Today’s world faces a large problem which is global warming. Glaciers melting see, and oceans water level rising, and droughts in Africa. According to [1] there are seven main sources of CO2 emissions from fossil fuels combustion: 1. Solid fuels (e.g. coal) – 35% of CO2 emission 2. Liquid fuels (e.g. gasoline, fuel oil) – 36% of CO2 emission 3. Gaseous fuels (e.g. natural gas) – 20% of CO2 emission 4. Flaring gas industrially and at wells: <1% of CO2 emission 5. Cement production: 3% of CO2 emission 6. Non-fuel hydrocarbons: < 1% of CO2 emission 7. The "international bunkers" of shipping and air transport not included in national inventories: 4% of CO2 emission As one can see from the list above, natural gas, which is mainly used for space heating in Europe, is responsible for 20% of total CO2 emission. Because of this fact limitation in using of this fossil fuel is an important issue.