Even seemingly purposeful projects can seriously backfire: only a few years ago, Europe’s well-intentioned efforts to stimulate renewables resulted in a solar energy bubble of macroeconomic proportions. Whereas cutting greenhouse-gas emissions is necessary, the current generation of relatively inefficient renewables should not be deployed at the expense of the development of more cost-effective technology.
即使是带有明确目的的计划也有可能适得其反：几年前，欧洲带着良好的意愿尝试刺激可再生能源投资，结果导致了宏观经济出现太阳能泡沫。尽管减少温室气体排放很有必要，但不能让当前效率相对较低的可再生能源阻挠成本效益更好的技术的发展。