91�ȱ�

The production of carbon neutral fuel - biodiesel - from cooking oil, animal fat and plants. At a biodiesel refining plant in Motherwell, 35,000 tonnes of old cooking oil and animal fat is filtered each year and chemically converted into diesel fuel. The fuel is mostly mixed with normal diesel to power lorries and some cars. Biodiesel is produced from plant material so is, in theory, carbon neutral. The reason for this is that the plants that biodiesel is produced from consume the same amount of carbon dioxide as is produced when the biodiesel is burned

Students could role-play working in a car dealership and selling biodiesel or cooking oil-powered cars to each other. Students could have fun trying to sell a biodiesel or cooking-oil fuelled car to someone who is environmentally conscious, or trying to dissuade someone from buying a biodiesel or cooking-oil powered car if a flashier, more expensive car is available.

Students who take on the role of car dealers will need to research the advantages and disadvantages of biodiesel and cooking oil-powered cars in advance in order to impress their customers. There could even be multiple car dealerships running at once so that whoever has the best sales pitch (knows the most about biodiesel) wins the customer. Students could swap roles to ensure everyone takes a turn as a car dealer.

Students could also be challenged to investigate how the use of biodiesel would help with the fight against global warming and how more individual drivers and companies could be encouraged to switch to using biodiesel. Also challenge students to consider the disadvantages of biodiesel production.