Snowy Hydro 2.0 – will it ever be built?

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Snowy Hydro 2.0 – will it ever be built?

Abandoned energy policies litter the Australian landscape. The Carbon Pollution Reduction Scheme, Emissions Trading Scheme, National Energy Guarantee: none have survived, nor have the prime ministers that proposed them.

Snowy Hydro 2.0 is the only big initiative left standing with a chance of survival.

It's a multi-billion-dollar, devilishly complex engineering project that aims to put a new underground power station in a remote corner of the Snowy Mountains.

Can it be done? How would it help shore up the nation's electricity supply? And is it worth it?

"The critical thing is engineering and economics," Malcolm Turnbull declared time and time again, spruiking the project in his time as prime minister.

He's been dispatched, but Snowy 2.0 may yet come to fruition.

Engineering

Exploratory works for Snowy 2.0 are due to begin shortly, the first stage in bringing the decades-old idea to life for the modern electricity market.

The original Snowy Hydro Scheme in the Great Dividing Range was the largest engineering project the nation had ever seen, diverting water from high country rivers to generate hydro-electric power and support irrigation.

Snowy Hydro 2.0 revives an old plan to link two of the reservoirs in the northern reaches of Kosciuszko National Park — Talbingo and Tantangara.

When wind and solar farms are generating more energy than needed, that extra power would be used to pump water in Talbingo up through 26 kilometres of underground pipeline to Tantangara. When wind and solar can't meet demand, water would be drawn back down the tunnel through turbines to generate hydro-electricity.

Tantangara lies on a high, open plateau, while Talbingo is at the base of the western slopes of the Snowy Mountains.

The 850m difference in elevation between the two reservoirs is ideal for a hydro-electric power station, but the 26 kilometres between them is not.

It means the power station has to be deep underground. Snowy Hydro's own feasibility study notes "the geological, geotechnical and hydroecological conditions vary significantly along the alignment".

The tunnel would have to pass through five different types of rock, three major fault zones and five rivers and creeks along the way. The soft, porous limestone karst that has shaped the nearby Yarrangobilly Caves could prove to be a technical nightmare.

The exploratory works are critical — they'll determine whether Snowy 2.0 is both feasible and economically viable.

It will involve drilling a tunnel eight metres high and equally wide to assess the rock type and, most critically, reach the possible site of the underground power station.

The power station and its turbines will be housed in an enormous cavern drilled out of the rock 850 metres below the surface of the Kosciuszko National Park.

That cavern will need to be 190 metres long, 55 metres high and 30 metres wide. Imagine the space the Sydney Opera House inhabits, only much narrower.

Stringent environmental conditions are expected to be attached to the Snowy 2.0 project to protect the flora and fauna.

The corner of the Kosciuszko National Park where most of the construction will take place is known as Lobs Hole Ravine. It is not untouched wilderness, but it is beautiful and lonely.

In the late 1800s there was a copper mine, evident today through the network of tracks, mine shafts and some European trees scattered at the site.

The area today is only occasionally visited by adventurous four-wheel drivers and fly-fishing aficionados, but that is about to change. For the exploratory works alone, 750,000 cubic metres of rock will be excavated. Some of it will be used to upgrade roads, but most will end up at the bottom of Talbingo reservoir.

The drilling will require 200 workers living on site. What is currently a grassy valley beside the Yarrangobilly River will become the site of water and sewerage services supporting an adjacent accommodation camp.

Snowy 2.0 would require further environmental approvals if the project advances from the exploratory stage to full construction.

Economics

Snowy Hydro estimates the Snowy 2.0 project will cost somewhere between $3.8 billion to $4.5 billion. Given it will multiply Snowy Hydro's generating capacity by one and a half, the transmission network to distribute the power across the eastern states needs upgrading too, which is likely to cost another $2 billion.

It could end up costing billions of dollars more.

The feasibility study finds "there are risks, opportunities and contingency amounts that significantly affect" the estimated cost. But the entire chapter on the cost estimate has been redacted, deemed commercial-in-confidence.

There is a "radical transformation" underway in how electricity is generated in Australia, according to Australian Market Energy Operator (AEMO).

In the last decade, nearly 7,000 megawatts of baseload generation has been 'retired' from the national electricity market as coal-fired power stations shut down — equivalent to about an eighth of generation in today's network. Between now and 2050, another 16,000 megawatts of generating capacity will be shut down, too.

Rather than being replaced by new coal-fired power stations, electricity companies are investing in either gas or renewable energy. Compared to coal-fired power stations, wind and solar farms are continuing to improve in efficiency, can be built quickly and cheaply, and have comparatively minor operating costs.

In 2017, then-chief scientist Alan Finkel headed an independent review looking into the future security of the national electricity market, including what would happen if energy policy remains unchanged. It found coal-fired power generation would continue to decline, with renewables becoming the biggest supplier of energy, generating more than 40 per cent of all electricity.

That's where Snowy 2.0 fits into the picture. Taking advantage of excess wind and solar energy to store water for hydro-generation later is a process known as 'firming' renewable energy, which makes it a viable alternative to coal and gas for providing baseload power.

The current rate of solar and wind development is "phenomenal", according to Doctor Matthew Stocks from the ANU Energy Change Institute.

"If it continues, we are at 100 per cent renewables by 2030, never mind the targets that are being bandied about," he said.

That would make pumped hydro schemes like Snowy 2.0 essential.

"We've found thousands of sites around the country which will be able to help, along with Snowy 2.0, to stabilise the system," he added.

The future

Snowy 2.0 could be completed by 2025, according to Snowy Hydro, if the economics and engineering unfold as anticipated.

That is, provided Snowy Hydro's sole shareholder — the Commonwealth — gives it the green light.

Both the Coalition and Labor are enthusiastic, but non-committal, until the exploratory works have been completed.

The restraint stems not only from the possible engineering challenges, but also the uncertainties around the future of the energy market.

Another uncertainty is ever-evolving technology of batteries. Currently, batteries such as the 'Tesla big battery' in South Australia can fill the gap between supply and demand for hours, but not days. Snowy Hydro estimates Tantangara could hold enough water to power 3 million households for a week. But if batteries become more efficient and have a longer lifespan, it could change the equation for pumped hydro schemes in the future.

At the moment, Snowy 2.0 meets the needs of an electricity market marching ahead with renewable energy.

Its main booster in Malcolm Turnbull has departed, but Snowy 2.0 may survive the fractious political debate over energy because no-one who remains vociferously objects to it — and in today's political climate that may be the ultimate endorsement for Snowy 2.0.

Credits

Graphics: Georgina Piper

Photography: Melissa Clarke, Mark Moore, others credited

Production: Jackson Gothe-Snape

Topics: government-and-politics, environment, energy, hydro-energy, environmentally-sustainable-business, environmental-policy, environmental-management, environmental-impact, environmental-technology, australia

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