The Natural Environment Research Council has released its success rates for 2008/09 by institution and department:
The average success rate across the sector for NERC grants is 24%, but there are significant differences between institutions as you’d expect. Lincoln, for example, only submitted 1 proposal which was unsuccessful. Even some of the larger research-intensive organisations, however, scored lower than average: Newcastle achieved 19%, Nottingham 15%, Kings College London 10% and St. Andrews 14%.
I do not know how they decide who gets what and when, you would have to be cousins with someone at number 10