The Commonwealth Scientific and Industrial Research Organisation (CSIRO) has partnered with US-based GTI in a Joint Industry Program to develop a supercritical CO2 (sCO2) power plant that could assist mining companies to reach large renewable energy targets.
When used with low-emission energy inputs, advanced sCO2 power plants have the potential to be a transformational technology that can accelerate the world’s transition to a low-carbon future.
“While most power plants use steam to produce electricity, sCO2 power plants use recirculating high-temperature CO2 instead,” CSIRO Research Director Energy Technologies, Dr David Harris, detailed.
“The advantage is that sCO2 is a higher density working fluid which means sCO2 power plants can be smaller, more efficient and not reliant on water for steam.”
Supercritical CO2 cycles can also operate using a wide range of heat sources.
“Their widespread implementation could be a game-changer for power generation applications in Australia,” Dr Harris said.
Supercritical CO2 turbines offer an autonomous, high-efficiency power cycle which does not rely on steam. This makes such turbines an ideal candidate for power generation in off-grid mining and remote operations, as it allows them to use renewable energy more efficiently to power their operations for longer periods of time.
“With many mining companies committing to large renewable energy targets, the use of sCO2 power could be the transformational technology that they are looking for,” Dr Harris commented.
CSIRO’s involvement in the partnership will improve understanding of how sCO2 power plants can enable lower- and zero-emission technology solutions, and how those plants might be used in remote mining and community locations as a low-cost alternative to diesel fuel power generation.
Of particular interest is how concentrated solar thermal (CST) technologies could be used to provide renewable energy for these sCO2 power plants.
CST technologies capture and store heat, which make it an ideal solution.
The Australian Solar Thermal Research Institute (ASTRI) which is a consortium of CSIRO and six Australian universities, is leading efforts in this area.
“The use of Thermal Energy Storage (TES) to provide the heat to run these turbines is a critical enabler for renewable energy solutions,” Chief Technical Officer of ASTRI, Wes Stein, said.
CSIRO is working with Graphite Energy, a highly innovative Australian TES company, on the use of portable and scalable TES units that can be used to store heat to run a sCO2 power plant.
“The use of sCO2 power blocks with our TES units will allow us to deliver the lowest-cost renewable energy solution currently available in the Australian market,” Graphite Energy CEO, Peter Lemmich, commented.
The STEP Project demonstration plant has been built in San Antonio Texas at SouthWest Research Institute (SwRI), and equipment installation is underway. It is expected to be operational in mid-2021.
