British biodiesel users, beware of bobbies! Police in Great Britain have cracked down on users of the alternative fuel, most recently staging a bust that bagged more than a dozen motorists in the Welsh seaside town of Burry Port. Biodiesel is essentially refined vegetable oil that burns more cleanly than conventional diesel; as the folks in Burry Port know, it can be home-brewed without too much effort — and, to the dismay of the authorities, without paying the proper fuel taxes. According to Robert Buxton, a spokesperson for the Department of Customs and Excise, “If you use a substance as a fuel to propel a vehicle on the road, you have to pay duty at the rate of the substance” being substituted. Hence the alternative-fuel users were tax evaders and have been hit with heavy fines for their wrongdoings. British biodiesel advocates fear the busts will give the fuel a bad name.