Power Shift: The Battery Revolution Has Begun
By: Wilson Da Silva
Tags: Energy, Technology, Climate Change, Science, Climate

He’s right. While the complex engineering that drives the grid in Australia (and every other country) may be impressive, it’s based on a concept that was already outdated — and being overtaken by technological changes — when Australia’s interconnected national grid was completed in 1998.

Disruption was coming from many angles: the growing use of renewable energy, like wind and solar, being connected to the grid, adding intermittency; the rapidly falling prices for solar panels, which triggered a boom in solar rooftop installations and made solar farms viable; and the voracious demand for laptop computers, which accelerated the development (and lowered the cost) of energy-dense batteries like lithium-ion, eventually creating a secondary market for large-scale storage. Meanwhile, computers and high-tech electronics in industry and in homes were changing the way energy was used, unbundling what had for decades been a neat and predictable pattern of usage.

Those effects were just beginning in 1998. Twenty years later, the disruption is so immense, electricity grids are having trouble coping.

Take Australia, for example. In 2018, the number of rooftop solar power generators on Australian homes passed two million, compared with just 20,000 a decade before. There are now, on average, six new household solar installations every minute in the country.

In total, 8,900 gigawatt-hours (GWh) of Australia’s power currently is generated from solar rooftops — more than the 8,000 GWh generated by the Liddell Power Station near Muswellbrook in regional New South Wales, once the biggest power station in Australia. Another 766 GWh of electrical energy was produced by large-scale solar farms (versus zero in 1998) and 12,668 GWh by wind turbines, compared with just eight two decades ago.

That’s a good thing, right? Yes — and no. Australia’s national grid was designed to cater for centralised power from large-scale hydroelectric, coal and gas-fired generators. It was created not just to ensure power was easily transferable from one side of the country to another, but also to drive prices lower. If there were too many plants producing power but not enough being used, prices would fall, encouraging the most expensive generators to drop off the grid. Conversely, spikes in demand did the reverse: pushing prices higher and encouraging more generators online, which eventually lowered prices across the grid.

This worked nicely when competition was between big coal, big gas and big hydro. But solar and wind have become such a low-cost way to produce electricity, and are now so widespread, that they have forced prices lower on the grid — and, paradoxically, higher.

Australia’s national electricity grid, consisting of 40,000 km of transmission lines and cables supplying 200 terawatt hours of electricity to five of Australia’s six states — around 80% of the country’s consumption .(Australian Energy Market Operator)

When solar and wind generators are in operation, they are so cheap that large-scale coal and gas cannot compete, so these dial back production or shut down. However, power from renewables is intermittent — it can rise and fall with little warning, such as when winds abate, or clouds diminish the intensity of sunlight falling on solar panels. Hence, if supply falls off suddenly, and demand stays the same, prices on the grid spike up to encourage more generation and avoid blackouts. That brings the big generators back to cash in.

Problem is, these coal and gas behemoths are inflexible; they take from several hours to a whole day to go from standstill to full power. Even when running hot, they cannot easily or economically vary output up or down fast enough to meet sudden peaks in demand, such as during a heatwave.

Because all generators on the Australian grid are paid for the power supplied in five-minute blocks (known as the spot price), the price of electricity sold on the national grid can vary wildly — on rare occasions, as high as A$14,000/MWh, and as low as minus A$1,000/MWh. But prices stabilise over the year. The average spot price in 2018 was around A$111/MWh in South Australia and A$100/ MWh in Victoria, for example.

Nevertheless, it’s obvious that energy storage is the missing link in this whole shebang. It would allow the power generated by any technology — solar, wind, coal, gas — to be amassed when demand is low, and discharged when demand rises.

And it’s not like energy storage isn’t used. Globally, there are 70 dams, with a generating capacity of at least 2,000 MW each, where water is stored then released gradually to drive turbines and generate electricity. But hydroelectricity, while renewable and flexible, is enormously costly (monetarily and environmentally) to build, and limited by geography and access to reliable sources of water. While those 70 dams have a total energy output of more than 1.2 million GWh, they required the flooding of more than 70,000 square kilometres of land to create them.

“There was a huge lack of imagination,” recalls Skyllas-Kazacos of her discussions with industry giants in the 1990s, when she was trying to commercialise the VRB patents she’d taken out for her employer, the University of New South Wales (UNSW). “People in the electricity sector didn’t seem to be aware of what technology was out there. But also, everyone was looking after their own interests, unfortunately. They weren’t looking at the big picture.”