Understanding environmental impact of alternative vehicle fuels

Gasoline and diesel are no longer the only viable fuels for bakery and snack trucks. Alternative fuels for both route and over-the-road trucks are becoming mainstream in the marketplace. Regional availability is still a controlling factor. However, given the lifetime of a truck, good long-term planning requires continuous attention to the developments in fuel alternatives and availability. In the background is the increasing attention of the government to write rules that address the issue of climate change and impact vehicle specifications and company air emission limits.

Low sulfur clean-burning diesel trucks are replacing gasoline trucks. But diesel and gasoline fuels are of environmental concern because burning the fuel emits carbon dioxide, nitrous oxide and methane. Alternative fuels are meant to reduce greenhouse gases, which include water vapor, carbon dioxide, methane, nitrous oxide and ozone.

Alternative fuels include hydrogen, biodiesel (B20 and above), ethanol (E85), electric, compressed natural gas (CNG), liquefied natural gas (LNG) and liquefied petroleum gas (propane).

There are more than 14,765 public alternative fuel stations in the continental United States. There are thousands of private stations. For example, companies that use propane often install their own fueling station.The most common comment about hydrogen fuel is that, “it will always be the fuel of the future.”

Biodiesel B20 is a vegetable oil or animal fat-based fuel. Biodiesel may be blended with petro diesel in any proportions. Biodiesel is used in standard diesel engines. Availability, maintenance issues and weather-complicated starts have limited adoption of this fuel. Vigilant maintenance is required to avoid an increase in emissions of carbon monoxide, carbon dioxide and nitrous oxide.hE85 is an 85% ethanol and 15% gasoline or other hydrocarbon by volume. The fuel is produced from cellulosic fiber such as corn leaves, stalks and husks. Although some tail-pipe emissions are reduced, the fuel increases the emissions of acetaldehyde, a toxic chemical. Maintenance and operational issues have been identified. Studies have shown that the toll on the environment of current corn production for ethanol production has been serious, draining water supplies and degrading soils.

Electric road vehicles are powered by an on-board rechargeable electricity storage system and a direct continuous connection to land-based generation plants for purposes of on-highway recharging with unrestricted highway range (urban mass transit) or an on-board rechargeable electricity storage system and a fueled propulsion power source (internal combustion engine): plug-in hybrid.

The environmental impact of using energy generated by a coal-fired power plant is the biggest off-set to any environmental benefits of running these vehicles. Up scaling vehicles for the transport of commercial goods has been problematic.A natural gas vehicle uses compressed natural gas (CNG) or liquefied natural gas (LNG). Most natural gas vehicles are buses. Fueling stations are mostly regional. Cold weather and maintenance issues have been concerns. The burning of natural gas produces lower carbon emissions than gasoline or diesel fuels.

According to a study funded by the Propane Council, at the point of use, propane emits fewer greenhouse gases than gasoline, diesel, heavy fuel oil or E85 ethanol per unit of energy. Natural gas (methane) generates fewer greenhouse gas emissions per British thermal unit than propane, but methane is chemically stable when released into the air and produces a global warming effect 25 times that of carbon dioxide. Propane is a good choice from an environmental perspective and also is an economically viable choice at this point in time.

Route scheduling is becoming increasing sophisticated with software that may add fueling stations as a variable. Trucks are better designed for weight and aerodynamics. Vehicle refrigeration systems are improving. All these changes will increase efficiencies in the face of increasing vehicle costs.

States are required by the Environmental Protection Agency to reduce their carbon emissions and to meet the goals; some may convert their fleets to alternative fuels, thus encouraging more fueling stations.

Reference 

1. www.afdc.energy.gov 

2.www.epa.gov/smartway 

3.www.fueleconomy.gov/feg/SmartWay.do.