居民家庭生活用能是能源消费的一个重要组成部分。随着居民生活水平的不断提高和城镇化的扩大,居民生活用能需求将不断攀升。推广高效节能家用电器是促进家庭节能的重要途径之一。然而,数据显示,具有合理回报率的节能新产品的扩散速度往往非常缓慢,这种现象被称为"能源效率缺口"。检验能源效率缺口的最常用方法是估算消费者在选择节能产品时的隐含贴现率。本文以热水器为研究对象,通过在南京市开展基于陈述选择实验的问卷调研,搜集了消费者关于不同类型热水器选择的陈述偏好数据,在此基础上构建了离散选择模型,对消费者选择热水器的隐含贴现率进行了估计。研究发现:1消费者在电热水器、燃气热水器、太阳能热水器和空气能热水器之间进行选择时,平均隐含贴现率为30%,远高于其资金的机会成本,说明存在能源效率缺口。2在其他因素相同的情况下,被访者受教育程度越高,隐含贴现率越低,小学学历的被访者隐含贴现率为51%,而大学本科/大专学历的被访者隐含贴现率为22%。3在其他因素不变的情况下,被访者家庭收入越高,隐含贴现率越低,家庭年收入在15万元以下的被访者隐含贴现率超过30%,而家庭年收入超过30万元的被访者隐含贴现率仅为5%。4信息不完全可以导致能源效率缺口,在平均收入和平均教育水平的情况下,没有看过空气能热水器广告的被访者的隐含贴现率为42%,而看过空气能热水器广告的被访者隐含贴现率仅为16%。
Residential energy consumption is one important component of the total energy consumption. With the increase of households' living standard and the expansion of urbanization,the residential demand for energy will increase continuously. To stimulate the adoption of energy efficient appliances is one of the important ways to promote household energy conservation. However,the diffusion speed of cost-effective new energy conservation products is usually very slow,which is called ‘energy efficiency gap'.The most common way to testify the existence of energy efficiency gap is to estimate the implicit discount rate in consumers' purchasing choices. This paper carried out a survey based on stated choice experiments in Nanjing and collected stated preference data on consumers' choices on water heaters. A discrete choice model was specified and the implicit discount rate was estimated. The results showed that: 1 the average implicit discount rate in the choice between electric,gas,solar and air water heaters was 30%,significantly higher than the opportunity cost of the capital,indicating the existence of energy efficiency gap. 2 Other things being equal,the more educated the respondents are,the lower the implicit discount rate. The implicit rate for respondents with only primary school education was 51% while for respondents with bachelor's degree the implicit rate was 22%. 3Other things being equal,the higher household income of the respondents,the lower the implicit discount rate. For respondents with annual household income less than 150 000 RMB the implicit discount rate was over 30% while for respondents with annual household income over 300 000 RMB the implicit discount rate was only 5%. 4Incomplete information may lead to energy efficiency gap. At the mean level of annual household income and education,the implicit rate for respondents that had not watched the advertisement for air water heater was 42% while for those that had watched these advertisement the implicit discount rate was only 16%.