His assertion that wind energy is less expensive than the fossil fuel alternative is not accurate if one accounts for the costs on the basis of conventional accounting methods. It was at that time more expensive which is why it’s use was limited. However, the existing methods of accounting did not charge the fossil fuels for the environmental degregation that they cause and the cost to society to overcome these or live with them. More important there is no charge to the cost of fossil fuels for the deleterious health effects that their extraction and use cause. Global warming / climate change is not considered at all in the economic analysis.