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How we can keep burning (clean) coal for 100 years

The American engineer helping Australian coal miners prepare for a low carbon future has good news for his donors Down Under. “It will work for coal,” says Jeremy Fetvedt, during a conversation with the Tech Zero podcast about his work on a low carbon, coal-fired power station that bears his name.

Mr Fetvedt was a key player in the NetPower joint venture which last year delivered electricity into the Texas power grid from a pioneering gas fired power station that is said to capture more than 97 per cent of the carbon dioxide emitted during combustion. He is now working to adapt the power station to run on coal – a project partly funded by Australian coal miners – in the belief that even the most unfashionable fossil fuel can be made clean.

Dubbed the Allam-Fetvedt cycle after its two main founders – Rodney Allam and Mr Fetvedt – the project spent last year burning methane gas in pure oxygen and ultimately produced a highly concentrated stream of carbon dioxide within a closed loop that would be suitable for permanent storage or industrial use. By contrast, the carbon dioxide emitted by traditional gas power stations is often mixed with nitrous oxide, sulfur dioxide and other particulates, meaning further time, money and energy is required to separate carbon dioxide from those flue gases before it can be permanently stored.

Australian coal miners were so impressed by the gas trial, they pledged $US5 million to Mr Fetvedt’s team in 2020 to fund an adaption of the Texas gas power station to run on coal. The money was invested via the Australian coal industry’s research and development organisation Low Emissions Technology Australia (LETA), which was previously called Coal21.

Mr Fetvedt told the Tech Zero podcast that adapting the Allam-Fetvedt cycle to run on coal was relatively simple, requiring the mere addition of a device that first heats the coal and produces a synthesis gas (syngas) which can be fed into the existing power station. While the coal trial is only half complete, Mr Fetvedt said he was confident there were no major technical barriers.

“It’s a very well known, understood process, to gasify coal and just take the syngas into the second process,” he said. “Some of the lead times for the equipment involved do border on years, so it’s another year or so on project.”

A solution for ‘hundreds of years’
Asked whether the Allam-Fetvedt cycle was a “transition technology” that would only be viable for a short time before renewables and storage took over, Mr Fetvedt said he believed the technology would pass the test of time. “I personally think it’ll be a solution that’ll be running for hundreds of years,” he said.

The Allam-Fetvedt cycle does not provide a carbon storage solution; Mr Fetvedt says that is up to the customer to solve and different locations will suit different storage solutions or uses. “It depends upon where you are and where the local industry is, what the local geology is, what the local experience is,” he said.

LETA has called for an Allam-Fetvedt cycle power station to be built above geological storage locations in Queensland and believes the technology could also be used to make hydrogen from coal without emissions. LETA also joined Santos last month in lamenting the Albanese government’s decision to cut $250 million worth of funding for carbon capture and storage projects in last month’s federal budget.

Netpower is a joint venture of Fetvedt’s employer 8 Rivers Capital, oil giant Occidental, transmission company Exelon and several other energy services companies.

While the Texas power station housing the coal studies is a trial facility, Fetvedt’s employer 8 Rivers Capital has proposed the construction of permanent Allam-Fetvedt cycle power stations in the US states of Colorado and Illinois. Investment decisions on those two projects could be taken before the end of this year. The coal trial is actually a return to the original ambitions for the Allam-Fetvedt cycle power station; it began as an attempt to produce clean coal-fired power but was refocused onto gas-fired power in a bid to find a simpler, faster path to market.

https://www.afr.com/companies/energy/how-we-can-keep-burning-clean-coal-for-100-years-20221104-p5bvpj