中国能源效率波动:理论解释、数值模拟及政策含义

The Fluctuations of China's Energy Efficiency:Theoretical Explains,Numerical Simulations and Policy Experiments

本文从波动角度分析了中国能源效率的变化,特别强调波动成分对能源效率的短期影响,并在动态随机一般均衡框架下构建能源效率的机制决定模型,以探讨不同冲击对中国能源效率波动的作用差异。本文的理论分析和数值模拟表明:(1)内生的资本利用率变化可以成为决定中国能源效率波动的关键机制,能够分别解释改革以来产出能效波动的81%和资本能效波动的97%;(2)全要素生产率、能源价格和政府消费的冲击对能源效率的影响差异很大,暂时性生产率冲击在短期内对产出有较大的刺激作用,但产出能效只有小幅提升,政府购买增加会导致经济的剧烈过度调整;提高能源价格能大幅提高能源利用效率且对产出的影响相对较小。这要求政府更为准确细致地把握经济形势、及时相机做出恰当的反应,更多地采用政策组合方式,以最小福利代价取得最大经济效果。

Based on the HP filtering analysis, the stylized facts and important influence of China＇ s energy efficiency fluctuations are detected in the article, and then a dynamic stochastic general equilibrium model is developed to describe the mechanism of energy efficiency change in the short run. This simple RBC model depending on the endogenous capital utilization as the key point, together with three exogenous shocks from total factor productivity, energy price and government expenditure, accounts for 81 and 97 percent of volatility of out-energy and capital-energy efficiency during 1978--2006 respectively. And the numerical experiments also show that the composite policy tools can regular the energy efficiency with the less welfare cost than the single one. This means that the diverse efforts to improve the energy efficiency, not only from the trend but also from the cyclical aspect, should be considered more seriously in the future.