EXCLUSIVE - EU energy plan threatens carbon billions - source | Reuters

(Reuters) - The Europe Union's carbon market could be flooded with excess permits over the next decade, collapsing prices and depriving governments of billions in budgeted revenues, EU sources say.
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But an overlying mandate for energy efficiency will reduce demand for permits -- by about 400 million tonnes in 2013-2020, one EU source said -- leaving them swilling around in the market, and exerting downward pressure on prices.

"The energy services directive could potentially wipe out billions of euros for governments across the EU, unless EU ETS allowances are set aside," said Sanjeev Kumar at environment consultancy E3G.