The second phase in the evolutionary development of coal is lignite. Lignite is found in great quantities in the Western part of this country. Again lignite is not particularly efficient in producing energy per mass of fuel. There have been quite a bit of effort recently in the liquification and gasification of lignite. Liquification converts lignite into liquid crude petroleum.
Gasification plants convert lignite into natural gas products.
The conversion process is quite expensive, and with the present cost of other forms of fuel, it is economically infeasible. However, if other fuels become too expensive, this could be a more economical process. Other research has been conducted by the Bureau of Mines in North Dakota investigating other uses of lignite such as a fertilizer in hydroponic plant growth. Hydroponics is the use of neutrient containing water instead of soil in the growth of plant life. These last two phases are very prevalent in the Northern and Eastern parts of the country.