Over Grid Connection of Large Photovoltaic Power Plants in Romania

Modern world runs on energy. Energy is the raw material needed to power the engine of economic development for any country in the world. Today it is worldwide recognized that using nonrenewable sources is changing the Earth's climate in a negative direction. Given these climate-change threats, renewable energies appear to be the wave of the future. European States, including Romania, introduced programs for limiting CO2 emissions and supporting renewable energy development. Renewable based power plants, such as photovoltaic (PV), wind and biomass have flourished all over Europe and around the world. New interconnections requirements for utility-connected power plants based on renewable sources are coming into force in European countries, responsible for supporting the grid operation and stability. This paper presents an example of technical compliance certification test procedure of a large photovoltaic power plant. The mandatory technical conditions and the tests carried out in order to certify technical compliance with national regulations are describe and illustrate. Practical results illustrating the photovoltaic power plant behavior are presented. This example may be configured as a tutorial chapter for specialists in the field of power systems engineering interested in designing, powering, connecting to the grid and operating photovoltaic power plants.