The energy company said the risk was "very low, moving into hypothetical" but conceded it was possible after a retired teacher said he had been ordered to leave the area around a wind farm in Argyll while walking with his family shortly after the turn of the year.
 
ScottishPower said it did not have a record of the alleged incident, and no complaint had been made. The company played down the significance of the claim, with a spokesman joking that the danger from wind farms could not be compared to that posed by uranium.
 
However, Alan Clayton, a retired history teacher, from Strachur, in Argyll, said ScottishPower staff had left him and his family in no doubt that there was a real issue when they were walking in the hills near his home.
 
He said: "It was about 2 or 3 January and we were walking near the Cruach Mhor wind farm. We were right among them. It was pretty cold but not freezing. There was snow about, but it wasn't below freezing, I think.
 
"There were two [ScottishPower] people in a 4x4 van. They came shooting across as fast as they could do and said 'Get out of here quickly, because there are big chunks of ice coming off these blades' and that it had been doing it all afternoon.
 
"We just got the hell out of there. He said that we shouldn't be there. I don't know why - the gate wasn't locked or anything. There are about 40 turbines up there. It's in an ideal place for wind farming because it's not obtrusive. It's in a bowl up in the hills. But this is a walking area, people walk through quite a lot."
 
Mr Clayton said he had stood as an SNP candidate in the local elections, but, despite this, he was opposed to wind farms and in favour of nuclear power. He said: "I fear they'll damage wildlife and tourism. I'm not happy about them at all. I'm keen on nuclear power. I feel it is the most potentially productive energy source of them all."
 
He said if there was a danger posed by flying ice, the authorities should "restrict the number of inshore wind farms".
 
A ScottishPower spokesman played down the dangers of flying ice but stopped just short of denying it could happen. "In general, there is no ice formation to any degree unless you have got exceptional weather conditions," he said. "It can happen. Ice can form on anything, but the idea that ice can pose any danger ... our risk assessment is very low. Anything is possible, isn't it?
 
"You are talking about a very low risk; we're moving into hypothetical questions. The chances of it happening are very, very low risk. It's not uranium.
 
"We have got people controlling things. The conditions are pretty rare."
 
Richard Dixon, the director of environmental campaign group WWF Scotland, agreed that in certain weather conditions ice might form on the blades of the windmills and then come off "just as ice could build up on someone's roof and fall off".
 
However, he added: "It's not something I've ever heard of - it must be pretty rare. And if the guy was intercepted by people from ScottishPower, I would say ScottishPower was on the case.
 
"I'd still rather go for a walk near a wind farm than sit on a beach near a nuclear power station."