A new high-efficiency small-scale solid oxide fuel cell system could be a key component for localized power generation, powering anything from entire neighborhoods to individual houses with methane.
According to a study in the Journal of Power Sources, the new fuel cell system can achieve up to 57% efficiency, beating out previously reported efficiencies from other solid oxide fuel cell systems of the same size, by using 'microchannel technology' and external steam reforming and fuel recycling. The system, developed at the Department of Energy's Pacific Northwest National Laboratory includes the use of fuel cell stacks which were developed earlier through the DOE's Solid State Energy Conversion Alliance.
"Solid oxide fuels cells are a promising technology for providing clean, efficient energy. But, until now, most people have focused on larger systems that produce 1 megawatt of power or more and can replace traditional power plants. However, this research shows that smaller solid oxide fuel cells that generate between 1 and 100 kilowatts of power are a viable option for highly efficient, localized power generation." - Vincent Sprenkle, paper co-author and chief engineer of PNNL's solid oxide fuel cell development program
A pilot program has been built with the new system, which can generate about 2 kW of electricity, or the equivalent in power that a typical American home consumes. The team working on the new solid oxide fuel cell system designed it to be capable of being scaled up to produce anywhere from 100 to 250 kW, which could power about 50 to 100 average homes in the U.S..
Why is it desirable to produce power on a smaller scale? Because smaller systems have a distinct advantage over larger ones, as a lot of the electricity produced by large systems needs to be sent through transmission lines, which leads to some losses. Smaller-scale systems are also physically smaller in size, so they can be installed closer to the users of the power, meaning that the electricity doesn't have to be transmitted as far. Those advantages make these smaller power systems ideal for 'distributed generation', or generating electricity in smaller amounts for local use.