The average waiting time to procure a permit for construction of a wind park in the European Union is around 42 weeks, the European Wind Energy Association (EWEA) said in a report on its website.

Bulgaria fares considerably better than average, as the time required for consent is just 23 months while Finland enjoys the most "relaxed" regime, with a waiting period of only eight months. The Finns are followed by Austria (10 months), Romania (15 months) and Italy (18 months).

According to the EWEA report, the EU comparisons shows that Finland, Italy, Belgium and the UK are among the fastest countries in which to obtain a permit, whereas Spain and Portugal are among the slowest. Differences in waiting times can be explained by the idiosyncrasies of each case and are not uniform, but among the factors thought to explain the variations are red tape,  the number of authorities to be consulted and the lack of clear administrative guidelines for developers, the report said.

The data was disclosed by the EU-funded project, Wind Barriers, coordinated with EWEA.

The countries whose system could be described as perhaps the most cumbersome in the EU are Spain with (57 months), Greece (50 months) and Poland (43 months) respectively.

"If Europe is serious about reaching 20 per cent renewable energy by 2020, some member states need to streamline their consent procedures for wind farms," Justin Wilkes, EWEA policy director, said in the report.

"There are a number of actions all member states could take: creating a one-stop shop approach for contacting the different authorities, writing clear guidelines for developers, and introducing better and streamlined spatial planning procedures. Implementation of the Renewable Energy Directive provides a real opportunity for targeted action in certain EU countries," he said.