New Energy and Fuel blog posted an article about a fascinating new technology: geothermic fuel cells (GFC) for extracting unconventional hydrocarbons such as kerogen. The technology is being developed by Independent Energy Partners.
There are enormous deposits of gas and oil around that world that are imprisoned in chemical and physical states that make extraction uneconomical. New technologies can make such deposits economical such as we have witnessed with the explosion of fracking and horizontal drilling in shale formations in the US and Canada. Formations with kerogen are abundant, but there has not been a way to extract the gas and oil in a profitable manner. Kerogen needs to be heated in order for hydrocarbons to be available for extraction. This presents obvious problems, as any process that requires heat requires energy input that adds to costs.
Geothermic fuel cells use a very clever positive feedback loop to obtain the necessary heat to induce hydrocarbon flows in the kerogen formations such that extraction becomes economical. An initial external source of natural gas (methane) is used to power stacks of fuel cells embedded in boreholes in a given kerogen formation. The fuel cells generate heat and electricity. The electricity can be used to power onsite equipment and excess can be sold to the grid. The heat causes oil and gas to flow which can be extracted in nearby wells. Most of this can then be sold to refineries, but a little of the gas can be siphoned off to power the fuel cells. Thus, after start up, the system forms a closed, positive, feedback loop.
Here is a description from Independent Energy Partners: “IEP’s proprietary approach to geothermics presents a revolutionary option to the unconventional hydrocarbon industry. Our system leapfrogs the current burner and electric ground heating technology by placing a high-temperature fuel cell stack within a formation to heat the ground. As the ground is heated, hydrocarbon liquids and gases are released from the resource into neighboring collection wells. A portion of the gases are processed and returned to the fuel cell stack, with the remainder available for sale into the energy markets.
After an initial warm up period in which the cells are fueled with an external source of fuel, the GFC self-fuels from gases created by its own waste heat. This self-fueling system, in steady-state operation, produces oil, electricity and surplus natural gases. The result is a geothermic heater that is designed to produce a Net Energy Ratio (NER) of approximately 7.0 (i.e., 7 units of energy produced for every unit used). The net energy ratio of GFCs will increase to approximately 18.0 when primary recovery is combined with residual char gasification and resulting synthesis gas.”
New Energy and Fuel blog has links to the patent and a video. All can be read here.