The New York State Public Service Commission (PSC) has closed its investigation into the turbine failure at the Noble Altona Windpark in Clinton County, N.Y.
The decision to close the investigation was based on independent reviews of Noble Environmental Power LLC's records, management protocols, operations and maintenance procedures, and site conditions.
These assessments of procedures and records allowed the PSC to conclude that the Noble facilities have been inspected and maintained in accordance with the manufacturer's recommendations. Moreover, the PSC concluded that Noble has demonstrated that it is in compliance with appropriate specifications and procedures for inspection, maintenance, public safety and site security as required.
‘The commission is mindful that site security and public safety require ongoing diligence and adaptation of procedures as technology advances, and the commission expects Noble to make certain that its electric plant and facilities are secure and that public safety outside of the turbine setback areas is reasonably assured,’ says Garry A. Brown, chairman of the PSC.
Meanwhile, in response to the turbine failure incident, the manufacturer of the turbine has implemented appropriate product and process improvements to preclude a repetition of the circumstances that led to the incident.
On the morning of March 6, 2009, the Noble Altona Windpark experienced the unintended loss of electric power. Two units, designated as turbines 42 and 59, did not move into safe mode upon the loss of power as designed.
The rotor and blades of turbine 42 spun at approximately three times the operational design speed, and blades apparently contacted the tower structure, which ultimately collapsed, according to the PSC. Oil in the nacelle of the turbine caught fire, and the unit was heavily damaged. The blades on turbine 59 also spun freely, resulting in damage to one of the composite blades. Personnel at the site restored electric power to turbine 59 and succeeded in placing it into safe mode before it sustained any additional damage.
As a result of the incident, a Department of Public Service team was established to perform an investigation.