Typically, people trying to live off the grid use lithium-ion battery systems — such as Tesla's Powerwall 2 — to store the Sun's energy so it can be used when it's most needed.
World-first home hydrogen battery system
The Green Energy Storage system is connected to the outside of a user's home: as it measures a sizable 1,680 x 1,240 x 400 mm (66 x 49 x 15.7 inches) and weighs a hefty 324 kg (714 lb), it's not likely anyone's going to steal it.
The system is connected to a home's hybrid solar inverter as well as the water mains via a purification unit. The system utilizes the home's excess energy to electrolyze the water, after which it stores the resulting hydrogen in a patented metal hydride "sponge" at a pressure of 30 bar, or 435 psi.
When the energy is required by the homeowner, the Green Energy Storage system uses a fuel cell to deliver energy into the home, as well as a small 5-kWh lithium buffer battery for instantaneous response.
High cost, high energy output
A phone app allows the user to monitor and control their system, and businesses can run several of the machines at the same time to form an "intelligent virtual power plant" for their higher energy needs.
The system stores 40 kilowatt-hours worth of energy, which is enough to run an average home for two days. This is also three times as much as Tesla's current-gen Powerwall 2.
As the system costs AU$34,750 (US$26,900), it actually costs more than three times the price of a Powerwall in Australia. However, Lavo says the price will drop to AU$29,450 (US$22,800) in the last quarter of 2022, which will coincide with the system becoming available worldwide.
Hydrogen energy benefits, doubts
Of course, the system's reliability, efficiency, and even safety are still open to debate. One wonders what might happen, for example, if a house fire were to reach the system — Lavo does assure though that any leaks would disperse so quickly they wouldn't be a hazard.
In any case, Lavo joins a growing list of companies touting the benefits of hydrogen over lithium-ion batteries as the future of the clean energy sector, due to its abundance and ease of use.