Multi-criteria decision aiding to support stakeholder engagement in the electric transmission planning

To meet the European 20-20-20 targets and the objective of a largely decarbonized energy sector by 2050, a considerable expansion of the electric transmission grid is considered necessary for a largescale integration of renewable energy sources. At the same time, transmission lines can have environmental and socio-economic impacts during both the construction and the operation phases. This can lead to opposition from stakeholders and citizens, and therefore slow down or block the authorization and realization process. Within the INSPIRE-Grid project, co-funded by the European Commission under the 7th Framework Programme (www.inspire-grid.eu), we propose Multi-Criteria Decision Aiding (MCDA) as an approach to support grid planning processes. Energy planning is a field that is quite suitable for MCDA methods because it is subject to many sources of uncertainty, long time frames and capitalintensive investments, along with featuring multiple stakeholders and conflicting criteria. We structured a criteria tree to assess transmission alternatives, considering three main areas: (1) monetary costs, e.g. investment, operating, maintenance and decommissioning costs; (2) environment and health, e.g. air pollution, biodiversity, landscape, land use, noise, GHG emissions, electromagnetic fields; (3) socio-economic aspects, e.g. impacts on economy (agriculture, tourism, etc.), property values, security of supply, electricity prices, transmission grid losses, etc. We used an additive value function under imprecise information, using variable interdependent parameters subject to constraints. Within this framework, a precise elicitation of the trade-offs between the criteria is not necessary; therefore, stakeholders were asked to rank the criteria and, when sensible, to specify additional information about the relative importance of the criteria. The proposed approach was used in two Norwegian real cases, i.e. the realization of the Bamble-Rød and Aurland-Sogndal lines, where we elicited the preferences of different stakeholders with the support of the national transmission system operator, Statnett. The interaction with the stakeholders was conducted in one case with single interviews, in the other one in a group discussion. 84th Meeting of Euro Working Group on MCDA, September 22nd 24th, 2016 MCDA made transparent the preferences of all the stakeholders involved (e.g. planning authorities, transmission system operators, citizens) and helped to display the trade-offs among criteria, so that the stakeholders could consider the advantages and disadvantages of proposed alternatives. MCDA cannot claim to unify or synthesize different systems of values, in case of conflictual decision process. Nevertheless, MCDA may allow participants to structure the debate and facilitate negotiation, especially by supporting a climate of confidence and by providing a common understanding of the problem.