WIND FARMS LOOKING UP OFFSHORE: A boat sails through a wind farm off the southeastern coast of England. The world’s first deepwater floating wind turbine is set to be built off Norway’s coast next year, Norwegian oil company StatoilHydro announced on May 22. Offshore wind turbines already exist in numerous places around the world but they have all been stationary turbines planted on the bottom of the seabed. StatoilHydro plans to attach the floating turbine to the top of a buoy, using technology similar to that of offshore oil and gas platforms. It has several advantages over a stationary turbine – it can be placed in far deeper waters, where winds are often stronger, and it can be moved. StatoilHydro is investing $80 million in the test project, which will tower some 65 meters above the waves and have a capacity of 2.3 megawatts.
In Cambodia’s rural hinterlands, reliable and affordable electricity from the national grid is a pipedream. The government has pledged to electrify the whole of the Kingdom by 2021 but in the meantime power-hungry farmers are getting creative.
Diesel generators, car batteries, kerosene lamps and candles are all widely used in rural areas as alternatives to electricity, yet such methods of powering up are expensive.
“In urban areas we now have reliable and affordable electricity but in the rural areas they do not,” said Sat Samy, minister in charge of alternative energy. “[Farmers] have no money and no electricity but they need it more than we do in the towns.”
A move is afoot to show farmers how to turn something they have in abundance – animal manure – into something they desperately need: electricity. Step forward the humble biodigester, a simple contraption that turns pooh into power.
“You need 30 to 40 kilograms of manure per day to get around 1,200 liters of gas, which is enough to run all normal household appliances – electric cooker, lamps – for a day,” said Son Mao, a manager and technician for the biodigester project of the Cambodian Rural Development Team (CRDT), a local NGO.
A biodigester is a system of closed containers – either plastic or cement – that help decompose the micro and macro organisms in manure through a fermentation process to produce biogas and slurry.
The technology is simple but effective: one kilo of manure creates approximately 40 liters of gas. This is more than enough for the average family, according to Mao; an hour of cooking uses about 450 liters of gas while running a lamp for an hour uses about 250 liters. And it’s “greener” to cook with biogas than charcoal.
Before installing a biodigester, families should have a reliable supply of manure.
CRDT recommends users have access to the manure from two cows and three pigs or other barnyard animals of comparable size. They will also need at least 12 square meters of land near the household’s kitchen and water source as well as materials, equipment and advice on installing the biodigester.
CRDT’s project has been so successful it has been rolled out into a National Biodigester Program, a joint venture between the Ministry of Agriculture, Forestry and Fisheries and the Netherlands Development Organization.
“You can use them for about 20 years and we have built more than 2,000 across Cambodia,” said Lam Phalleng, a coordinator for the National Biodigester Program.
It costs about $500 to construct one biodigester but over half the cost is covered by contributions in cash and kind from the community. Furthermore, loans can be provided through the microfinance organization Prassac.
The project is increasingly well-known and has been featured on Cambodian state television.
“People are very interested in our program because they immediately see the benefits: they don’t need to go to the forest to collect wood all the time like before and they can use electric cookers and lamps in their houses,” Phalleng said.