Very different subsidies. The companies that built solar power generation in 2004 got a guarantee of a certain price for x years, and a guarantee that the peop

Very different subsidies. The companies that built solar power generation in 2004 got a guarantee of a certain price for x years, and a guarantee that the people who built in 2005 would get a lower price. IIRC the price decrease was set in advance. In effect a market introduction price, for a limited time. The sums are low/high until the market introduction ends, and the producers knew that as long as they could innovate 10%/year they'd make a profit. (Except that the actual number wasn't 10%.) The companies that ran coal mines got a subsidy with no defined end-by date, and one cannot by any stretch of the imagination call it "market introduction aid" or "conditional on 10%/year innovation".