A lamp hangs in Greenwich east London June 10, 2014. Britain's power network operator National Grid will launch a tender this month inviting big energy users to reduce their electricity demand at ... more 
A lamp hangs in Greenwich east London June 10, 2014. Britain's power network operator National Grid will launch a tender this month inviting big energy users to reduce their electricity demand at times of peak consumption next winter, the company said on Tuesday. REUTERS/Luke MacGregor REUTERS/Luke MacGregor (BRITAIN - Tags: BUSINESS ENERGY ENVIRONMENT) less 
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Reuters | Photo By LUKE MACGREGOR / REUTERS
Tue, Jun 10, 2014 11:01 AM EDT