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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

To wrap up my ode to John Henry (and a more sustainable lifestyle) I am going to cover a few more everyday household plug-ins by giving the current ON the grid offering, it's OFF the grid alternative, and weigh in on whether a switch is warranted.

Electric Car Conversion Kits are equipments and components that can be used to convert a Gas Powered Car to Electric. There are a few different types - AC kits, DC kits, custom kits, universal kits etc - the kits you end up using will depend on your budget, and your need. Once you build your Own Electric Car you will completely eliminate Gas cost and never pay for gas again, Qualify for up to $1000 IRS refund for driving a clean fuel vehicle. Electric car kits vary in cost depending on make and quality and can be quite expensive. This lens looks into how you can put your own electric car conversion kit together and use it to build your electric car thus avoiding the high cost of of electric car conversion kits or buying a new elctric car.

Does SolarWorld, after Hillsboro, make a habit of buying up plants in trouble for a song, or does it genuinely want to move into cars?

Batteries have to contain all of the chemicals on both sides of their energy releasing equation. The very best batteries available today can store about 0.4 MJ/kg (0.05 kw-hr/lb) including the cases and safety systems. In contrast, gasoline carries about 46 MJ/kg (5.7 kw-hrs/lb).\n\nEven with a 20% efficient IC engine, a gasoline tank stores 20 times as much energy as a battery of equal weight. As the vehicle is moving it gets rid of some of that weight. Battery powered vehicles must carry the full weight of their energy source.\n\nThe energy density difference also plays a key role in the time that it takes to put more energy back on the vehicle once a fuel load is consumed. A two minute fill-up of a 12 gallon tank puts the equivalent of 87 kilowatt-hours into the vehicle, again, taking into account the 20% thermal efficiency.\n\n87 kilowatt-hours in 2 minutes works out to 2.6 MegaWatts. Even with a 220 volt connection, that would require about 11,800 amperes of current. Just imagine the size of the electric cables for that current.\n\nThere are certainly places and applications where electric vehicles have a role, but it is worth remembering that at least five or six generations of engineers have looked very hard at trying to meet transportation needs and they keep coming back to the same fact - when you want to move a vehicle, you need power, (energy per unit time).

The National Science Teachers Association (NSTA) has teamed up with Discovery and the Siemens Foundation to launch a new initiative called the "Siemens We Can Change the World Challenge." The initiative calls on K-12 students to develop green solutions for their schools, homes, and communities. The initiative comprises several components, including introducing students to concepts in sustainability, educating students on environmental issues, building up STEM skills, and, eventually, connecting students with scientists to tackle environmental challenges through real-world projects.

Each federal government agency receiving recovery funds has set up a website which outlines how they plan to spend funds. This page has a link to each of these sites. This includes some interesting information from the department of energy.

In electrical applications, aluminum can do everything that copper can, but more efficiently and economically. Aluminum provides up to twice the conductivity per pound of copper (dependent on the specific alloy and application) at less than half the cost per pound (based upon current prices) for a 400% economic-efficiency advantage over copper.

Project Nova's innovative aerogenerator wind turbine is based on a pair of giant V-shaped composite wings that will be scaled up to 120m high and rotate around the central axis to create power. Invented by David Sharpe and developed by Wind Power Limited, the aim is for a large-scale demonstrator to be installed offshore within six years and for offshore vertical-axis turbines to provide 1GW of power by 2020.

We've been hearing that renewable energy is a fast-growing sector, and now it's official: The Energy Information Administration's (EIA) latest report found that renewable energy made up the biggest share in the U.S.'s electricity capacity increase in 2007. The huge wind power industry, not surprisingly, accounts for most of this increase. According to the EIA's Electrical Power Annual report:

This story is now repeated annually. And of course it is correct in capacity terms, but fails to recognise the relatively modest energy contribution for all this capacity. If one were to make the comparison in terms of GWh instead of GW, the picture would be totally different. If this goes on for a while, baseload electricity users, today's utilities' best friends, may become a sheer nuisance in the future.

World firsts are always interesting. Here, a bus network in Adelaide, Australia will operate using a solar photovoltaic system. Of course, the region has enough sun to keep energy levels topped up. In regard to using solar for other city systems, it will be interesting to see how this model works .

A timely article to remind readers about the status of wind turbines in the US. No longer a marginal form of electrical generation, wind turbine installed capacity in the US is on the up. Apparently, wind already supplies about 1% American electricity, powering the equivalent of 4.5 million homes. However, in spite of advances in the wind field, electricity generated via wind turbines is at this time costlier than that generated from fossil fuels. Also, wind power has the disadvantage of being intermittent and unpredictable, but this matter may be overcome with battery storage in some cases.

Well Benoit's idea of rainwater turbines may still be harebrained, but at least he's not the only one. And it could also be used for drainwater turbines.

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.

A further advance in energy technology is revealed - the great white hope it seems is salt. Only up to powering light bulbs so far, salt power for all is a distant prospect. The important point here is that, new concepts such as this, which are technological undercurrents, may one day rise to offer helpful energy solutions.

The European Commission is currently in the process of dreaming up an offshore wind power action plan and it's put a shout out for anyone with an opinion to come forward.

A vision... from the past... and the future...