Algae could be the basis for a new green form of oil; one that absorbs more carbon dioxide than it creates, and can be used in existing vehicles. Algae grows extremely quickly, feeding on CO2, and according to Spanish company Bio Fuel Systems, can produce 400 times more oil per hectare than traditional biofuels such as soybean or palm oil. Russell Beard visits the company’s plant in Alicante, where engineers at a test site are using waste CO2 from a neighbouring cement factory to feed hundreds of huge tubes of algae and produce five to ten barrels of carbon-negative oil per hectare per day. Early results have been so successful that they now plan to open a 600 hectare site in arid southern Spain, with the aim of producing algae-based oil on an industrial scale.

Belize is proud to have the largest barrier reef in the northern hemisphere, but in 2010 the tiny country was facing a huge problem – the potential loss of the reef's UNESCO World Heritage Site status. The reef's species were being depleted by bottom-dragging fish trawler, jeopardising a major source of revenue from tourism. Local fishermen also complained they were being prevented from making a living by what many critics call the maritime equivalent of strip mining or clear-cut logging. Belize decided to take a stand, becoming one of the world’s first nations to ban trawlers from all its waters. Sharita Hutton travels to Belize to find out more about the ban.

Sources of renewable energy can be found in unexpected places, and one of the less well-known processes currently being researched is the generation of osmotic power, or salinity gradient power. This describes the energy available from the difference in salt concentration between two bodies of water, for example a river and an ocean. Osmotic power is explained in this week’s ‘How It Works’ animation.

Shipping is one of the fastest growing and most heavily polluting industries. Shipping fuel releases ultra-fine soot particles which pose health threats, as well as various global warming pollutants including black carbon from incomplete fuel combustion, nitrogen oxides, nitrous oxide and of course CO2. Tûranor, the world’s largest solar-powered sea vessel, aims to provide a viable alternative using materials and technology that are already available – and becoming cheaper all the time. earthrise’s Oliver Steeds boards Tûranor during its recent bid to become the first entirely “solar” boat to circumnavigate the globe.

 
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Source: Al Jazeera