The use of fossil fuels such as lignite causes massive CO2 emissions that are polluting the atmosphere. The carbon contained in the coal was formed millions of years ago from plants that were converted into coal deposits under great pressure and high temperature deep down inside the earth. Plants growing today, on the other hand, release, when burned, only the amount of CO2 which they have previously absorbed from the air, so that a carbon neutral balance is maintained. The Swiss company AVA-CO2 is taking advantage of this fact by producing coal from organic residues – within just a few hours. They developed an economically viable technology based on Hydrothermal Carbonization (HTC). What is special about it, is, that moist organic material can be used energy efficiently without being pre-dried. By the way, HTC was originally researched and described by Friedrich Bergius in 1913.
http://explore-house.eu/en/2014/10/01/hydrothermal-carbonization-ava-co2/
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