Energy Efficiency and Directed Technical Change: Implications for Climate Change Mitigation
构建了一个经济增长与能源效率的定向技术变革模型，研究气候变化减缓政策对能源使用的影响，发现标准生产函数高估了能源税对累计能源使用的削减效果，并分析了政府如何结合能源税与研发政策来最大化福利。
Abstract I develop a directed technical change model of economic growth and energy efficiency in order to study the impact of climate change mitigation policies on energy use. I show that the standard Cobb–Douglas production function used in the environmental macroeconomics literature overstates the reduction in cumulative energy use that can be achieved with a given path of energy taxes. I also show that, in the model, the government combines energy taxes with research and development (R&D) policy that favors output-increasing technology—rather than energy efficiency technology—to maximize welfare subject to a constraint on cumulative energy use. In addition, I study energy use dynamics following sudden improvements in energy efficiency. Exogenous shocks that increase energy efficiency also decrease the incentive for subsequent energy efficiency R&D and increase long-run energy use relative to a world without the original shock. Subsidies for energy efficiency R&D, however, permanently alter R&D incentives and decrease long-run energy use.