Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies , 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan.
Environ Sci Technol. 2015 Feb 3;49(3):1738-43. doi: 10.1021/es505245q. Epub 2015 Jan 17.
Product lifespan estimates are important information for understanding progress toward sustainable consumption and estimating the stocks and end-of-life flows of products. Publications reported actual lifespan of products; however, quantitative data are still limited for many countries and years. This study presents regional and longitudinal estimation of lifespan distribution of consumer durables, taking passenger cars as an example, and proposes a simplified method for estimating product lifespan distribution. We estimated lifespan distribution parameters for 17 countries based on the age profile of in-use cars. Sensitivity analysis demonstrated that the shape parameter of the lifespan distribution can be replaced by a constant value for all the countries and years. This enabled a simplified estimation that does not require detailed data on the age profile. Applying the simplified method, we estimated the trend in average lifespans of passenger cars from 2000 to 2009 for 20 countries. Average lifespan differed greatly between countries (9-23 years) and was increasing in many countries. This suggests consumer behavior differs greatly among countries and has changed over time, even in developed countries. The results suggest that inappropriate assumptions of average lifespan may cause significant inaccuracy in estimating the stocks and end-of-life flows of products.
产品寿命估计是了解可持续消费进展和估计产品存量和报废流的重要信息。文献报道了产品的实际寿命；然而，对于许多国家和年份，定量数据仍然有限。本研究以乘用车为例，提出了一种估计耐用消费品寿命分布的简化方法，对消费者耐用消费品的寿命分布进行了区域和纵向估计。我们根据在用车的年龄分布估计了 17 个国家的寿命分布参数。敏感性分析表明，所有国家和年份的寿命分布形状参数都可以用一个常数来代替。这使得简化估计不需要详细的年龄分布数据。应用简化方法，我们对 20 个国家 2000 年至 2009 年乘用车的平均寿命趋势进行了估计。国家之间的平均寿命差异很大（9-23 年），而且许多国家的平均寿命都在增加。这表明消费者行为在国家之间存在很大差异，并且随着时间的推移发生了变化，即使在发达国家也是如此。研究结果表明，对平均寿命的不恰当假设可能会导致在估计产品存量和报废流时产生重大误差。
