You can get anything at Ikea, much of it flat-packed for a convenient trip home in the hatchback. (We’ll gloss over the relative inconvenience of assembly.) On the back of this year including solar PV and battery storage as part of its home improvements line to consumers, the Swedish mega-brand has announced its serious intentions to rely on clean energy to power its outlet in Adelaide.
The site near Adelaide’s airport will become the country’s largest grid-connected commercial microgrid, with the $6.6 million first stage of the project relying on 1.2MW of rooftop solar and a 3MW/3.4MWh lithium-ion battery storage system.
By the middle of next year the new microgrid will be supplying about 70% of the voluminous furniture shop’s electricity needs, delivered via a power purchase agreement with Epic Energy. It’s a great leap up from the 30% range achieved at most commercial PV projects, thanks in part to the enormous battery capacity – to be housed in three 40-foot shipping containers – but also due to an energy management system that overcomes the problem of exports pushing up voltage levels in the network.
Planet Ark Power’s eleXsys technology is designed to accommodate grid-connected solar in parts of networks where reverse power flow is reaching problematic levels, because of nearby high penetration of PV.
“When you get to about 20% of the feeder’s capacity, you end up with voltage problems,” says Planet Ark Power chief commercial officer Jonathan Ruddick. “The grid was never designed to take large amounts of reverse power flow.”
Between the lines
Because operators of distribution networks are obliged to keep voltage levels within a determined range they are left with two choices, Ruddick says: curtail solar systems on parts of the network where there are voltage issues, or upgrade the infrastructure. In South Australia, where rooftop PV can on some afternoons be classed as the largest generator in the state at 1.5GW, SA Power Networks has been tasked by the government and AEMO to manage output of new PV systems in times of stress.
For commercial and industrial PV systems, the large majority are limited to zero exports to be granted connection to networks. “There is a lot of congestion out there,” Ruddick says. “It’s happening all over Australia.”
The eleXsys system was invented by Planet Ark Power CEO Bevan Holcombe to get around this problem behind the meter by “sinking or sourcing VARs” to manage the voltage of the generating assets, be they modules or batteries.
The Ikea project will be a great demonstration of the technology, Ruddick says, although it has already been trialled at a car dealership in Queensland and its inventors awarded the Intelligent Grids, Platforms and Cyber Security prize at the Startup Energy Transition Awards in Germany in 2019.
Over the line
The designers of the Adelaide Ikea project had hoped for 3MW of storage and 1.2MW of solar, on separate connections. SAPN, however, limited battery export to 2.7MW. This limited the economics of the investment, because the owners wanted to use the battery to trade not only the spot market but also the FCAS markets, which are only available in 1MW chunks. This essentially limited a hoped-for 3MW of trading capacity to 2MW. On that result, “the whole project economics were affected,” Ruddick says. “It wouldn’t have the same business case.”
It’s the inclusion of the eleXsys tech, which gets its own 20-foot container, that has made the project feasible, he says. “It means we can provide frequency services, which is more and more in demand as the grid is connected to more and more distributed solar.”
Ruddick sees it as a “circular” relationship, where fixing the voltage problems enables more distributed solar, which leads to more frequency problems, which can be managed – for a profit – by batteries, to stabilise and provide security to the network.
“We’re able to increase the bandwidth, if you like, of the electricity network to host more and more solar,” he says, estimating about 200% of current hosting capacity of the feeder. “Given rooftop potential, that will easily be enough to meet current energy demand.”
In the box
Smart software in separate eleXsys units housed with the batteries will control the FCAS trading, he says. All the units will remain the property of Planet Ark Power and operate on a fee-for-service basis. Use of silicon carbide semiconductors allows the tech to operate at very high frequencies and high voltage levels, allowing for smaller, lighter, more efficient equipment, he says. Instead of taking up the space of about six refrigerators, the units are about the size of two desktop computers.
The first stage of the Adelaide Ikea project is due to be finished by August 2021, and Ruddick expects more of the same work to pop up at other Ikea outlets alongside work for property groups that have been in touch. “The [Ikea project] has applications to the whole C&I sector,” he says.
Stage two of the project will see the outlet powered with 100% renewable energy by 2025, including a timber-framed solar array to cover the car park.
In stage three, Ikea and its partners will look into the viability of hydrogen energy being generated on site. In the future there is also the possibility, Ikea says, for it to transform itself into an energy provider that can create and sell renewable energy to the network.