Really magical diesel

I refer to the letter by Prof. E.A. Mallia and Prof. E. Sinagra, entitled 'Magical diesel' (June 13) and point out that, irrespective of the fact that mineral diesel ex-Enemalta is now said to have a sulphur level of 0.5 per cent, this in fact is still in excess of that contained by biodiesel. Statistical data about the tailpipe emission changes with biodiesel compared with those of fossil diesel are:

¤ Carbon monoxide biodiesel produces 43.2 per cent less;

¤ Hydrocarbons biodiesel produces 56.3 per cent less;

¤ Particulates biodiesel produces 55.4 per cent less;

¤ Nitrogen oxides biodiesel produces 1.2 per cent more;

¤ Air toxics biodiesel produces up to 90 per cent less;

¤ Mutagenicity biodiesel produces up to 90 per cent less; and

¤ Carbon dioxide (life cycle emissions) biodiesel produces 78.3 per cent less.

Biodiesel is also oxygenated, which means that it burns more cleanly and completely than fossil diesel.

Coming back to sulphur content, I would like to stress that the lower the percentage in fossil diesel the more corrosive this becomes on fuel injector pump and seals, and this is where biodiesel comes into play as, with half per cent addition, it gives back to fossil diesel the lubricity it has lost, plus an increase of approximately 18-20 per cent.

As for fuel hoses, biodiesel uses the same grades as that of low sulphur fossil diesel. In fact, nearly all reputable car manufacturers have switched to these grades since 1994.

This leads me to the reference to cancer.

Evidence indicates that diesel particulate matter is a potential carcinogen, so much so that in 1988 the National Institute for Occupational Safety and Health in the US recommended that whole diesel exhaust be regarded as "a potential occupational health carcinogen" as defined by the cancer policy of the occupational safety and health administration.

Now research has proved that particulate matter - and specifically the carbon or insoluable fraction - is significantly reduced when biodiesel is used. Furthermore, besides all this, the pollutants and carbon (the compounds that are prevalent in biodiesel and diesel) exhaust are different, with research showing that the exhaust from biodiesel is much less harmful than that of fossil diesel where carcinogen is concerned.

I can keep going on and on, highlighting the inaccurate and misleading assertions in the learned professors' letter.

However, let me speak about the undisputed benefits biodiesel has for the man in the street.

A 20 per cent blend, or using biodiesel as an additive, keeps Nox increases small (1.4 per cent) and within the legal emission limits for engines.

A 20 per cent still gives good emission benefits by reducing soot, particulates, hydrocarbons, carbon monoxides, and carbon dioxide by more than 10 per cent.

A 20 per cent blend does not create problems with filter plugging and deposits formation that can result from the interaction between biodiesel and the accumulated sediments and sludge that form in normal diesel storage tanks.

Advantages of biodiesel:

Biodiesel is CO2-neutral (reduction of greenhouse gas effects); it is free of sulphur (reduction of acid rain and harm to trees, forests and building); it has a rapid biological decomposition; is not classified as a hazardous material; lowers local active emissions (e.g. CO, Sox, CH, Nox, soot); it shows very good lubricant characteristics; and has husbanding abilities in regard to motor engines.

Extensive studies of different scientific institutes proved that biodiesel shows a positive energy balance. The production of the raw materials, the processing, as well as the usage of biodiesel and the other products of the process were considered within the studies. On the contrary, some known studies of the mineral oil industry declare negative product characteristics.

Few compatibility problems arise. Operating performance is identical with fossil diesel in terms of horse power, torque and haulage rates. Biodiesel can be used in existing diesel engines and fuel injection equipment without negative impact to performance and without engine modifications.

Above all, the special feature of biodiesel is that its lubricity is greater than that of fossil diesel. This is very important for the wear and tear of the engine.

Stanadyne Diesel System and Bosch Diesel Fuel Injection Service in the US issued service letters to distributors and dealers concerning the lack of lubricity caused by low sulphur diesel. Pump manufacturers recommended use of lubricity additives to alleviate the serious damage occurring to their injection pumps. Testing at highly accredited institutes, such as the Southwest Research Institute, has demonstrated that biodiesel shows significant lubricity improvement compared to diesel.

In conclusion, I would like to quote from a document presented to the UK cabinet by BABFO in September, 2001, where they state: "Biodiesel by contrast is sustainable, renewable, creates energy (through the utilisation of the sun's energy), and recycles carbon, thus aiding the concept of a low carbon (dioxide) economy. Each unit of energy put into producing the fuel (on a cradle to grave basis) is doubled or even quadrupled if the by-products are efficiently used for energy promotion."