Tham khảo tài liệu 'sustainable growth and applications in renewable energy sources part 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | EU Energy Policies and Sustainable Growth 11 The 20-20-20 Package introduced in 2008 through the Communication COM 2008 30 answers to the call made by the European Parliament about real measures for the transition toward a sustainable development. The Package includes a number of important policy proposals closely interlinked a revised directive on the EU Emission Trading System EU ETS a proposal on the allocation of efforts by member states in order to reduce GHG emissions in sectors not covered by the EU ETS as transport building services small industrial plants agriculture and food sectors a directive on the promotion of renewable energy to achieve the goals of GHG emission reductions. The EU ETS scheme has been a pioneering instrument prior to the 20-20-20 Climate and Energy Package. It is a market instrument that has been already implanted in the US quite successfully and it has been introduced in Europe in 2003 in order to find market solutions to encourage firms cutting GHG emissions. The Cap and Trade system sets a maximum amount of emissions per period 2005-07 and 2008-12 per country. Then each country establishes a national emission scheme and it allocates to firms the emission allowances which could be traded between the companies covered by the scheme. Once the emission permits are allocated firms can trade them within the EU according to their criteria of economic efficiency. In the first and second ETS trading periods 2005-2012 mostly of the EU permits are allocated for free. The importance of the EU ETS scheme is that is has been able to create a market and an artificial price for a public good as clean air. Thus firms covered by the EU ETS have to face costs when emitting CO2 emissions on the one hand a firm that needs for its activity more permits than those at its disposal faces the cost of purchasing them. On the other hand opportunity costs arise because permits could be sold in case of non-production. The 20-2020 Climate and Energy Package has