Collapse of Wind Turbine Investigation Complete; Additional Safety Review Needed

STATE OF NEW YORK
Public Service Commission
Garry A. Brown, Chairman
Three Empire State Plaza, Albany, NY 12223

Further Details: James Denn

james_denn@dps.state.ny.us | 518.474.7080
http://www.dps.state.ny.us 10046/10-E-0149

PSC SEEKS DETAILS FROM WIND FARM DEVELOPER

— Collapse of Wind Turbine Investigation Complete; Additional Safety Review Needed —

Albany, NY—05/13/10—The New York State Public Service Commission (Commission), today received a report regarding Department of Public Service staff’s investigation into the collapse of a wind turbine at the Noble Altona Windpark owned by an affiliate of Noble Environmental Power, LLC (Noble). As a result of the investigation, the Commission will order Noble to show cause why it should not be required to demonstrate, through a third-party certification or otherwise, that its wind farms in New York are providing safe wholesale electric service, and that all quality assurance and quality control program measures and manufacturer’s recommendations for inspection and maintenance of turbines, towers and related facilities have
been implemented for the facilities in New York.

“This Commission takes very seriously its responsibility to ensure that the electric corporations it regulates provide safe and reliable electric service,” said Commission Chairman Garry Brown. “As we continue to encourage and promote development of new wind farms in New York State to help us create greater amounts of renewable energy, we must make sure that those installing and operating wind turbines do so properly, and with all necessary safeguards in place.”

The Commission’s decision today stems from Staff’s investigation into the collapse of a wind turbine at the 65-unit Noble Altona Windpark in Clinton County on March 6, 2009. The investigation concluded that the physical collapse of one turbine, and the failure of another, was the result of certain wiring being incorrectly installed. The incorrect wiring prevented the turbines from going into an automatic shut-down mode due to loss of electric power, which in fact did occur the day of the collapse when contractors changed settings on a bank of relays.

Noble Environmental Power, LLC, the parent of Noble Altona, has 612 megawatts (MW) of wind projects in operation in New York, and an additional 216 MW under development. The firm is the largest wind energy developer in the state. During the course of staff’s intensive and thorough investigation, the wind farm owner was unable to satisfactorily explain why the questionable wiring would have been present in two of its turbines. The investigation also revealed a number of instances where best practices may not have been followed in terms of monitoring operations and where compliance with quality assurance/quality control measures and manufacturer’s recommendations for inspection and maintenance of turbines may not have been fully implemented by Noble.

On a positive note, as a result of the Altona incident, a diagnostic verification program has been created by the turbine manufacturer to detect the presence of the aberrant turbine wiring that had interfered with the safe mode operation. Thus, this particular problem should not recur.

In addition to specific requirements being imposed on Noble, the Commission will be advising those proposing regulated wind farms of its plan to include a certificate condition requiring such companies to demonstrate, prior to facility operation, through a third-party certification or otherwise, that the emergency control system will safely shut down the wind turbine upon loss of power and that the control system meets manufacturer's specifications for the facility. The Commission also expects to include a certificate condition requiring compliance with manufacturer’s recommendations for inspection and maintenance of turbines, towers and related
facilities.

The Commission’s decision (and the staff investigation team's report), when issued, may be obtained by going to the Commission Documents section of the Commission’s Web site at www.dps.state.ny.us and entering Case Number 10-E-0149 in the input box labeled “Search for Case/Matter Number.” Many libraries offer free Internet access. Commission orders may also be obtained from the Commission’s Files Office, 14th floor, Three Empire State Plaza, Albany, NY 12223 (518-474-2500).