Finnish diesel gensets manufacturer Wärtsilä has successfully tested of a range of new biofuels which, it says, has improved the likelihood that the use of renewable biofuels in diesel engines will become more widespread.

The engine manufacturer says that it has successfully performed a number of tests using a variety of vegetable and animal based oils in its engines. The tests not only demonstrated the ability of its engines to adapt to such fuels, but have also indicated that such fuels have a promising future in the power plant market.

“Liquid biofuels represent an emerging market,” said Vesa Riihimäki, Vice President, Power Plant Technology at Wärtsilä. “We see that fuel supply infrastructures for crude vegetable oils are being developed at an increasing pace, suggesting that the availability of such fuels will be vastly extended during the next 5 to 10 years.”

The tests were conducted between February and April 2009 and involved running a Wärtsilä Vasa 4R32 engine on jatropha oil, fish oil and chicken oil. Such oils are thought to have potential in the energy market as they are renewable and their production does not compete with other agricultural or food production processes.

The main aim of the tests was to gain some experience with alternative fuels, and to verify that the engines would behave as expected in terms of performance and exhaust gas emissions, says Wärtsilä. The company concluded from the tests that most animal fats are similar to conventional diesel fuels in terms of energy content, and ignition and combustion properties.

The main differences are the melting point, the level of impurities, and the degree of acidity.

Niklas Haga, chief development engineer, Wärtsilä Power Plants commented: “We have successfully tested and operated our engines using various vegetable-based oils in the past, now we are in the process of looking at animal-based oils. As a result of these tests, we are confident that we can operate our current engines on these renewables.”

Wärtsilä has already earned some success in the jatropha market, securing a contract in April 2008 for an engine-based power plant in Belgium that will run on jatropha oil. The company performed its first engine test with the fuel oil in January 2009 and plans to conduct additional tests later this year.

Jatropha oil is thought to have great promise as a future energy source as it is extracted from the seeds of a non-edible, high-energy fruit from a plant that is grown on semi-arid or marginal land in Asia, Africa and Latin America. Fish and animal oils have similar promise as they are produced as by-products of existing commercial processes.

Wärtsilä carried out tests with fish oil in February 2009 and with chicken oil in April 2009. The tests with fish oil showed that the engine performed in much the same way as when running on vegetable-based oils, and the company says that no further testing is needed for evaluation purposes at this stage.

Fish oil contains 10-30 per cent fat, depending on the species. The global production of fish oil in 2007 was 1.1 million tonnes, exceeding the amount needed for food supplements.

The demand for biofuels has risen steeply in recent years, driven by renewable energy policy in Europe and North America. However, the potential environmental impact of their production has led to concerns over their true sustainability.

To meet the demand for biofuels, land used normally for food crop production is now being used for biofuel crop production and is thought to have led to increases in food prices, especially in less developed countries.