Nexus - 0225 - New Times Magazine-pages

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Lies Unleaded Petrol Oil companies convinced us that unleaded petrol is safer for our health and environment than leaded petrol. By their failure to disclose all the facts, we have been seriously conned! he very terms "leaded" and "unleaded" are misleading. They give the impression that "leaded" petrol is contaminated with something nasty, namely lead, while “unleaded” is somehow pristine, pure. Whilst it is true that "leaded" petrol con- tains lead, and lead is not a nice substance to have spewing out of the exhaust pipes of millions of cars, the truth is that unleaded petrol has even nastier properties. Let's start at the beginning. When internal combustion engines were first developed for the automobile, they ran on a substance known as “motor spirit". By today's standards, motor spirit was an exception- ally "clean" fuel; properly burnt in an efficient engine, the main exhaust products were water vapour, carbon dioxide and some trace carbonic elements and particles. There were two main problems with motor spirit. First and foremost, it was a highly refined product which cost the oil companies far more to produce than what they wanted to spend, or what they thought they could charge if the automobile was really to take off in a big way. Secondly, the original combustion engines ran at very low compression ratios compared to today. As the vehicle manufacturers strove to produce ever faster, more powerful engines, they gradually raised the compression ratios, as this is one of the easiest ways of gaining more power from any given-sized power plant. So, for a period, these two problems developed side by side until they eventually collid- ed with the development of the V-8 engine. On the one hand, fuels were becoming less and less refined, and therefore more contaminated with products that adversely affected engine efficiency. On the other hand, power plants were being developed which employed ever higher compression ratios and required ever more exacting performance from the fuel used. With the advent of the high-compression engine, a point was reached where cars would not run satisfactorily on the product being supplied by the oil compa- nies. An engine under load would develop a condition known as “pinging”, where the fuel mixture would explode due t@ compression before the right time, causing rough running, stalling going up hills, and so on. There was only a shortlist of answers. Vehicle manufacturers could go back to design- ing low-compression engines, the oil companies could go back to producing a highly refined product, or something would have to be found that could be added to stop the fuel pre-igniting. The first choice was unacceptable to the manufacturers. They had long since embarked on a marketing strategy that demanded ever bigger, ever more powerful power plants every year. Nobody was prepared to take the risk of producing a less-effi- cient, less powerful engine than the one offered the year before. The second choice was unacceptable to the oil companies. They had perfected the technique of producing a fuel with a minimum of refining, that could still be burned in engines, at such a low price and in such quantities that they were well on their way to becoming the richest, most powerful companies on Earth. They had no intention of greatly increasing the cost of their product, thereby turning many people off the "advantages" and "economy" of owning their very own car. The third choice was the only acceptable one. All that was needed was to find some product, something that could be obtained cheaply, that could be added to petrol to reduce its tendency to "ping" under compression. Common lead was found to have all the right properties, and so "leaded" petrol was born. By the late ‘sixties, supplies of high-grade, low-sulphur, low-nitrate oil were becoming scarce enough to command premium prices. This type of oil was favoured by the petrole- um producers, since removing these contaminants to an acceptable level is difficult and By their failure to disclose all the facts, we have been seriously conned! Compiled by Catherine Simons from articles by Peter Sawyer Graham Allum Simon Grose from articles by Peter Sawyer Graham Allum Simon Grose NEXUS ¢ 45 APRIL - MAY 1995