Luca Technologies started up a project to produce natural gas from coal. The idea is to use microorganisms inside the coal layers of Earth to change coal into methane. The gas can in this manner be pumped out to be used in various processes known today. The method is environmental friendly if we consider that gas produces only half of the CO2 that coal does. Besides this, the method is very economic as 0.01% of US coal can produce the current annual natural-gas demands.
For investigations and process start-up, the company raised about $76 million. Altruda Energy Corporation, founded by Andrew Scott, former professor of economic geology at The University of Texas, Austin, is developing a similar process. Natural gas is the product of heat and pressure in millions of years, but Andrew Scott showed that a small quantity of natural gas is being produced by microorganisms that feed on coal. One type of microbes break the long hydrocarbon molecules into shorter molecules, and another type of microbes convert these molecules into organic acids and alcohols. Microbes called methanogens feed on these organic acids and alcohols to produce methane.
Research at Luca Technologies proved that the amount of methane can be increased by adding the correct nutrients. The fact was very difficult to be implemented as inside coal beds there are a lot of microbes, some being able to interact with the methane production. But the right nutrients were found to favor methane producing organisms. In US many wells were drilled to collect natural gas from coal beds but production stopped because there were not profitable anymore. After the treatment, most of these wells became again profitable and production increased considerable.
Luca Technologies will continue research to understand better how the entire process works and how the microbes can increase the production of methane.
This method will be used in most of the US wells to increase production of methane and extend the lifetime of natural gas wells. Conventional techniques to extract methane from coal beds kill the microbes responsible for methane production by removing the water needed and by introducing in their life habitat oxygen. These 2 factors kill the microbes and the gas production stops. If the conditions are strictly maintained the microbes can continue to digest coal and produce methane.
Luca Technologies could also use their techniques to collect useful fuel from coal that’s inaccessible to conventional mining.
In this moment no one knows how much of the coal beds can be used to be converted into methane, considering the nature of the beds, how much waste the microbes produce from which they could die off, and the reaction of humans. Most of the coal beds are source of drinking water, and even if the microbes are not harmful to human there could be some hostility against using them in some areas.
The success of the method depends on the costs of the research and implementation and also on the price of natural gas. Still, this could be a good process to reduce the CO2 emissions to half compared with normal coal usage.