Bear Mountain has been installed more quickly than any other wind power project I‘ve ever seen,“ says ENERCON civil engineer Nils Wingert who is based in Lethridge, Alberta. The wind farm is located 15 kilometres south-west of the town of Dawson Creek in western Canada.
Due to the limited space on the ridge of the mountain range and the steady brisk winds, single-blade installation had to be used for all 34 wind turbines. A narrow-track crawler crane proved to be of invaluable help during installation. At only four metres, its track width was not even half that of the second, conventional crane.
“After finishing work on one turbine, this crane could overtake the other crane and be ready at the next available tower within half a day,” explains Wingert. Setting up and dismantling the conventional crawler crane, on the other hand, took the teams two days at some sites. The conventional and the narrow-track crane were working in parallel on all installation tasks from tower construction to single-blade installation.
At the temporary storage area, small mobile cranes supported the teams with the pre-assembly work such as mounting trailing edge sections to rotor blades. “We used the just-in-time approach to deliver rotor blades and machine houses to the individual sites,” says Wingert. His co-worker, site manager Jens Trappmann from ENERCON International Support, had tested such a central pre-assembly area for the first time during a wind farm project in Eemshaven in the Netherlands in 2008.
He had to make some adjustments to account for the different conditions on Bear Mountain Ridge. “Even though we were doing single-blade installation, the wind did pose problems. Frequently, the wind speed would be just above the permissible limit,” says Wingert. Once other installation work was complete, the narrow-track crane was therefore also used for blade installation because it was able to continue installation work at slightly stronger winds.
In total, one pre-assembly, two installation and two blade installation teams were at work on Bear Mountain. Each team consisted of two specialists from ENERCON Support, flown in from the German headquarters, and six to eight Canadian technicians. “ENERCON is currently setting up permanent installation teams in Canada. The people working here at Bear Mountain have really proven their worth. Service in Canada could definitely also use them for the long term.”
In addition, a number of Canadian contractors could establish themselves, such as crane company Eagle West Wind Energy, Formula Contractors for foundations, and transport company Salco Energy Services. The project was originally launched by the Peace Energy Cooperative in Dawson Creek, a local renewable energies initiative with 400 members.
It owned the exclusive rights to develop a commercial wind farm in the midst of the local Bear Mountain recreational area (offering skiing, hiking, and ATV riding). For this purpose, the cooperative partnered with Aeolis Wind Power Corporation based in Sydney on Vancouver Island who developed the wind farm further.
In 2006 British Columbia Hydro, the province‘s utility company and grid operator, awarded three contracts for electricity feed-in from wind farm projects in the region: One of them went to the Bear Mountain project. During the development of other wind farms in British Columbia, Aeolis had previously cooperated with the AltaGas Income Trust which specialises in the development and operation of energy generation systems of all kinds.
“In 2007, we acquired the entire project from Aeolis and the Peace Energy Cooperative,” says AltaGas company spokesperson Adrianne Lovric. “Based on their early partnership in this project, Aeolis and the Peace Energy Cooperative receive annual royalties from the proceeds once the wind farm is operational.” Bear Mountain is AltaGas‘ first wind farm.
“Our commitment to renewable energy is driven by market demand for clean energy,” explains Lovric. Its high average wind speeds of 7.6 to 8.2 m/s at hub height (78 metres) and its proximity to the existing grid infrastructure make Bear Mountain the ideal location for a wind farm, says AltaGas.
The construction of the 34 E-82 wind turbines on Bear Mountain Range has been accompanied by an extensive environmental monitoring programme that continues through the turbines‘ first years of operation. Aspects such as geology, hydrology, and water quality as well as the development of wildlife populations (such as the impact on bats) and vegetation are assessed by scientific experts, reports AltaGas.
The monitoring programme is scheduled to conclude about three years after the commissioning of the wind farm. While construction was under way, a large area around the site was closed off for safety reasons. Shortly after the wind farm was commissioned, strollers, hikers, and skiers returned to the mountain tops of Bear Mountain Range, reports ENERCON project manager Nils Wingert.
The entire area except for the fenced-off lots immediately surrounding the wind turbines is once again accessible to the public. AltaGas is going to put up information boards about the project inside the wind farm and will additionally partner with an outreach/interpretive centre in the city of Dawson Creek to offer off-site interpretive information on the wind farm.