Avian-Safe Assessment of Power Pole/Substation at Operating Wind Energy Plants

Wind energy facilities frequently use overhead 34.5 kV (collector) power lines to transfer the power from the plant (turbine) to the grid in conjunction with underground lines as a standard practice for routing power from the... [ view full abstract ]

Wind energy facilities frequently use overhead 34.5 kV (collector) power lines to transfer the power from the plant (turbine) to the grid in conjunction with underground lines as a standard practice for routing power from the turbine strings. Use of these overhead power lines by birds for perching and nesting creates the potential for electrocution. To respond to this issue, the Avian Power Line Interaction Committee (APLIC) developed a series of suggested practices for building or retrofitting power poles with raptor-safe designs and configurations. In 2008, Avangrid Renewables LLC (previously Iberdrola Renewables) adopted these suggested practices for their power lines but subsequent review of its collector system revealed issues in 3 areas: 1) review of 3rd party electrical designs found instances of inadequate covering and /or isolation and misrepresentation of the Suggested Practices (APLIC 2006); 2) inspection of as-built projects found that drawings or engineering specifications with adequate design were not always followed; and 3) assessment of riser poles that transition underground lines to overhead collectors found it was an atypical configuration from utility design with a combination of switches, arrestors, and other equipment that can create avian electrocution risk. To address these areas, Avangrid Renewables initiated an APLIC Conformance project to assess avian risk and recommend retrofits on overhead infrastructure designed to bring the entire operating fleet into conformance with APLIC guidelines. It established a core team to assess avian risk, to recommend and scope retrofit efforts, and to provide quality control and quality assurance (QA/QC) of contractor conducting retrofit installation of existing overhead collector lines and substations. These findings will be presented with additional recommendations on design and construction of overhead power lines and substations at wind energy facilities.