While the ESMAP paper cited above suggests annual cost declines of 7% for gas turbine technologies, case studies from industry suggest a rate of cost decline at least double the ESMAP figure.

FORBES: Why "Green Fossils" Matter So Much To Africa's Energy Future

The 2007 World Bank ESMAP report cited earlier gave its vote to renewables principally because of what the authors saw as a quicker drop in the costs of development and maintenance compared with conventional power sources.

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