Making a rather clean fuel even cleaner: Natural gas + Biogas
According to a recent study by the Schweizerische Eidgenössische Technische Hochschule (EMPA, roughly translated as Swiss Federal Technical University), the best biofuel in terms of CO2 balance is biogas. Not a new thing for our readers, but their study shows that it reduces up to 90 percent of CO2 emissions from the tailpipe.
Biogas comes from fermentation of manure and waste and can be used directly into CNG (Compressed Natural Gas) without further modifications in the engine. Therefore it's a very good candidate to be used on its own or even mixed with natural gas as other biofuels are blended to their fossil counterparts.
The study also shows that biogas, even made artificially, saves the side effects of harvesting conventional biofuels, such as ethanol or oil for biodiesel. Using harvested vegetable raw materials, the global CO2 emissions could be reduced from 30 to 50 percent. In case of wood, these savings could be even better, topping 70 percent.
Blending biogas with conventional CNG seems a good solution. Some experts affirm that in 2030, a tenth of Germany's natural gas will be biogas but this study affirms that this number can be improved: it's possible to mix 10 percent by 2010 and 20 percent in 2020.
Taking in consideration the savings of CO2 emissions mentioned above, CNG vehicles can emit less CO2. For instance, an Opel Zafira 1.6 CNG which usually produces 136 g/Km CO2 could be lowered to 113 g/Km CO2 by using a 20 percent biogas mix. Add this to the fact that CNG already reduces NOx emissions 70 percent in front of conventional diesel engines and produces almost no particullates.
Related:
- Biomethane mixed with natural gas or diesel to make heavy vehicles greener
- University of Georgia and Mexico to partner on biofuels from dung
- Driving around Europe with Natural Gas: VW Touran, Fiat Panda and more
Reader Comments (Page 1 of 1)
amanbulls 6:24AM (10/24/2009)
Can you please answer my question ?
That how can we remove Hydrozen Sulphide from the composition of the Biogas.
To make it better for CNG Engines
Waiting for your reply
Thanks
AMAN SHARMA ( INDIA)
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A.Brien 11:43PM (7/31/2007)
And if they put hydrogen gas instead of 20% biogas mix what will be the co2/km ?
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Joseph 1:17AM (8/01/2007)
Brein, it will be more CO2 for hydrogen.
Of course you could say if the hydrogen is made from renewable electricity, but since hydrogen is less efficient it will take more electricity, So it could be clean, but it's wasteful.
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Manu Sharma 3:58AM (8/01/2007)
Biogas is absolutely the best fuel source for cars. I'm really surprised that it's not very popular because you can produce biogas in your backyard (as long as you have enough organic matter to feed it). A 2005 study found a biogas run Fiat Plunto to be 12 times better than a Prius.
http://www.ngvglobal.com/technology/biogas-natural-gas-vehicles-best-environmental-cars-2005-in-s.html
That said, I'm not sure that it can be used in CNG engines without any modification. There are a lot of CNG vehicles here in India and a many biogas plants. I've never heard of a CNG vehicle using biogas. I read somewhere that biogas contains Hydrogen Sulphide which must be filtered out to prevent engine corrosion. It also has excess CO2 which should be removed to lower the calorific value.
If CNG vehicles can be modified economically to accept biogas, it can become a very attractive fuel source for countries like India. It has both economics (almost free) as well as low emissions (lower than even the air car) on its side.
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Dugal Harcourt 4:10PM (10/31/2007)
I am from NZ & have invented an internal combustion engine the is simple, produces a minimum power output of 30-40% more HP and some 15 times more tourque outputs.Has been tested and has proven power outputs. Is able to be converted into a Hydraulic motor
Ideal for all forms of Land sea and air transport + mining, agriculture and industery. Has the abilits to convert Bio Gas into Electricity efficiently. Is pantents for Canada-China-Korea-Mexico-USA-NZ- others pending: Regards Dugal Harcourt (X! farmer)
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