With European delegates preparing to push a low-carbon agenda at the Rio Earth Summit this week, coal-reliant Poland has prevented EU governments from speaking with a single voice in the bloc's debate on a low-carbon energy future.

At a meeting in Luxembourg on Friday (15 June), EU energy ministers debated an energy 2050 road map published by the bloc's executive in December, which sets out the route towards almost zero carbon power generation by the middle of the century.

Poland has repeatedly objected to any language in EU texts pointing towards deeper carbon cuts to guide decision-making for the years following 2020, when the EU is set to meet a binding target of a 20% emissions cut from 1990 levels.

Ministers from 26 EU member countries backed a resolution calling on the European Commission to propose a new policy framework for low-carbon energy up to 2030, but Poland was the only country to oppose the move.

"Poland cannot accept regulations concerning reduction targets after 2020 without reaching a global agreement on climate issues, and technologies reducing emissions at industrial scale are not implemented," a statement from the country's economy ministry said.

The country's reservations concerned the EU's decarbonisation objective, as well as a call for "robust and adequate" carbon pricing, which in its opinion could be seen as an encouragement to artificial support of CO2 emission prices.

Carbon prices on the EU's Emissions Trading System have fallen to record lows below €7 per tonne in recent months, while analysts say prices of 20 to 50 are necessary to spur investment in low-carbon energy.

A spokesman for the Danish EU presidency said Poland's opposition to the resolution would not prevent the bloc from pressing ahead with its low-carbon plans.

"The resolution was supported by 26 EU countries, and that is a clear signal to the Commission that it can start working on legislative proposals for 2030," the spokesman said.

Poland has, however, expressed support for the EU's drive to increase energy efficiency. The European Union reached agreement a day earlier on a law to require governments and utilities to improve energy efficiency and lower the bloc's consumption of fuel.

Poland has also backed the EU’s position at the UN Conference on Sustainable Development in Rio de Janeiro later this week. The EU wants to push global leaders to commit to sustainable energy a green economy, though it faces resistance from both advanced and developing countries to binding commitments.