Ambassadors to Sofia of thirteen European states, China and Korea have voiced serious concerns over Bulgaria's government policy on renewable energy.

In a letter to Economy and Energy Minister Delyan Dobrev, obtained by the opposition Glasove newspaper, the envoys protest vehemently against the electricity regulator's decision to introduce grid access charges on all operating renewable energy producers.

According to them with this decision Bulgaria risks to drive away foreign companies, considering investments in the country in many sectors, not only those dealing with renewable energy.

The ambassadors of the fifteen countries called on Minister Dobrev to immediately undertake steps to restore foreign investors' confidence in Bulgaria.

Their letter comes days after the President of the European Bank for Reconstruction and Development (EBRD) Suma Chakrabarti voiced concerns that those charges have been applied retroactively and without any prior consultations with the sector stakeholders.

"These access charges will mean that most currently operating renewable energy generators will immediately become unviable and will be unable to repay their loans," reads Chakrabarti's letter to Bulgaria's Prime Minister Boyko Borisov.

"This raises broader concerns among all investors about the reliability of contracts and the predictability of the Bulgarian business environment," it points out.

Earlier this month Bulgarian renewable energy producers threatened to notify the European Commission that the recently introduced grid access fee constitutes unregulated state aid to power distributors.

Renewable energy producers and industry representatives have staged a number of protest rallies over the grid access fee in front of the headquarters of the State Commission for Energy and Water Regulation (DKEVR) in Sofia.

The protesters demand the resignation of DKEVR Chair Angel Semerdzhiev from the parliamentary committee tasked with supervising the watchdog's activity.

Renewable energy producers say the fee for accessing the networks of the three power distributors operating in the country will deprive them of 10-40% of their revenues and will lead to numerous bankruptcies.

The complaints have already been submitted with the Supreme Administrative Court (VAS).

A number of renewable electricity producers have threatened they will not sign the contract supplements with the power distributors concerning the grid access fee.

The DKEVR Chair commented that the move was illegal, saying that the renewable electricity producers had to be disconnected from the grid.

The protesters struck back, saying the chair of the energy watchdog had no such powers.