Until now, when there has been too much wind on the Irish electricity grid, a pro-rata system has operated, with all wind farms curtailed to the same extent and with what are called 'firm' generators - those that have the status of firm access to the grid - provided with some financial compensation for the curtailment they suffer.
The new policy was agreed by regulators Eir Grid and Northern Ireland Electricity at the end of last year.It earmarks recently completed wind farms with non-firm status - those awaiting local grid upgrades - to shoulder 100% of the curtailment burden during periods of excess wind on the grid.
This means that many of the projects developers have lined up and some recently completed projects are suddenly financially unviable. "Any investment needs to be reconsidered in light of the new policy on curtailment," explained Padraig Fleming, the head of regulatory affairs at Bord Gais, which has more than 200MW installed wind capacity in Ireland and a pipeline of about 300MW. "We've looked at one of our projects and under the new policy it would risk facing an annual curtailment rate of 27%."
Until now, wind farms with non-firm status have generally faced low annual curtailment rates in single digits, with the promise of firm status being granted within a few years. ESB's wind development manager Brian Ryan was equally concerned.
"Unless this decision is reversed we will have to reprioritise our build programme to focus on projects with a firm network upgrade date," he said. "For example, we have a project in Waterford that, for a variety of reasons, network operator Eir Grid cannot promise firm generator status to until 2020. On the basis of the old system we could have accepted a low level of curtailment and gone ahead, but with the new system we have to shelve this project."
Windpower Monthly understands that high-level discussions are ongoing between regulators and developers and there are hopes that a revised policy may emerge in a few months' time. "There has got to be some reconsideration by the regulator. We've made investment decisions in good faith, yet this curtailment policy will affect existing projects," said Fleming. "The regulators got this one wrong, even though its intentions were good."