Extensions of the production tax credit (PTC), which the wind industry needs to avoid a collapse in 2013, and the Treasury grant programme, key for the solar industry, were left out of a bitterly fought bill to preserve a payroll tax cut, unemployment insurance and other measures for a mere two months.

The short extension means the issue will top the agenda when lawmakers return to Washington DC this month, giving renewables backers another chance to win the support they need.

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