Cheap alternatives

摘要

Cheerleaders for renewable energy are fond of pointing out that patches of desert receive enough energy each year from sunlight to power the entire world. But few deign to explain how the construction of the millions of solar cells required to convert that energy into electricity would be financed. Utility bosses and policymakers tend to dismiss wind and solar power as noble but expensive distractions, sustainable only through lavish subsidies. But new studies suggest that renewables might not be as dear as sceptics suspect.