Being green was not enough on its own to persuade policymakers, despite increasing urgency on irreversible climate change.
To a large extent, wind power has succeeded in this aim. Its costs, of course, vary widely according to location and the age of the hardware deployed.
But recently built projects in most parts of the world are now generating electricity at a levelised cost of energy that compares well with thermal sources, despite low prices for oil and gas, while offshore costs are falling faster than anyone expected.
Reaching this goal has not been easy. The industry has made huge progress in the design of wind turbines, which are now of an order of magnitude greater in power, efficiency and reliability than those of even five or ten years ago.
The policymakers who demanded clean energy-generating sources with a minimal economic impact on bill-payers have got what they wanted. So why are so many of them still so sluggish to respond?
The COP 24 UN climate change summit in Poland’s Katowice ended on 15 December with a rough deal agreed on how to implement the 2015 Paris Agreement, but leaving many of the details to the next summit.
Failure to deliver
The overall tone of the summit was not encouraging, though.
In his opening address, Poland’s president, Andrzej Duda, boasted that his country was sitting on 200 years worth of coal supplies and that "it will be hard not to use them".
Of the 50 most polluted cities in the EU, 36 are in Poland, causing nearly 50,000 premature deaths a year.
How do you get elected with that much contempt for the health of your people?
Only the most rabid deniers now refuse to accept the science of climate change.
And only the most criminally unaware fail to recognise that the means of generating clean energy at competitive costs are widely available.
Jennifer Morgan of Greenpeace summed up the reactions for many as the COP 24 talks concluded: "A year of climate disasters and a dire warning from the world’s top scientists should have led to so much more.
"Instead, governments let people down again as they ignored the science and the plight of the vulnerable. People expected action, and governments did not deliver. This is morally unacceptable."