C I R E D 20 th International Conference on Electricity Distribution Prague, 8-11 June 2009 Paper 0569 CIRED2009 Session 4 Paper No 0569 MICROGENERATION IN PORTUGAL – EDP EXPERIENCE AND FUTURE PERSPECTIVES Nuno MELO Ricardo PRATA Rui GONÇALVES Francisco MIRA EDP Distribuição – Portugal EDP Distribuição – Portugal EDP Distribuição – Portugal EDP Distribuição – Portugal nuno.melo@edp.pt ricardo.prata@edp.pt ruimiguel.goncalves@edp.pt francisco.mira@edp.pt ABSTRACT This paper describes the state-of-the-art in microgeneration integration on the Portuguese grid. After describing the legal framework related with the connection of microgeneration with the grid, and the response associated with a recent Decree-Law (DL) enacted to regulate microgeneration integration with the grid, some results are presented concerning to EDP - Distribution’s (EDP) experience in evaluating the operational conditions of microgeneration connected with the Low Voltage (LV) grid. It is foreseeable that the interest of electrical energy consumers in microgeneration technologies will increase, resulting on the integration of these units on a larger scale. Furthermore, technological developments allow the development of smartgrid concepts that will bring new capabilities to electrical grids. EDP aims to harness the full potential of these new realities, building a vision for tomorrow’s electrical grid through project InovGrid. LEGAL FRAMEWORK Independent generation has a long history in Portugal. Nevertheless the legal framework for licensing and interconnection was the same for a generator of 1kW and for a 50MW power station. In 2008, DL 363 entered in force and it was specifically aimed for microgeneration: (1) Easy internet registration; (2) Simplified licence; (3) Standard equipment; (4) Up to 3.68kW, initial tariff of 650€/MWh for Photovoltaic (PV) panels, 455€/MWh for wind turbines, decreasing with total microgeneration installed; (5) Total of 10MW allowed during 2008, increasing 20% each year. This new framework got a very enthusiastic response, with all capacity registered. Afterwards, some difficulties have arisen, related with the lack of adequate equipment and shortage of licensed installers. During 2008 about 3600 microgeneration plants started their certification process and 808 were certified or connected to the public LV grid. Figure 1 shows the distribution of these installations by administrative district in Portugal. Regarding the tariff incentives and the solar exposition in Portugal, as well as the modularity, scalability and low maintenance requirements of the PV systems, this technology meets, by far, the preferences of promoters. Up to the end of 2008, 95% of the units certified or connected to the grid were PV systems, 4% wind turbines and 1% hybrid systems. Figure 1 – Microgeneration in Portugal – Dec.2008 MICROGENERATION FIELD-TESTS EDP’s systematic approach to assess the impact of microgeneration on the LV grid started in 2003, with the Microgrids and More Microgrids projects (projects co- sponsored by EC Framework Programs). In order to predict the impact on grid operation and power quality, some field- tests have been conducted, involving renewable and grid- connected microturbines, operating as Combined Heat and Power (CHP) generators. Microturbine Field-Tests in a Natural Gas Station The first industrial application of a microturbine in Portugal was in a Natural Gas (NG) station to generate the heat and power required by the process of pressure reduction and to export the remaining power to the LV grid. The microturbine of 80kWe, during the first operating months, proved its added-value with ability to operate in grid-connected and island modes and its good performance. The main problems were related to some unexpected mechanical failures, especially due to the technological immaturity of that model. This installation was used by EDP as a test site to start the analysis of the microgeneration impact on the LV public grid. In grid-connected mode, in permanent regimen, as the short-circuit power of that LV grid is quite strong, there were not recorded any relevant impact on the voltage and frequency stability. However, associated to the transition