Close to One-Third of Oil Shale Goes to Waste
The Environment Ministry's report on the use of Estonia's strategic natural resource oil shale in 2011 notes that while mining output is shy of the maximum permissible amount, companies have been unable to reduce the amount of waste generated in the process.
"Estonia's largely oil shale based energy sector has made a transition at increasing speed to renewable sources. The high amount of losses of this strategic resource and the waste generated are still problems," said Environment Minister Keit Pentus-Rosimannus through a spokesperson.
"It is a concern that the amount of semi-coke and fly ash generated in the processing of oil shale has not been reduced. In 2007, under a million tons of semi-coke was generated, but last year the million-ton threshold was crossed," she said.
Semi-coke still contains enough kerogen to burn, as happened during a flare-up of Soviet-era oil shale waste this year in northeastern Estonia. That pile continues to smolder.
Efficiency has increased since 2010, remaining on par with 2007. Losses were 28 percent in 2007 and 27.9 percent in 2011.
Pentus-Rosimannus noted that only 16 million tons of the maximum 20 million tons were extracted last year, however. And the share of oil shale used to generate electricity has fallen 9.1 percent since 2007.