MIT researchers have come up with a compromise that could help bridge the gap between well-established fuel sources and modern energy systems. They have developed a hybrid system that combines two common techniques: gasification and fuel cells. Lab experiments show that this new system could dramatically reduce operational costs and carbon emissions, make coal plants as much as 50 percent more efficient than they are today.
The trick is that the heat produced by the fuel cell would be used to make steam that supports the gasification process. Plus, both systems operate at similar temperatures, so there is minimal energy loss when they are combined. As steam passes through pulverized coal, it releases hydrogen and carbon monoxide gases, which then go into the fuel cell. Inside the fuel cell, the gaseous fuel reacts electrochemically with oxygen in the air to produce electricity.
While traditional power plants burn coal, which produces ash and other pollutants, the hybrid system produces much lower emissions because it doesn’t involve combustion. While the new system does produce carbon dioxide, is in a pure stream that doesn’t get mixed with the air. This would make it much easier to trap so that it can be properly disposed or even used to make batteries. “If we’re going to cut down on carbon dioxide emissions in the near term, the only way to realistically do that is to increase the efficiency of our fossil fuel plants,” says researcher Katherine Ong. The researchers described their work in a paper in the Journal of Power Sources.
