Engineers from GE Global Research unveiled a turbine that could provide power for 10,000 homes. But what’s truly remarkable about this turbine is its potential to solve the world’s energy challenges.
Typically, turbines weigh tons and use steam to run—this one is no bigger than the size of your desk, weighs around 68 kg (150 pounds), and runs on carbon dioxide. “This compact machine will allow us to do amazing things,” said Doug Hofer, lead engineer on the project, in Albany, New York. He continues, “the world is seeking cleaner and more efficient ways to generate power. The concepts we are exploring with this machine are helping us address both.”
The current design of the turbine will allow up to 10,000 kilowatts of energy to be produced; however, researchers are looking into scaling up the technology so that it can generate up to 500 megawatts, which could be enough to power a city.
To work, carbon dioxide is kept under high heat and extreme pressure. Given these conditions, the carbon dioxide goes into a physical state somewhere in the middle of gas and liquid. The turbine then harnesses the energy, transferring half of the heat to become electricity.
The design also allows for easier operation—the turbine can be powered up and turned off easily making it more efficient for grid storage, a longstanding issue for other renewable energy sources such as solar and wind power.
The result is a turbine that can generate energy in a more efficient and sustainable manner.
According to GE, the power cycle is a closed loop, which means that the carbon dioxide circulates continuously, ensuring that there are no waste products. To break this down a bit more, the unit is driven by “supercritical carbon dioxide,” which is in a state that at very high pressure and up to 700 °C (1290 °F). And notably, once the carbon dioxide passes through the turbine, it is cooled and then repressurized before returning for another pass.
As MIT notes in the release, “Steam-based systems are typically in the mid-40 percent range; the improvement is achieved because of the better heat-transfer properties and reduced need for compression in a system that uses supercritical carbon dioxide compared to one that uses steam. The GE prototype is 10 megawatts, but the company hopes to scale it to 33 megawatts.”
Also of note, a steam system can often take 30 minutes to get working; however, a carbon dioxide turbine might take only a minute or two.
Currently, the team is coordinating with various US government agencies to test the turbines.