Future is filling up your car with sea lettuce and slurry
Published 27/11/2013 | 01:00
Irish motorists could be relying on farm slurry, silage and sea lettuce to produce fuel for their cars in the near future, according to a leading transportation engineer.
Dr Jerry Murphy, a lecturer in transportation engineering in UCC, has highlighted the potential for biomethane produced from the anaerobic digestion of slurry and grass to meet a new directive from the European Commission.
The latest directive from Brussels dictates to member states that it wants biofuels to be produced from residue such as food waste, slurry and other by-products. Under the new rules, by 2020, Irish citizens should never be more than 150km from a service station where they can fill a car with compressed natural gas.
The rule will mean the development of around 25 natural gas stations dotted throughout the country.
Speaking to the Farming Independent, Dr Murphy said farmers could play a key role in producing the natural gas by providing grass, slurry and other materials to feed anaerobic digesters.
"If we had 1.1pc of Ireland's area of grass or 44,000ha of grass available for co-digestion with slurry, we could produce enough biogas to meet Ireland's 2020 target for biofuel use in transport," he said.
"There are lots of areas of grassland and farms in Ireland where the grass is not used to its maximum and there is a huge potential to use grass to produce biofuels," he added.
The engineering expert added that food waste and even seaweed could be used to generate biogas which could be supplied to the natural gas grid and used to fuel transport fleets. The idea is being driven by the Europe Commission's Alternative Fuels Directive.
Dr Murphy and his team in UCC are working on a project that could see farmers in west Cork harvest seaweed from local beaches to be digested with farm slurry to produce biogas.
"There are 80ha of sea lettuce -- a horrible algal bloom that smells of rotten eggs -- exposed on Timoleague beach when the tide goes out. If digested with slurry at a ratio of three parts slurry to one part algae, as we have done in UCC, we can produce methane," he explained.
"If we could scale up methane production to a situation where farmers could be paid for taking the sea lettuce off the beach and then get paid for the methane, we could create a very sustainable and environmentally sound fuel supply," maintained the lecturer.
Some 10,000t of sea lettuce are washed up on west Cork beaches annually, which would be enough to produce fuel for 264 cars for a year.