Hi Andrew
I'm afraid that's a 'piece of string' question and as you can see from the post above it may well be down to postcodes.
The one thing I will say is that a commercially aware developer will be utilising the services of local planning consultants who in many cases have been council planning officers themselves. Planning for a large solar farm is costly and I'm sure they way up the percentages. There has also been a move of late to look favourably on land less suitable for traditional farming purposes.
May also be worth speaking with your local planning. I had a conversation with a planning officer from Chorley Borough Council last week and although it's only a 50kWp ground mount he was very helpful.
Cheers
Mike
Mike,
Was interested to compare with wind option really, we had to go to appeal on a 50KW Endurance recently, nine months of delay later the P Inspectorate found overwhelmingly in our favour, as did our planning officer in the first instance!. Council planning committees are full of ill informed, and often biased people who have never actually run a business in many cases.