The world’s biggest wind turbine manufacturers have committed to eliminating their net emissions of greenhouse gases, but reducing the carbon footprint of their production process may mean customers have to bear some of the cost. Global players such as Denmark’s Vestas Wind Systems A/S and Siemens Gamesa Renewable Energy SA , its German-Spanish rival, aim to hit an array of sustainability targets in the next decade. These range from building zero-waste turbines to reducing the emissions of their supply chain, posing the challenge of rising costs in a market where margins are already lean. Unlike coal or natural gas power plants, wind energy does not emit the greenhouse gases that are responsible for global warming. But making the turbines needed to generate that power does. Wind turbine blades are made from a combination of fiberglass and resins that can’t yet be recycled in a cost-effective way. Steel, another key […]