A number of these publications centred on nuclear energy, others however also included different sources of electric power generation. These include Climate Change: Assessment of the Vulnerability of Nuclear Power Plants and Adaptation Costs, Estimation of Potential Losses Due to Nuclear Accidents, Measuring Employment Generated by the Nuclear Power Sector and System Costs in Deep Decarbonisation Scenarios: The Contributions of Nuclear Energy and Renewables. Both the OECD Environment Directorate (ENV) and the IEA have previously worked on external costs (see Chapter 5 for a detailed bibliography). Over the past 20 years, the European Commission (EC ExternE up to 2005, and the New Energy Externalities Developments for Sustainability, the NEEDS studies, between 2004 and 2008) and the Paul Scherrer Institute (PSI, Switzerland) have been among the most active institutions in the field of externality measurement and are important sources of information and methodological competence.