“Recent wind towers 100-m tall are the new norm,” remarked an attendee at a recent wind conference. Towers are likely to reach even higher in coming years. That’s good for power production but not so good for the techs who must climb the towers to service equipment. It makes sense that in addition to a safe ladder with fall protection, most towers should also have a service lift that makes it safer, easier, and faster for the technicians to get up and down tower. Service lifts (they are technically not elevators) in wind-turbine towers must be approved by authorities, as are elevators in buildings.
Several states have required that service lifts in wind-turbine towers meet the same requirements and standards as elevators in buildings. Therein lies a problem. “It’s not possible,” says Avanti Wind Systems General Manager Kent Pedersen. “For example, there are a lot of welds in elevators and elevator shafts in buildings. In a wind-turbine tower, however, the lift is cable driven and guided because the tower must have as few welds as possible for the sake of its safety and structural complexity.”
This is one reason members of National Association of Elevator Safety Authorities (NAESA) from several central-region states attended a seminar regarding safety of service lifts in wind-turbine towers. The purpose of the seminar was to introduce elevator inspectors to the wind industry and expose the wind industry to existing and new elevator compliance. More than 40 certified elevator inspectors participated.
Currently, several states follow rules that say an elevator inspector must give official approval before a service lift is used in a wind tower. “Consequently, it’s important for inspectors to know the safety considerations and training that we provide for our lifts and ladders,” says Pedersen. “They should know the difference between an ordinary elevator in a building and the details of a service lift in a wind tower,” he says.
Requirements for service lifts in wind turbines vary from state to state, but a new national standard in a final review stage is expected to take effect in 2012 or 2013. Once adopted, the new standard will ensure the same requirements nationwide. “More importantly, it will further enhance the safety of the technicians working in wind-turbine towers,” says Pedersen.
The coming standard was a big part of the discussions and presentations at the seminar. Most states require an approval of every service lift before it is put into use. The lift must be tested by a certified inspector and it must be inspected at least once a year like other safety equipment in wind-turbine towers. This is done by lift manufacturers such as Avanti Wind Systems, technicians authorized by the company, or a certified inspector. Anyone working in wind-turbine towers should meet the safety rules issued by authorities and owners of the wind farm. This also applies to official elevator inspectors. WPE
By: Kent Pedersen of Avanti Wind Systems, www.avanti-online.com
Filed Under: O&M, Policy, Safety