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Snowy Hydro Scheme to Potentially Increase Pumped Storage Hydroelectricity Capability

Yesterday the Federal Government announced funding to conduct a feasibility study into expanding the Snowy Hydro Scheme by adding an additional 2,000 MW of pumped storage hydroelectricity. This additional storage was part of the original design of the Snowy Hydro Scheme but considered unnecessary at the time. The feasibility study is scheduled to be completed by the end of 2017 and if the study is successful the upgrade could be completed as early as 2022.

The use of pumped storage hydroelectricity will add additional capacity to the system but no additional energy. It requires nearly double the amount of energy to push the water up to the higher dam than the amount of energy that is created when released into the lower dams. With New South Wales and Victoria suffering from lack of energy it is difficult to see where the additional power will come from to make this efficient.

Pumped storage hydroelectricity presents a number of desirable properties to the current energy market. It is the only true fast start synchronous technology. Wivenhoe pumped storage hydroelectricity in Queensland can go from being completely offline to 500 MW synchronised and providing frequency services in 11 seconds. For comparison, the best gas generator takes 8 minutes to start up and another five minutes to synchronise.

Pumped storage hydroelectricity will also be able to provide frequency control services even while not generating power. By keeping the turbine spinning but not converting to electricity it can be used essentially as a fly wheel while consuming virtually no water.

Hydros (pump storage and otherwise) typically have a normal operating life of around 100 years though truthfully no-one really knows what will make them stop working. They can also store a large amount of energy economically. Unlike a battery which will typically only be able to store energy for 1 to 2 hours at maximum capacity, a pumped storage hydroelectricity generator is only limited by the size of the upper dam capacity.

The other potential benefit of the Snowy Hydro development is in support of Australia’s Renewable Energy Target.  Whilst pumped storage hydroelectricity is not a renewable source of generation, other parts of the Scheme (run of river hydros) is. If adding pumped storage hydroelectricity to the current run of river scheme is considered a major upgrade, the baseline for the run of river could be reset to zero. This means that the Snowy Hydro scheme would generate an LGC with each MWh of generation. This will be equivalent to approximately 6,500,000 extra LGCs coming into the market, or almost 20% of the total target of 33,000 GWh. Perhaps this is part of the Federal Government’s plan behind meeting the Australia’s Renewable Energy Target.