The Revenue Commissioners, who are responsible for collecting duty on motor vehicle fuel, inform me that rapeseed oil, when used as a fuel in diesel motor engines, is categorised as a substitute fuel for auto-diesel and is chargeable to duty at the rate for auto-diesel. However, as it is a biofuel, rapeseed oil is relieved from carbon charges. No differentiation is made between the different types of substitute auto-fuel upon which tax is paid. Accordingly, the duty paid on rapeseed oil cannot be ascertained specifically. In 2011 duty was collected on 73,400 litres of substitute fuel for auto-diesel amounting to €31,247. To date in 2012, duty of €42,188 has been collected on 99,000 litres of such fuel. The duty on substitute fuels, including rapeseed oil, is imposed by Council Directive 2003/96/EC (the Energy Tax Directive) and consequently a cost benefit analysis is not relevant.