According to new research by Jesse Ausubel at the Rockefeller University in New York, renewable energy sources could wreck the environment. The research looked into how much land it would take to generate electricity from renewable sources to make a large difference in global energy demands and concluded that building enough wind farms, damming enough rivers and growing enough biomass would mean a huge invasion of nature.

The results are startling – to meet the 2005 US electricity demand, an area the size of Texas would need to be covered in wind turbines, running 24/7. New York would need a wind farm the size of Connecticut to meet it’s demand for electricity. To put this into more perspective – biomass and wind farms produce around one or two watts per square metre.

Researchers at the New Jersey Institute of Technology have developed a do-it-yourself version of the solar panel. Their research focuses on inexpensive solar cells that can be printed on some computer printers or painted onto plastic sheets to create instant solar panels.

At present, renewable energy for the home tends to be quite expensive and needs to be installed for many years before it the savings outweigh the installation costs. Developing a cheap solution to the renewable energy market would be a goldmine. Purified silicon is used in most solar panels and this is too expensive for most consumers. Instead, researchers have concentrated on polymer-based materials which is a much cheaper option.

Alcatraz is one of the world’s most famous prisons. Once a home to murderers and mobsters, Alcatraz is transforming itself into an eco-paradise.

Alcatraz shut it’s doors to prisoners in 1963 however hundreds of people still visit the prison, making it one of San Francisco’s top tourist attractions. All the tourists mean the former prison still has large energy needs, something which Alcatraz itself cannot provide. The facility’s fuel, water and waste is transported backwards and forwards every day across the bay.

According to some scientists, harnessing the tidal power in Pentland Firth could provide as much energy as a nuclear power station. Once described as the “greatest untapped source of energy Scotland has ever had”, the Pentland Firth has always been considered too deep and too dangerous to exploit. However, with research showing that tapping into it could see electricity production that could fuel every home and business in Scotland several times over, the race is on to harness this power.

Aside from electricity production for properties, it is envisaged that any spare electricity produced could be used to convert rubbish into biofuel, helping solve the problem of our oil dependency and over-reliance on landfill sites.

Waverollers are a way of harnessing the power of the oceans. The power they produce is renewable and green and their grids are easily scaleable. Their simplicity and relatively cheap costs look as though these could be one of the best ways to harness renewable energy souces in the future.

In surface waves or swell, water particles roll in a circular otion. As the waves come in towards the shore, the energy is squeezed by reducing depth. Below the swell at the surface, the circular motion ends up being more elliptical than circular and at the bottom of the sea, the water particles rock backwards and forwards up to the breaker line. This phenomenon is known as ‘bottom waves’. These bottom waves tend to be a lot more continuous and predictable than the wind meaning harnessing these waves would be fantastic for predictable renewable energy production.

A Chinese farmer in Quqiao village has constructed his own solar power water heater - out of beer bottles and hosepipes. He built the solar panel to help heat up water in his home. “I invented this for my mother,” Ma Yanjun explained. “I wanted her to shower comfortably.”

The solar panel is constructed from 66 beer bottles attached to a board. Each bottle is interconnected so that the water flows through the bottle network. As the water flows through the bottles, the sun heats it up. At the end of the network, the water is piped into the bathroom where it emerges as hot water.

Wind Turbines are a great way of producing electricity from a renewable source as they do not produce any emissions. However, there are questions over whether wind turbines are really worth it. One of the world’s windiest advanced nations, the UK, already has over 1,600 wind turbines attached to it’s national electricity grid.

According the the UK’s National Grid though, in the five month period between the start of October 2006 and the end of February 2007, at a time when there should be plenty of wind around, there were 17 days when output was less than ten percent of capacity. Delving deeper, the figures show that in five days during the period, output was less than five percent, and on one poor day, output was just two percent of capacity. Over the entire five month period, the wind turbines averaged a poor 35% efficiency overall.