V Measurement: vapour recovery: Vapour recovery formula approved by the Energy Institute
The formula (below) as approved by The Petroleum Institute (now known as The Energy Institute) is shown below in full, although it is currently under review and contains some now obsolete terms.
(Any amendment to this Formula will be publicised and reflected in amendments to this section of the guidance in due course).
Vapour recovery Formula
Duty reclaim = P*S*H*M*0.0000422*VT [(Ful*Dux) + (Fsul*Dsul) + (Fl*Dl]/D
|P||= The VRU performance factor|
|S||= The VRU service of availability factor|
|H||= Average TOC (total organic compound) concentration of vapour collected.|
|M||= Mean Molecular Weight of recovered liquids.|
|VT||= For VRUs with a single sample point. Volume of all products loaded through bays connected to each sample point.|
|VT||= For VRUs with multiple sample points. Volume of products loaded through bays connected to each sample point. (Where the sampled H value differs, a separate formula will be required.)|
|Ful||= Fraction of VT comprising unleaded motor spirit.|