Lostock Dam Hydro-Electric Plant

Brief description
Retrofitting two hydropower electricity generation sets to an existing outlet dissipater chamber at the Lostock Dam in the Hunter Valley and the construction of an 11kV overhead electric powerline of approx. 300m length from the nearest feeder at the nearby caravan park to the control house next to the dam.

Background:
In the course of investigating the development of renewable energy resources in Australia the NSW State Water Corporation (ABN 21 147 934 787) have assessed the opportunity of retrofitting existing structures such as dams and weirs with hydropower generators.

Location
Lostock Dam, located 20 km North of Gresford in Dungog Shire in the Hunter valley , has been considered suitable for hydropower generation. The Lostock dam, discharge works and control house are owned by State Water Corporation of NSW.

Description
The generation of hydropower at Lostock dam is based upon the usage of releases that are made into the river bed.
Beneath the dam wall there is a concrete chamber of some 6 x 6m base surface which houses two discharge valves (FDC-valves) that release the water into this dissipater chamber where the energy is taken out of the water. From the dissipater the water runs out into the feeder channel that joins the original river bed. (see photos)

Given the relatively small flows and the small size of equipment required to use those flows it has been decided upon installing two individual generation sets both fitted with a small francis turbine and induction generator. The size of those sets is such that they fit on top of the concrete chamber.

To use the flows that normally would be discharged through the FDC-valves the water is being diverted through an offtake right before the valves, lead to the turbines on top of the dissipater and then fed back through draft tubes down into the dissipater chamber where it exits the chamber the same way as when released through the valves. (see drawing) The housings of the generator sets on top of this chamber measure 2.8 in length, 1.6m in width, 1.6m in heigth.

The generators are rated at 110 kW however; maximum output of each individual generator set will be 96 kW, always dependent on the releases determined by the water authority.