Methane, CH4, is the lightest (least dense) and simplest hydrocarbon. It is the major constituent of natural gas, and a potent greenhouse gas. It may be captured as biogas and refined to pure methane. Another route is to produce it artificially from hydrogen and co².
Production
Many biological processes produce it as it is a a byproduct of fermentation and composting. This method of production is called methanogenesis. The method hence does not use electricity at all, but in some cases this may also be a disadvantage is it then doesn't allow to store the electricity ie generated using PV-panels.
It can also be produced artificially using electricity (Sabatier process) This process basically combines CO² and hydrogen (H). See http://en.wikipedia.org/wiki/Sabatier_process This may be useful as although hydrogen can be made at home using electricity and is even in its current state a useful fuel, yet has many problems regarding the gas storage. Methane has fewer storage problems ? Besides using the Sabatier process to combine hydrogen made trough electrolysis of water (or from oxyhydrogen), it can also be made from biohydrogen.[1][2]
Advantages
- It can be used very easily for low pressure/relatively low heat uses, such as mantle lighting or cooking.
- It can be used as a vehicle fuel, yet then requires pressurisation (so a gas compressor needs to be added to the system[3][4]). It can be compressed to a specific pressure at which methane is still a gas (say 3600 psi for the tank/125psi injected to motor). It can also be compressed untill it becomes a liquid fuel; however at these pressures the fuel has actually consumed more energy for the compression than what it can actually release in work when combusted.[5]
Disadvantages
If allowed to escape it has a negative impact on the climate. This, as it's a very potent GHG-gas. It breaks down when burned, so not a problem if burned; yet it can be a problem ie in case of leaks. Although it is a potent greenhouse gas, it does not last as long in the atmosphere as many other such gases, eventually breaking down into carbon dioxide and water vapor.
Reflist
See also
External links
- Wikipedia:methane
- Methane digestor at EcoReality.
- ↑ Methane production using biohydrogen
- ↑ Methane generation using microorganisms being looked into by Cambrian Innovation for commercial use
- ↑ Biogas composed of 95 percent methane useful as vehicle fuel, can also be used in regular CNG systems
- ↑ Compressor used in very similar fuels, ie natural gas for transport
- ↑ [Journeytoforever on methane for vehicle use