Anti-renewable energy people often claim that it takes a lot of energy to make wind turbines so they aren't as clean as they seem. Let's look at the facts.
The first thing to remember is that there's no such thing as a free lunch; building anything requires an upfront investment. Coal and natural gas power plants take a lot of energy to build too, and on top of that initial energy deficit, it also takes a lot of energy to mine coal or frack for natural gas, and then transport it in trains or pipelines, etc. With renewables, the wind and the sun are free, so after the production and installation, you're pretty much done for decades.
A new study published in the International Journal of Sustainable Manufacturing looks at the cumulative energy payback of 2-megawatt wind turbines that are used in the Pacific Northwest, precisely calculating the lifecycle energy required for manufacturing, installation, maintenance, and turbine end-of-life processing, and looking at how that stacks up against energy production over the life of the turbines (a working life of 20 years or more is not unusual).
The payback for the associated energy use is within about 5-8 months, and even in the worst case scenario, lifetime energy requirements for each turbine only takes 1 year of operation. So for the next 19 years, each turbine will, in effect, power over 500 households without consuming electricity generated using conventional energy sources, and if the turbines end up operating for over 20 years, that's just a bonus.