Tasmania’s hydropower network upgrade clears way for ‘Battery of the Nation’

Australia’s largest generator of clean, renewable energy, Hydro Tasmania will invest AUD 1.6 billion through 2034 to upgrade and modernize its hydropower network, with long term benefits for renewables in the Tasmania’s future energy system.

The forward plan for capital works includes major refurbishments across 10 power stations and five dams.

Major upgrades at the Gordon and Poatina power stations are underway. The 46-year-old Gordon Power Station has an installed generation capacity of between 432 MW and 450 MW, and generates 1,388 GWh per year, while the 47-year-old Poatina Power Station’s generating capacity is 363 MW.

Hydro Tasmania CEO Ian Brooksbank said works of that scale take years of engineering and logistical planning.

The “stator” stationary part of the rotary power generation system at Gordon Power Station weighs 173 tons, for example, and is craned out of position for maintenance, potentially adding another 30 years to its lifespan.

“This is the heaviest lift we do and it’s a rare event, involving two cranes and millimeter-level precision,” said Brooksbank. “These works will extend the operational life of our power stations, improving capacity, reliability and flexibility.”

Brooksbank said the upgrades will equate to more energy out of every drop of water and can be more responsive to fluctuations in demand.

“This will help us to support wind and other renewables in a modern energy system,” the CEO added.

The works complement plans to redevelop the aging Tarraleah Hydropower Scheme and to build pumped hydro at Lake Cethana as part of Hydro Tasmania’s “Battery of the Nation” ambition to add new pumped hydro to its existing hydropower system.

Hydro Tasmania received AUD 300,000 Australian Renewable Energy Agency (ARENA) funding in 2017 to investigate more than 2,000 potential pumped hydro options, which have now been narrowed down to three, including Lake Cethana.

The lake is 56 km south of Devonport and would require a 3,500 m water conveyance tunnel up to 8.5 m in diameter. The hydropower site would have a 600 MW generation capacity, 11-hour energy storage duration, and an estimated cost AUD 900 million.

The chosen site will be built and ready to operate when 1.2 GW of additional Bass Strait electricity interconnection infrastructure comes online.

Brooksbank said Hydro Tasmania must invest in its infrastructure for a new era of Tasmanian hydropower that will help meet the state’s energy demands now and in the future.

The AUD 1.6 billion investment in refurbishments is in addition to the approximately AUD 100 million it costs to operate and maintain the Hydro Tasmania fleet every year.

From pv magazine Australia.