The hydro turbine supplies 2.5 GWh of energy annually, which provides an income to Scottish Water, supports its net zero targets and leads to lower operational costs. The energy from the turbine supplies the equivalent of 1040 homes each year.

RWGM, a joint venture between WGM Engineering and RSE, carried out electrical engineering for Scottish Water to replace the power supply to the access equipment in the turbine room. Supporting across project management and technical delivery, RWGM ensured the safe delivery of the works in compliance with environmental and ecological standards.

Crane access to the turbine room provides entry points for engineers to maintain the infrastructure in serviceable condition. WGM Engineering project manager Tommy Skelding explained that the age of the operating power bar meant that it was no longer compliant with regulations and had to be replaced.

Tommy Skelding said: “The turbine room had a three-phase power source to operate its overhead cranes. This power line was installed when the dam was constructed and posed a serious risk of electrocution in operation, as the power bar was exposed on the ceiling of the turbine room and was therefore in critical need of replacement. An AKAPP system was installed to replace this.

“This is beneficial to the client because it is an enclosed system, making it safer in operation and weather resilient. The AKAPP system is a way to safely deliver electric power to moving machinery, like the cranes used in the turbine room. A series of power rails remain connected to the machinery via sliding contacts, so that as the machine moves, the connectors remain in contact, providing a continuous energy supply. The upgrade will make it a more resilient and versatile system to support the continued operation of the turbine for many decades.

“The successful installation of this electrical system is a significant milestone in delivering an innovative approach. By replacing the old open busbar with a modern concealed track system, the reliability and safety of the system has not only been enhanced but also delivers a cutting-edge solution for Scottish Water that enabled the turbine to remain operational throughout. The continuous copper strips and double collector design ensure seamless performance, reducing the risk of phase drops and protecting against environmental factors such as dust, humidity and corrosion.”

Delivering a project that involved high voltage electrics had considerable safety concerns. Tommy Skelding explained: “Working with electrical equipment of the type installed in hydroelectric turbines has notable risks, including electrical shock, arc flash and equipment failure. To mitigate this, strict lockout-tagout procedures were followed, all staff received high-voltage safety training and rigorous testing and inspections were carried out before energising the system.”

The Glen Finglas dam is located within the Great Trossachs Forest National Nature Reserve near Loch Lomond in Stirling. With its location inside the nature reserve, it is surrounded by forest and local wildlife.

Tommy Skelding added: “Prior to work commencing on the turbine room, ecology studies carried out by Scottish Water identified 500 protected soprano pipistrelle bats roosting on the site. Maternity and non-breeding roosts of bats were found in the cavity wall of the building and within the building’s interior roof. This discovery directly informed the approach to the upgrade work to ensure the bat population was undisturbed for the full duration of the project.

“A European Protected Species Licence was obtained from NatureScot to approve the works and Scottish Water’s ecology team conducted toolbox talks with the six WGM Engineering technicians ahead of the work, to ensure all engineers were working safely around the roosts, ensuring no harm came to the animals through the duration of the work.”

Scottish Water energy team manager Craig Webster, commented: “The work carried out on the overhead crane by engineers at RWGM ensures that the new system is safe to use for a number of years to come. Finding a solution that meant the busbars were no longer exposed ensures the safety of our own engineers when carrying out any maintenance tasks that require the use of the overhead crane. Having access to this new system supports our work to protect the health of this valuable asset and ensures it is resilient into the future.”