ENGINEERING WITH GORDON

What are Biofuels?

Engines running on alternative or biofuels have been operating for a number of years ashore but have made little impact in the commercial marine and yachting worlds.

The world renowned leader in diesel biofuel technology, MAN Diesel, became involved with liquid renewable fuels (plant oils) back in 2001, when the company supplied one of its inline, four stroke engines to an electrical power plant in Germany. Since then MAN Diesel four strokes have logged many operating hours on liquid biofuels, including waste oils and fats.

The only notable use of biofuels in the marine world is “Earthrace”. Earthrace is a wave piercing trimaran powerboat built to break the ‘Round the World Speed Record by a powerboat. By running on exclusively 100% biodiesel fuel, and with a net zero carbon footprint, it aims to promote awareness of the environment and the sustainable use of resources. Earthrace will commence her global quest from Valencia, Spain, in March 2008.

What is a biofuel?

Biofuel can be broadly defined as solid, liquid, or gas fuel consisting of, or derived from biomass. One type of biomass is wood, which is frequently used in industry, either by itself to create energy or with other combustible matter, such as coal, to burn and create heat.

Biofuel is considered a means of reducing greenhouse gas emissions and increasing energy security by providing an alternative to fossil fuels. However, in October 2007, a report was published stating that the advantages of reduced carbon dioxide emissions are more offset by increased nitrous oxide emissions. Nitrous oxide is both a potent greenhouse gas and a destroyer of atmospheric ozone.

Humans have used biomass fuels, that is, solid biofuels, for heating and cooking since the discovery of fire. Following the discovery of electricity, it became possible to use biofuels to generate electrical power as well. However, the discovery and use of fossil fuels, namely, coal, oil and gas, have dramatically reduced the amount of biomass fuel used in the developed world for transport, heat and power.

The abundant supply of cheap Middle Eastern oil, after World War II, lessened interest in biofuels. But the oil shocks of 1973 and 1979 increased interest from governments and academics. The counter shock of 1996 again reduced oil prices and interest.

In the United States, all cars manufactured since 1988 are required to be compatible with fuels containing at least 20% ethanol, E20 fuel, and with minor modifications, these cars can use 85% ethanol blended with petroleum, E85 fuel.

Since around 2000 renewed interest in biofuels has been seen. The drivers for biofuel use and development include rising oil prices, concerns over the potential oil peak, greenhouse gas emissions (global warming), rural development interests, and instability in the Middle East.

Second generation biofuel production processes are in development. These allow biofuel to be derived from any source of biomass, not just from food crops such as corn and soy beans.

Why are biofuels not in great use in the yachting world?

At the present time, untreated plant oils can cause severe problems to high speed engines designed for operation on high grade distillate fuels. However, you can be assured that these problems will be sorted out within the next couple of years and it will then be commonplace for that used cooking oil from the galley to be poured into the main engine fuel tank.