摘要
This paper examines the uncertainty of a new method – the macro life cycle assessment – to analyze the environmental impacts of public policies. The environmental impacts of two 2005–2025 European energy policies (a business as usual policy and a bioenergy policy) were comparatively assessed and their uncertainty was computed. Following the inventory of each source of uncertainty, uncertainty management methods were sequentially applied to manage these sources whenever possible. Results show that the bioenergy policy causes lower environmental impacts in three of the four environmental damage categories (human health, climate change and natural resources), but more significantly in one (ecosystems). The risk of the business as usual policy causing lower environmental impacts is expected to be low. However, current knowledge makes it impossible to account for all sources of uncertainty or implement advanced uncertainty methods for all elements in the cause-effects chains involved in each European energy policy. Current uncertainty management methods are not adapted to the uncertainty of large models such as the macro life cycle assessment. Hence, while current results are promising, further work is required to improve uncertainty management in macro life cycle assessment.