The European Commission has approved a Polish scheme to support high-efficiency combined heat and power (CHP) generation.
It found the scheme, which will run until 2018 with an annual budget of more than one billion Polish Zloty (£200m), complies with EU rules since it furthers efficient energy production.
The support system was set up in 2007.
Poland did not consider the system to constitute state aid but notified the EU to obtain legal certainty.
Commissioner Margrethe Vestager said: “The Polish certificates system in support of high-efficiency co-generation of heat and power will increase energy efficiency in power production. This measure will support EU energy and climate goals and is in line with our state aid rules. Europe needs increasingly efficient energy production to help us meet our environmental goals.”