Defra's latest statistics on land used for bioenergy were published earlier in December, and are available to download here.
It contains a number of useful statistics, including the relative increases in different feedstocks from 2012-2013 (p 25):
This shows that the industry continues to be waste-dominated, with the support of crop feedstocks for certain projects.
Defra also presents more up-to-date information from the June agricultural survey, on the intended use of maize grown in the UK. This shows a very small increase in the proportion of maize used for AD:
Defra reports that this
equates to 19% of the total maize area in 2015 and 0.7% of the total arable area.
Clearly, in the context of UK agriculture the area of land used for AD crops remains tiny.