Lark Energy took the case to appeal after it was refused by Waveney District Council on landscape grounds in February. The size of the proposal had been reduced from 30MW following objections from local residents.
In his report, the inspector said that harm to the character and appearance of the landscape was "limited".
However, Pickles later ruled that the damage that would have been caused to the local landscape outweighed the benefits from renewable energy generation.
His decision letter stated: "The secretary of state agrees with the inspector that the harm to the character and appearance of the area would not amount to significant adverse effects but, nevertheless, considers the effect on the character of the site, although limited, would be adverse."
The council had already approved a solar farm to the north of the appeal site, Pickles noted. This project would have less landscape impact than the appeal proposal, he said. The project at appeal would also harm an agricultural landscape character area, he judged.
Lark Energy managing director Jonathan Selwyn said that Pickles’ decision had caused great concern in the renewables industry. He said: "It is very rare for the secretary of state to overturn an inspector’s recommendation and this was not a borderline case.
"If the secretary of state decides to ignore an inspector it clearly has serious implications."
It was only the second solar farm project to be decided by the secretary of state, the other being a 3MW project in South Northamptonshire. But in October Pickles pledged to intervene in more renewable energy planning decisions.