We wouldn't be at this point (this early) without large public investments, regulation, and advocacy. Simply saying "oh the market's got it, we cool" is misguided thinking.

Public awareness and advocacy matter more, I think. We're not regulating coal out of existence, or they'd be closing from regulation, not cost. And the public investment isn't what's driving the radical drop in wind/solar manufacturing and installation costs. That's regular economy of scale stuff.

Not at all.

It's been government regulations promoting renewables around the world which have helped drive demand. This in turn has led to Chinese factories ramping up and the overall cost dropping.

Same thing with electric cars. The current explosion in new models is being driven by EU regulations not consumer demand.

They are closing because alternatives are cheaper, which has multiple reasons, some of which are policy (subsidies/penalties, publicly funded research in alternatives, stricter mining regulation driving resource prices up, stricter emissions regulations requiring expensive plant upgrades or more expensive new construction etc.)

I did a little googling, and new coal plants in the US are no more expensive - price/mwh held steady at $95-100 from 2010-1015 (after which no one built any more). Meanwhile, in 2010-1019, natural gas plants dropped in cost/mwh by about 50%, from around $80 to $40. And onshore wind dropped 71%, from $149 to around $43. Solar dropped even more (88%), from $396 to $49!

As an aside, new nuclear dropped from $119 to $90, and there are no new plants planned - small wonder, considering the massive cost and long time frame to build nuclear when wind and solar cost half as much and prices are still dropping like rocks.

But you are forgetting the huge amount of subsidized R&D (via universities) and subsidized investment costs that has already been spent. Without that, it is very hard to believe that the wind power industry would have bootstrapped itself.

The same can of course be said for the nuclear industry. Without massive R&D spending and cheap capital costs, nuclear energy would never have been viable. Today, wind and solar is beating both nuclear and coal, which is great. But perhaps The Market shouldn't get all the credit.

Isn't it pollution regulations that make coal uneconomical? Coal is still a cheap option in China, for example. Have we simply used up our supply of cheap coal?

No, it's that alternatives (mostly natural gas) have become much less expensive than they were, to the point where they're cheaper than coal to operate. Fracking completely changed the game, giving us access to a great deal of previously unrecoverable natural gas. (Oh, and speaking of government investment and subsidy...)

The really interesting thing is that solar/wind are becoming cheaper than coal, and will soon be cheaper than natural gas.

One of the easiest ways for companies to claim huge carbon emission reductions is for them to buy old coal plants and shut them down.