Bio-Fuel
Most transport fuels, such as petrol, diesel or LPG are derived from oil or its by-products. These are all fossil fuels that when burnt give of carbon dioxide emissions that contribute towards global climate change. Biofuels are transport fuels that are processed from crops, and can be used as substitutes for some or all of the fossil fuels in petrol or diesel. Because as much carbon can be captured in the growing stage as is released when they are burnt in vehicles, they can – at best – be carbon neutral. In practice, some fossil fuels are used in the production of almost all biofuels, and so they can only partly eliminate harmful CO2 emissions.
Jump to :
- What types of Biofuels are available?
- Why should we use Biofuels?
- Where can I buy Biofuels?
- How can I produce my own Biofuel?
What types of Biofuels are available?
There are two main types: biodiesel (which can replace mineral diesel) and bioethanol (which can replace petrol). In practice four main products are produced for sale in Europe:
| Diesel | |
| B5 (typical biodiesel) | A blend of 5% biodiesel and 95% mineral oil |
| B30 | A blend of 30% biodiesel and 70% mineral oil; hard to find in the UK but approved for use in all new Peugeot/Citroen diesel engines. |
| Pure Biodiesel | 100% biodiesel, typically made from waste vegetable oils |
| Petrol | |
| Tesco 99 Octane | Despite its name, this typically includes 5% bioethanol |
| E10 | A blend of 10% bioethanol and 90% normal petrol |
| E85 | A blend of 85% bioethanol and 15% normal petrol |
The situation is complicated because the percentages vary between countries, and there are many different biofuel crops (feedstocks) which vary in their impact on the environment. Also, although most diesel vehicles can run on B5, relatively few cars are able to run on pure biodiesel, and not all European petrol cars can run on E10 or E85. Running a car on a biofuel blend (other than B5 for diesel) may invalidate the manufacturer's warranty, or may requiring some adjustment to the tuning. If in doubt, contact your manufacturer or an authorised service dealer.
The "greenest" biofuel is pure biodiesel made from recycled waste oil, such as used chip fat. This needs relatively little processing after filtration, but – despite our love of fish & chips – is only available in limited quantities. Pure biodiesel is also liable to become sticky in cold winter weather, leading to reduced performance. It is not normally available from filling stations, but may be available through biodiesel clubs, or direct from a supplier.
Most oilseed crops grown for biodiesel need a certain degree of refining before they can be used: eg. oilseed rape is converted to a product called rape-methyl-ester (RME). The main feedstocks for European RME are the yellow fields of rapeseed that can be commonly seen in the countryside in early summer. However, the UK is also importing some biodiesel feedstocks from other parts of the world, including soy beans from USA or Brazil and Palm Oil from SE Asia. Other sources of biodiesel include jatropha, a tropical plant that grows on marginal land, but most of this is likely to be used in its country of origin.
Bioethanol can be produced from almost any starchy crop, including sugar cane, sugar beet, potatoes grain (wheat) and corn (maize). In the UK we are mainly concentrating on producing it from wheat and sugar beet, although we are also importing some from Brazilian sugar cane. (In contrast most US ethanol comes from corn.) In future, scientists hope to be able to produce ethanol from cellulose, such as wood, grasses or wheat stalks, as these crops are often either waste products or do not compete directly with other food crops for land.
Bioethanol is almost always blended with petrol to improve its performance, and because pure ethanol (alcohol) is extremely prone to mixing with water. (It is, of course, the common "alcohol" in all alcoholic drinks, such as whisky, wine or beer. Indeed until the 1970s, a bioethanol blend made from a by-product of the Scotch whisky industry was widely on sale in Britain.)
Why should we use Biofuels?
At their best, biofuels are a renewable resource that make a significant contribution towards reducing net CO2 emissions, and hence to combating the threat of climate change. If grown sustainably, they add to local employment and can improve security of energy supply, as they tend to grow best in countries that are not major mineral oil exporters.
However biofuels are not without their critics, who would point out:
- At the 5% or 10% level, more cost-effective carbon savings can often be made by investment in cleaner vehicle technology, and that when B5 is marketed as "biodiesel" it gives motorists a false impression of being green;
- Many biofuels compete for prime agricultural land with food crops. This can raise food prices and is claimed to have been responsible for food riots in Mexico when US demand for corn for bioethanol caused tortilla prices to rocket! And in any case, with current levels of global petrol and diesel consumption, there is just not enough good quality land available to meet the demand if they were wholly supplied by biofuels;
- Some biofuels have a poor CO2 balance – so that although they save some CO2, it's nothing like as much as appears at first sight. Bioethanol from wheat only saves around 25% of the CO2 compared to normal petrol, and biodiesel from oilseed rape around half the emissions;
- Expanding plantations for Palm Oil have led to deforestation in SE Asia, degrading the environment and threatening wildlife such as orang-utans.
Where can I buy Biofuels?
B5 (regular biodiesel) is widely available through filling stations as it meets the existing BS for diesel. It's most likely to be found on supermarket forecourts, such as Tesco, or through independent suppliers such as Rix (which supplies three locations in Shropshire).
B30 is still hard to find.
Pure Biodiesel can be bought straight from the supplier. There are a small number of suppliers in Shropshire and Cheshire. Please note that some suppliers give preference to regular local customers, to discourage drivers travelling long distances to obtain their supply.
E5 can again be sold within the existing BS for unleaded petrol, so may not be marked as such. It's often available at Tesco (99 Octane) or Morrisons stores.
E10 and E85 are only on sale at a handful of UK filling stations at present, with none known in Shropshire or Cheshire.
How can I produce my own Biofuel?
If you have a large source of waste cooking oil, then it may be worthwhile looking at buying a small plant to process the oil yourself. If the oil it to be used for road use (as opposed to substituting for red diesel) it will be necessary to set in place arrangements to pay duty on all the fuel produced. Alternatively you could contact one of the existing local suppliers to see if they would like to buy your supply, or to barter it for refined biodiesel. (Bear in mind that they will have to pay the tax, so will return considerably less biodiesel than used oil provided.)
If you are a farmer looking to grow crops for biofuels, then oilseed rape appears to be the crop with the greatest current potential in Shropshire or Cheshire. A large agricultural co-op has an arrangement with the UK's leading biodiesel (RME) refiner, to acquire feedstocks, and it seems likely that demand will exceed UK supply for some years, especially now the EU has set a target of 5.75% of road fuels to come from biofuels by 2010. You are strongly advised to find a potential customer first, as the spot market price for biofuel feedstocks can fluctuate quite widely, owing to relatively low levels of supply and demand.
Farmers may also consider using anaerobic digestion to produce biogas that can either be used for heating farm buildings, such as greenhouses, or potentially stored for use in vehicles. Specialist advice should be sought if you are interested in this option.
