by 2035, China will have lower total CO2 emissions than the USA. See https://cleantechnica.com/2024/09/30/china-likely-to-have-lower-ghg-emissions-than-usa-by-2035/. China will expand renewables installed per year even further and will soon be dramatically cutting total generation from coal. Even while it keeps all its coal plants open to handle occasional peak times when the wind speed is low and it is cloudy - it will be using coal as the resource to balance its grid.

There is a huge difference in having huge coal capacity for backup, while reducing the TOTAL use of coal as a grid fuel. Only use counts for CO2 emissions, not capacity installed. China will get rid of most coal use by 2035, but the USA won't be able to reduce CO2 emissions (from coal, gas and oil) as fast, due to Trump's policies. China will catch the USA.

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