The changing shape of wind and solar in Australia’s grid

Australia is currently experiencing an unprecedented boom in solar and wind energy investments, both in terms of capacity and dollars. It will likely take the country to a 33 per cent share of renewables as early as 2020.

But there is another fascinating development taking place – as more and more wind and solar is added to the grid, the shape of their output is also changing, and in a way that should give confidence about a clean energy future based around a high level of variable renewable energy sources.

Two significant trends that are emerging: the first is the offering of “firming contracts” to those looking to source a significant amount of their supply from wind and solar, but wary of wholesale price risks when the sun don’t shine and the wind don’t blow.

The second is the development of projects that do much the same thing but this time by the physical combination of  wind, solar and some form of storage at the one site, or nearby. Proposals and projects are now emerging across the country.

One of the first “solar firming” products came from TFS Green, who helped put together a package for ERM Power that takes the risk out of contracting with a solar farm.

This is a product that simply seeks to manage the risk from variable solar output by providing price swaps. It allows a solar plant to provide a customer with a firm price for a flat load.

Around the same time, AGL launched a wind firming contract (see graph above), while more recently Macquarie was involved in what is called a “proxy revenue swap” for a wind farm in Victoria that will provide “baseload” green power for packaging giant Orora.

These proxy revenue swaps also emerged in two deals done for another two solar farms in Victoria and Queensland. The term sounds complicated and non doubt is, but is essentially a hedging contract.

All of these developments, note analysts at Morgan Stanley, are potentially disruptive because it enables corporates to structure electricity contracts the provide firm power, and match their usage, without having to resort to the big retailers.

That allows innovative renewable energy developers like Simec Zen Energy to contract solar farms, match them with large energy users like miners and manufacturers, and provide firm supply.

Simec Zen has started to do this with 5 of the biggest energy users in South Australia, will extend it to its Whyalla steelworks and other major customers once it builds more solar, battery storage and a pumped hydro facility, and will then take it national with plans for up to 10GW of solar.

CWP, which is building the Sapphire wind farm in northern NSW, and is looking to add both large-scale solar and battery storage nearby, is also considering a move into retailing for exactly the same reason, head of development Andrew Dickson told the Large Scale Solar and Storage conference last week.

And this is where the crossover between contracting and physical delivery gets really interesting.

“We are moving towards our own retail capability in the future,” Dickson says. “We can aggregate and shape products to meet growing needs of industrial users in the NEM, and we can do so at very competitive prices.”

Dickson also agrees with Morgan Stanley’s assessment – shared by the likes of Ausgrid CEO Richard Gross – that the days of a few dominant – are numbered. “That’s not the future,” Dickson says.

Roger Price, the CEO of Windlab, also talks of fully dispatchable renewables – or, to borrow the parlance of the coal lobby, “baseload renewables”, with the Kennedy Energy Park inland from Townsville.

The first stage of this project is being built now, combining 43MW of wind, 15MW of solar, and 4MWh of Tesla battery storage. “Big Kennedy” will likely be 10 times the size, or 20 times the size, depending on local appetite.

“It’s the perfect match,” Price says. “You get solar in middle of the day, the wind resource picks up as the sun starts to set, blows through night, then drops after the solar” emerges for the morning peak.

Tilt Renewables is another looking to combine wind and solar, as well as battery storage, based around its already completed Snowtown wind complex in South Australia.

This graph above was given in a recent presentation that shows the average output for wind and solar – combining the two, and then backed up with some form of storage, enables them to provide a firm contract to customers, without getting pasted by gas generators pushing the wholesale price up to the market cap.

And, of course, there is the Kidston project in North Queensland, not farm from Kennedy, where Genex Power is looking to combine 270MW solar and 250MW of pumped hydro, with maybe 6-8 hours storage, and then add 150MW wind power for good measure.

The output will look like this graph above.

Like the other wind-solar combinations, wind generation is inversely correlated with the solar resources, the pumped hydro compensated for the variability of wind and solar, and Genex executive director Simon Kidston describes it as the world’s “first baseload renewable energy project.”

Except, these are not really “baseload” plants in the true sense, or in what the coal boosters imagine they are, because they don’t need to be.

But they are fully dispatchable, which is what is important in a modern grid. “It is dispatch able renewable energy on demand 24/7,” says Kidston. That includes overnight, and in periods of peak demand. The clean energy transition marches on.