With all the fuss about the Big Battery, what's happening on the small scale?
There’s a lot of buzz around batteries of late after the Tesla big battery in South Australia defied its critics to show the technology could be used on a large scale.
As operation of the Hornsdale Power Reserve (as the battery is officially known, because it’s next to the Hornsdale wind farm north of Adelaide) nears its first anniversary, it has proven its worth and exceeded the expectations of many, including the market operator.
These grid-scale batteries work by importing (buying electricity to charge up) when prices are low – at times when renewable energy is being generated (i.e. when the wind is blowing, and the sun is shining and exporting (discharging/selling) power when prices are high).
This model is an attractive business model to investors and helps stabilises the grid by smoothing out the expensive peaks and troughs of generation verses consumption.
“The incredibly fast supply response time batteries can provide enables them to provide frequency stability for the grid also,” said John Adley, South Australian Secretary of the Communications, Electrical and Plumbers Union.
As Giles Parkinson at RenewEconomy wrote, the big battery “has given a glimpse of the future, how a grid can be effectively managed with a very high share of wind and solar – not just faster, but also cleaner, smarter and more reliable than the dumb and ageing fossil fuel grid we now depend on, and which has become victim to endless market rorting from the industry incumbents”.
Battery technology is a game-changer – but it’s not all happening on the large-scale. Small-scale domestic battery storage is quickly being taken up in many homes across Australia.
The most widely publicised is the Tesla Powerwall, which will be rolled out, alongside other tech, as part of the 40,000 Housing SA homes as part of the “virtual power plant” model floated by the former state Labor Government.
The first 100 homes had the solar panels and batteries installed in July with another 1000 dwellings to have installs by mid next year.
The former South Australian government adopted an innovative quintessential Labour energy policy of putting PV panels onto public housing to create a virtual power plant that would help bring down the price of electricity for all users by increasing supply whilst helping stabilise the grid and reduce energy cost for low income households.
“When the Liberals took power they initially intended to scrap the plan, but they have since seen the sense in it,” Adley said.
“Unfortunately, the new government has ditched the social welfare part of the scheme and will instead offer subsidies to any households regardless of wealth and capacity to pay.”
The Victorian Labor Government has promised to adopt a similar scheme if it is re-elected in November. It is expected other states will roll out similar schemes to form a country-wide VPP (virtual power plant) to help to stabilise the electricity grids
The sleek lines and fanfare of the Tesla domestic batteries have overshadowed alternatives that outperform the Powerwall, like the GridEdge Quantum battery system that is partially assembled in Australia.
Recognising the potential of the battery market and explosion of renewable energy projects in SA and other states, GridEdge joined forces with Earthworker Cooperative, the Morwell based, worker-owned co-op that is making renewable energy products in the same town as the decommissioned Hazelwood power station.
Using sodium nickel chloride tech, the battery uses heated salt to hold its charge and uses only environmentally friendly and non-dangerous materials in its manufacture and operation.
“Lithium can be unsafe and can explode and catch fire if it gets too hot," said John Ballis of GridEdge.
"And much is currently mined cheap in third-world countries."
Mining lithium can have serious effects on the environment, contaminating the ground and air where it’s extracted from the ground. It’s also used to medicate mental illness, meaning there are serious health implications in many countries where it’s mined where environmental and labour protections are lacking.
"The Quantum is safer than Tesla and all other batteries. Fool proof and safe,” Ballis said.
The salt core of the sodium nickle chloride technology means the battery ccannot catch fire unlike many other technologies have a risk of. It also means the battery can operate without degradation in wider temperature range than most batteries on the market – from -20 to 60 degrees C compared to the optimal 4 to 40 degrees of the Powerwall and similar alternatives. That means it’s better suited to Australia’s wide range of climates while many lithium batteries have been known to kick out in the Top End.
Due to their lack of degradation, the sodium nickel chloride salt batteries can easily be scaled at any time in the future, unlike most other technologies. The sodium nickel chloride batteries don’t need cooled so there is no need for large cooling systems.
Unlike most lithium and lead acid batteries that degrade over time, even when not being used (our smart phones being a prime example), sodium nickel chloride batteries will hold their capacity for years.
“If it’s tuned off, it would still have 100 per cent charge after five years,” Ballis said, adding that the battery is expected to have a lifespan beyond two decades.
Dan Musil of Victoria’s Earthworker cooperative said as well as serious concerns about the extraction process, the “real question that’s still unanswered is about what you do with lithium at the end of its life”.
Currently domestic size lithium batteries don’t have a recycling facility available and people are being charged quite large amounts of money to take away failed batteries. The sodium nickel chloride battery is 100% recyclable within today’s recycling processes.
Earthworker, based in Victoria’s Latrobe Valley, is an environmentally focused work initiative that is backing the clean, sustainable work of companies like Gridedge, which Musil said produce a “really high-quality battery” system.
One product they have worked on is the VoltsWagon, a trailer that combined solar panels a SoNick battery as a “noiseless, fumeless” alternative for diesel generators. This is in addition to the domestic plug-and-play Quantum unit.
And while the batteries are “mostly domestic and small scale” now, Musil sees a lot more potential for them.
In many other countries the sodium nickel chloride technology is already being used in large scale applications to help stabilise electricity grids.
“We think the future for these batteries is a much larger grid scale" for Australia as well, he said.