Brent crude futures steadied near 14-month lows, with ample supplies putting prices at risk of further losses as worries over tensions ease.
Ukraine is running low on coal because of violence in the country, according to two firms with energy operations there.
The spill occurred during what Duke described in a statement as a 'routine transfer of fuel oil' at its WC Beckjord plant in New Richmond, Ohio.
The oil and gas entrepreneur says he thinks international oil prices will stay high into perpetuity.
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