Interesting pargraph below, i cant seem to locate the study in...

Interesting pargraph below, i cant seem to locate the study in question, though still looking.

http://freeinternetpress.com/story.php?sid=23844

Will 'Cleantech' Be Next Economic Miracle?

"At any rate, photovoltaics is by far the most expensive method. It costs more than €600 to reduce CO2 emissions by one ton. For wind energy, that cost is reduced to about €100 per ton. It would be more worthwhile to improve the efficiency of brown coal power plants, for example. According to a study by the McKinsey consulting firm, that would cost less than €20 per ton. In other words, the money that is spent to save one ton of CO2 with solar power could be used to save up to 30 tons in coal-fired power plants."