Project Overview

Balnacarn is a 700kW high head scheme located in Glenmoriston, near Fort Augustus. Dulas was commissioned by Dulas Hydro Generation Ltd to deliver the scheme as a turnkey design and build contract. The scheme has one intake and 1.5 km of pipeline. The pipeline passes through Forestry Commission Scotland land and required consideration of future harvesting activity. The intake is fitted with Aquashear Coanda screens and is accessed using a 1.5 km access track that was constructed for the scheme.

Solution

The powerhouse is in close proximity to a domestic property so particular attention was paid to the visual impact and control of noise. To this end a relatively slow turbine and variable speed ventilation system were specified to reduce noise at source. Noise attenuation was a careful consideration in the specification of the doors, ventilation attenuators, building fabric and outfall.

To minimise the visual impact the powerhouse was designed to be as small and low as possible which required the intelligent use of space within the powerhouse to accommodate a large turbine and full coverage gantry.

The scheme is designed with operation and maintenance at the fore and is equipped with facilities for pigging, a full coverage gantry within the powerhouse, lifting davits at the intake, de-watering facilities and safe access provision for routine and occasional maintenance.

The scheme was delivered using an NEC3 Engineering and Construction Contract with Dulas acting as Principal Contractor as well as preparing the full civil, mechanical and electrical design packages.

Key Features

Technical Overview

Power output: 700 kW

Intake

AquaShear Coanda screens type A/B

Turbine

Gilkes twin jet pelton
Generator Marelli synchronous
Control Panel Dulas
Gross head and flow 170m, 550l/s