厂网分离改革对热电联产企业规模经济与范围经济影响分析

A Study on Effects of Vertical Unbundling Reform on Scale Economy and Scope Economy of Cogeneration Enterprises

2003年前垂直一体化的国家电力公司,分割成11家公司包括5家发电集团和两家电网公司,2004年东北区域电力市场进行试点改革。在此背景下本文选取中国工业企业数据库东北三省55家热电企业2003-2010年财务数据,运用部分非参数前沿方法分析了热电企业的规模效率,并对热电企业是否实现横向范围经济进行了实证检验。结果表明,厂网分离改革提升了热电企业的生产效率,并没有损害五大集团热电企业实现规模经济。大多数五大集团热电企业处于规模报酬递减阶段,而大多数独立热电企业处于规模报酬递增阶段。相对于单独火力发电和单独供热企业大多数热电企业都实现了范围经济。其中相对五大集团热电企业,独立热电企业的范围经济指数更低。

In 2003,China＇s integrated electricity utility was unbundled and dismantled into five generation groups and two grid companies. The Northeast region of China was decided to be a testing ground to build a functioning wholesale power market in 2004. This article selects 55 cogeneration enterprises in this region,using their financial data from 2003 to 2010 in the industrial enterprises database of China. With a partial frontier nonparametric approach,it analyzes the scale economy of the cogeneration enterprises,and makes an empirical study on whether or not the cogeneration enterprises could actualize horizontal scope economy. The results show that vertical unbundling reform promotes the production efficiency of the cogeneration enterprises of the five generation groups without damaging their economies of scale. Most of the cogeneration enterprises in the five generation groups are on the stage of decreasing returns on economies of scale while most independent cogeneration enterprises are on the increase stage. Results also show that in comparison with the single thermal power or heat production enterprises of a higher cost efficiency,most cogeneration enterprises realize economies of scope; and the independent cogeneration enterprises has lower economies of scope index than the five generation groups enterprises.