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Early comprehensive life cycle assessments (LCA's) that compared biofuels with fossil fuels already appeared in the beginning of the eighties. Since then the public, scientific and political interest in biofuels has continuously grown and the number of biofuels and assessed parameters has increased.At the same time, the methodology for this type of assessment has improved with certain aspects of the approach having come up by and by a process which still continues today. Several issues related to the land use currently stand in the centre of expert discussions. Keywords: Environmental assessment; Biofuels; Transport; Land use assessment; Fossil fuels Article Outline 1. Objective, scope and background 2. Procedure 3. Results: comparison of biofuels and fossil fuels 3.1. Biofuels from agriculture compared to fossil fuels and against each other 3.2. Biofuels from residues compared to fossil fuels and against each other 4. Results: land use aspects 5. Conclusions and outlook 5.1. Competing land use 5.2. Competing biomass usages

Despite increasing green awareness and steadily rising gasoline prices, Americans and other denizens of the developed world - not to mention millions of new Chinese and Indian drivers hitting the road every week - are loath to give up the freedom and privacy of their personal automobiles. But snarled traffic, longer commute times, and rising pollution levels have given city transportation planners new ammunition in their efforts to encourage the use of clean, energy-efficient public transit. One of the newest tools in their arsenal is so-called congestion pricing (also called variable toll pricing), whereby cars and trucks are hit with higher tolls if they access central urban areas at traditionally congested times.

The lithium ion car battery created by Tesla Motors has passed a battery of certification tests that effectively remove another hurdle in the path toward selling products. Because they can burst into flames, lithium ion batteries are classified as dangerous goods, according to Erik Toomre, Director of Manufacturing Programs. "Before we ship it to the public, we have to demonstrate that it is safe," he said.

The lithium ion car battery created by Tesla Motors has passed a battery of certification tests that effectively remove another hurdle in the path toward selling products. Because they can burst into flames, lithium ion batteries are classified as dangerous goods, according to Erik Toomre, Director of Manufacturing Programs. "Before we ship it to the public, we have to demonstrate that it is safe," he said.

According to a recent BBC feature, the impact of increasing the cost filling up from 15-20$ to 70-80$ are dramatic. The market for second hand SUV's has collapsed, real-estate in the outer suburbs looses value at a rate of 4,000$ per additional minute commuting time and the use of public transportation sees a marked increase.

REGENERATIVE BRAKING is widely practised, but there have to be other trains around to absorb the surplus power being fed back into the catenary or third rail. Processing the output from trains and pushing it back into the local grid is possible with an AC power supply, but very expensive with DC traction. Too often, power produced by traction motors in braking mode ends up heating resistor banks. The elegant alternative is to store the braking energy on the train. This not only avoids the electrical complications of regenerating through the traction power supply network. It reduces the rated power requirement of that network by lopping demand peaks during acceleration, saves energy by reducing losses in the catenary or conductor rail, and by limiting voltage drop it allows substations to be further apart. NiMH batteries have the necessary energy storage density in terms of kWh/kg, and are slightly more expensive, but their life in terms of charge/discharge cycles in no way matches the LRV requirement for 2million cycles over 10 years. Flywheels have been tried but never caught on for several reasons.

Created by environmental psychologist Doug McKenzie-Mohr this site consists of five resources for those working to foster sustainable behaviors, such as those involved in conservation, energy efficiency, transportation, waste reduction, and water efficiency. The site includes the complete contents of the book, Fostering Sustainable Behavior, as well as searchable databases of articles, case studies, and turnkey strategies. Further, it includes, discussion forums for sharing information and asking questions of others.