I managed to wrest these actual usage figures for wood chip from the owners at Savage Cat Farm, Gillingham, along with the RHI payments for the quarter received on 25th Feb 2013.
These are four 300′ x 80′ Morespan sheds, roughly twelve years old, heated by four ETA Hack 200 commercial biomass boilers, rated at 199kw. See : Savage Cat Farm category.
Chip usage averages out at 21 tonnes per shed per winter crop. This is bentwood that has been stored at the farm in the open for twelve months. Bought in at £28/tonne freshly felled, and chipped after the twelve months. It works out at around £45 per tonne at around 30% moisture content once you take into account the chipping cost and the loss of moisture through seasoning.
The actual RHI payments received on 25th Feb for the winter quarter (2 crops) were:
Making a grand total of £48,080.10 from a fuel cost of £7,560 — at least half the price kerosene would have been over the same period.
The figures vary from shed to shed due to exposure, air leakage, etc.