Decarbonization of the Electrical Power Sector in Europe: An Asset, An Opportunity or a Problem?

Climate change has become a priority issue since the beginning of the '90s, but binding agreements on GHG (Greenhouse Gas) emission reduction valid worldwide have not been reached yet. The European Union has been a forerunner on regional binding targets with its “20-20-20†Climate and Energy Package approved in 2009, followed in Dec. 2011 by more ambitious targets implying a dramatic reduction by 2050 of GHG emissions to 80–95% below 1990 levels. After a review of the present world situation with respect to primary energy resources, electricity production and CO 2 emissions, the paper addresses the present and foreseen penetration of the power generation from RES (Renewable Energy Sources) in the EU (European Union), underlining also the economic impact on final clients caused by generous feed in tariffs. The impact of a substantial increase of RES generation both in power and energy on the power market operation and system reliability and security are presented with practical examples from the Italian situations; e.g.: distortion of the day-ahead power market prices, critical load following requirements for conventional plants, need for additional reserve and risk of excess of non-programmable generation (“overgeneration†) in some hours, risk of dynamic stability and worsening of power quality. The main solutions to overcome the above problems are reviewed and a methodology developed by CESI is described explaining how to attain the maximum share of RES generation in a specific power system, in compliance with reliability and security standards. In authors'opinion, the technical and economic aspects must be treated together and it is mandatory to arrive quickly at agreed costs for the environmental impact of electrical infrastructures, particularly CO 2 and other GHG emissions. Coherently, new RES generation and related network assets must be planned in an appropriate way to be a real asset and not a problem.