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Issue 11
, 2009
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Riding on biogas

Biomethane emerging as a car fuel option
Source: Toxics Alert, Date: , 2009

car Biogas or renewable natural gas is the name given to the mixture of methane and carbon dioxide gases that is formed whenever organic materials decompose in the absence of air, a process known as anaerobic digestion.When this happens in nature the gases escape into atmosphere and harm the climate.However,this process can be managed in an industrial plant under controlled

Methane is about 20 times more harmful to atmosphere than carbon dioxide as greenhouse gas.Thus by capturing the methane and preventing it from becoming a GHG is good for environment.

Biogas can be manufactured from almost any organic material but historically it has been produced from sewage sludge and animal slurries. At present energy crops such as grass maize and household waste are used for its production.Biogas can be used as a vehicle fuel. For this,Carbon dioxide and hydrogen sulphide need to be removed. The former ,because it compromises the operating range of the vehicle since it does not burn, and the latter due to its corrosive nature.Biogas for automotive application is called biomethane.Methane within biogas can be concentrated via a biogas upgrader to the same standards as fossil natural gas; when it is, it is called biomethane.

Biogas can be utilized for electricity production on sewage works , cooking, space heating, water heating and process heating.

If the local gas network permits it the producer of the biogas may be able to utilize the local gas distribution networks. Gas must be very clean to reach pipeline quality, and must be of the correct composition for the local distribution network to accept. Carbon dioxide, Water, hydrogen sulfide and particulates must be removed if present. If concentrated and compressed it can also be used in vehicle transportation. Compressed biogas is becoming widely used in Sweden, Switzerland and Germany. A biogas-powered train has been in service in Sweden since 2005.

biogas trainAs per BBC news published on June 20 , 2005, "The train, fitted with two biogas bus engines, can carry up to 54 passengers, and will run on Sweden's east coast between Linkoeping and Vaestervik.Biogas, produced by decomposing organic material, emits far less carbon dioxide than traditional fossil fuels.The train can run for 600km (372 miles) before it needs to refuel and can reach 130km/h (80mph).Sweden already has 779 biogas buses and thousands of cars running on a mixture of petrol and either biogas or natural gas."

Bates, an inventor, lived in Devon, UK, modified his car to run on biogas. A short documentary film called 'Sweet as a Nut' in 1974, talks through the simple process and benefits of running a car on biogas, at which point he had run his car for 17 years on gas he had produced by processing pig manure.

Inspired by real life innovations in automobile fuelage , environmentally friendlier cars are now crashing on the Fox series “24.”

To be fair to one and all,Fox is not the first network to tout its devotion to the planet. In November NBC Universal committed to “greening” three shows, including the “Nightly News With Brian Williams” and “Saturday Night Live,” by using alternative fuels and increasing recycling and composting,reports New York Times. Warner Brothers and Disney also have environmental divisions.

As per media reports and information from Fox's own den figuring out how to reduce carbon-dioxide emissions on a show that often shoots on location and is known for explosion-enhanced action was not easy.Reports reveal that the first step in this green initiative was to evaluate how much of the greenhouse gas was produced, examining everything from the cars used to ferry scripts across the Los Angeles area to flights taken by actors and executives. Two categories accounted for 95 percent of emissions: fuel for on-site generators, transportation and special effects; and the electricity used for sets and offices.

The cast, crew shared scripts electronically and drove around in hybrid vehicles( to learn more about hybrid vehicles scroll down till baseline), eliminating the use of 1,300 gallons of gasoline, reports Fox. But challenges galore. The effect of carbon offsets is hard to evaluate.Although it is possible to replace the hot, energy-consuming floodlights that studios use with lights using CFL technology, the quality of the light gets compromised, not keeping with the exacting exacting production standards.

The media network hired consultants to measure the carbon-dioxide output from the production, started using 20 percent biodiesel fuel in trucks and generators, installed motion monitors in bathrooms and kitchens to make the lights more efficient and paid the higher fees that help California utilities buy wind and solar power.

Car crashes posed a bigger problem since even hybrid vehicles emit carbon dioxide when blown up. The option of going ahead without chase scenes or "outdoor" would have dissatisfied Fox's viewers.Supporting green causes does not , for most of the viewers, translate into having mundane or unexciting shows. Fox had to find a way out.The way-out came in the form of carbon offsets.

The producers of "24" decided to settle for buying carbon offsets, which in theory make up for emissions of carbon dioxide, the main heat-trapping gas linked to global warming, by paying other people to generate enough clean energy to compensate — in this case wind-power plants in India.

The producers said they bought enough credits to offset only just over a half-season’s worth of emissions.

Not a bad start on the energy freeway!
  • What are hybrid vehicles?
A hybrid vehicle is a vehicle that uses two or more distinct power sources to move the vehicle In addition to vehicles that use two or more different devices for propulsion, some also consider vehicles that use distinct energy sources or input types ("fuels") using the same engine to be hybrids, although to avoid confusion with hybrids as described above and to use correctly the terms, these are perhaps more correctly described as dual mode vehicles.

Power sources include:

* On-board or out-board rechargeable energy storage system (RESS)
* Gasoline or Diesel fuel
* Hydrogen
* Compressed air
* Human powered e.g. pedaling or rowing
* Wind
* Compressed or liquefied natural gas
* Solar
* Coal, wood or other solid combustibles
Vehicle type:
  • Two-wheeled and cycle-type vehicles
  • Heavy vehicles
  • Rail transport
  • Road Transport, Commercial Vehicles
  • Ships
Fuel consumption and emissions reductions

The hybrid vehicle typically achieves greater fuel economy and lower emissions than conventional internal combustion engine vehicles (ICEVs), resulting in fewer emissions being generated. These savings are primarily achieved by three elements of a typical hybrid design:

1. relying on both the gasoline (or diesel engine) and the electric motors for peak power needs resulting in a smaller gasoline or diesel engine sized more for average usage rather than peak power usage.
2. having significant battery storage capacity to store and reuse recaptured energy, especially in stop-and-go traffic.
3. recapturing significant amounts of energy normally wasted during braking etc. (regenerative braking)

Other techniques that are not necessarily 'hybrid' features, but that are frequently found fuel saving measures on hybrid vehicles include shutting down the gasoline or diesel engine during traffic stops or while coasting or other idle periods .

Hybrid Vehicle Emissions

Hybrid Vehicle emissions today are getting close to or even lower than the recommended level set by the EPA (Environmental Protection Agency). The recommended levels they suggest for a typical passenger vehicle should be equated to 5.5 metric tons of carbon dioxide.

Environmental impact of hybrid car battery

Though hybrid cars take in substantially less petroleum than conventional cars, there is still an issue regarding the environmental damage of the Hybrid car battery. Today most Hybrid car batteries are one of two types: (1) nickel metal hydride, or (2) lithium ion; both are regarded as more environmentally friendly than lead-based batteries.