There is no such thing as a perpetual motion machine, multi level marketing is a scam that makes a few people rich, if everyone in the world quit their jobs to make money buying houses for no money down we would all die broke of starvation in a few months, there is no practical way to make a cheap flying car for the masses, flying jetpacks do not work (cannot carry enough fuel), and it is simply not going to be possible to send a human being to Mars. All these statements are true or will likely be proven true in the future. Most come up against the cold hard laws of physics and die right there. The problem is with wrong ideas that are given longer lifespans than reality by itself would allow.
Case in point, these windmills in Minnesota. The real story is not that they don't function in cold weather but that they cost $400k a pop to make 160kw of power (when the wind blows more than 12 miles per hours and the temperature is not below 1 degree Fahrenheit). The $400k is just the startup, these things have to be maintained and to acheive the 25% renewable energy that the state is going to mandate, you will need thousands of these things. What is the cost on maintaining thousands of small generators. Granted, they will probably buy bigger turbines if they get serious about meeting the 25% requirement but still it will have to be many thousands. Looking at this site, the average coal fired plant probably generates about 500 MW of electricity 24 hours a day, 7 days a week, regardless of temperature or wind speed. You need 71 of these big boys running at capacity all the time to replace 1 medium sized coal fired plant. Did I mention this windmill is only a prototype? Nothing this big is currently in production. Estimates seem to range for initial cost from $1000/kwh to $2000/kwh so for 7 MW that would be $1000*7*1000 or $7 million on the low side per unit. If government was not involved and companies were left to themselves to find the most profitable way to generate electricity, this would not be it. I am not saying we should burn coal until the skies are black with soot, where I live used to be a major steel producing town and the area where the steel mills were was called the valley of fire. No one wants to go back to the days when the valley was covered in smoke and soot rained down on peoples houses. But to suggest that Minnesota is going to meet its 25% renewable energy generation requirements with windmills is like ignoring the laws of gravity which is exactly what is happening on a widespread basis.
All across the country bad ideas are not dying and not being disproved. Instead they are being put on life support by government. A certain amount of bad ideas can be tolerated but there must be a tipping point where society's delusions reach critical mass and explode. Ideas that bypass the harsh Darwinian testing of reality can be dangerous as they suck up resources and lead people down a path that separates them from reality. In nature this doesn't happen, if a mouse is born an albino the success of this change is proven or disproven quickly. Someday the government is going to build the 71 windmills and scrap a conventiional power plant (coal, nuclear, hydro, whatever). Some winter it is going to get cold and either the wind won't blow or the windmills will freeze or there won't be enough mainenance people to keep enough of them running. Depending on how far down the path the government has led us away from reality, there may not be enough capacity from the remaining conventional power plants to take up the slack and people will freeze and or starve. This is not the way to find out our ideas were wrong.