Project Overview

This project involved the refurbishment of the intakes and pipeline of a poorly performing hydro scheme near Kinloch Rannoch in Scotland.
Since Dulas’ refurbishment of the system, the scheme produces 4.5 GWh a year which is enough to power 1,600 homes. The original scheme had venting issues, leading to air becoming trapped in the pipeline, reducing operating efficiency. Both intakes were prone to blocking and required cleaning up to three times a day, resulting in significant lost revenue.

Solution

The refurbishment involved the demolition of the two existing intakes and replacement with new structures fitted with Aquashear Coanda screens. The Aquashear Coanda screens generally only require light manual cleaning once per month and ensure that the plant operates to its full potential. Prior to construction Dulas obtained a variation to the CAR licence from SEPA and section 36 consent from the Scottish Government.

The intakes include various features to ensure that the scheme meets environmental and health and safety standards. This includes protection from floods and erosion, scheme isolation with pipeline protection, safe access for operatives and safe downstream transport for brown trout. In addition to replacing both intakes, Dulas’ refurbishment works included replacing the pipeline air valves and installing pipeline venting at the intake. These improvements ensure that the pipeline operates at full capacity and is protected against collapse. Dulas are now updating the control system and are providing PLC and SCADA support to the scheme owner.

Key Features

East Intake

200m, 260l/s, 3m of ½ height Aquashear Coanda screens

West Intake

350 l/s. 5.5m of ¼ height high capacity Aquashear Coanda screens

Turbine

Canyon 1450kW two jet Pelton
Head 310m
Pipeline 6km of HPPE and ductile iron
Maximum Abstraction 550 l/s