In remote towns, what happens when the sun fails to shine, the wind barely blows and batteries begin to run low?
Author
- Md Alamgir Hossain
Senior Lecturer, Electrical and Electronic Engineering, University of Southern Queensland
Too often, the answer is another costly diesel delivery .
Australia is already investing in regional and remote microgrids, including two First Nations-led microgrid projects in the Northern Territory. Microgrids are small, controllable electricity systems that are powered by renewable energy and can operate independently of the national network.
Meanwhile, the federal government is exploring what opportunities renewable hydrogen may offer. Globally, we consume about 100 million tonnes of hydrogen each year - most of it fossil fuel-based - to produce everything from fertiliser to margarine . But Australia's hydrogen ambitions have been shaken by cancelled projects and high costs. Internationally, uncertain demand and a lack of infrastructure are holding back hydrogen development worldwide.
Our recent study takes a practical look beyond the "hydrogen hype". It suggests hydrogen could work alongside batteries in some remote microgrids.
Not just a replacement
Solar panels and wind turbines produce renewable electricity. Batteries store any surplus energy for later use, making them particularly useful when the sky is cloudy, winds ease or demand suddenly rises.
If more electricity is generated than the battery can store, a device called an electrolyser can split water into oxygen and hydrogen. The hydrogen is then stored and later fed into a fuel cell , which uses it to generate electricity. This allows renewable energy to be stored for longer periods and used when needed.
But this process has its downsides. Converting electricity into hydrogen and back again loses more energy than storing electricity in a battery. Hydrogen equipment is also expensive .
So hydrogen is not a replacement for batteries, but offers another option when longer storage is needed, diesel deliveries are costly, or several days of backup power are essential.
Combining forces
In our recent study , we tested an automatically controlled experimental microgrid. The system used real batteries and equipment that acted like renewable power sources, an electrolyser and a fuel cell.
We examined its performance under different scenarios to assess:
how the electrolyser responded to surplus power
how the fuel cell responded to a power shortage
how the whole microgrid handled changing demand.
Our results showed the system could respond to shifts in supply and demand while keeping the microgrid's voltage close to its target of 380 volts. This is an important step in bringing this technology from the lab to the field.
Australia has also built a related field demonstration. The Denham project in Western Australia is the country's first remote renewable hydrogen microgrid. It became operational in 2024 and was designed to store excess solar electricity as hydrogen for later use.
The Australian Renewable Energy Agency described this trial as a success . But it also identified challenges in delivering the project and making the hydrogen equipment work with other technologies.
Where to from here
Hydrogen microgrids may be most useful in places where reliable power is expensive or difficult to get, such as remote communities, islands and offshore operations. These locations often rely on diesel delivered by truck, ship or barge. And it can be costly to connect these communities to the main electricity grid.
But hydrogen microgrids won't suit every remote community. Producing hydrogen requires purified water. In dry or offshore locations, supplying this water requires extra equipment , uses more energy and increases costs. Communities may also lack the resources or skills to keep electrolysers and fuel cells running.
Communities must first decide what level of reliability they need and what risks they are willing to accept. Possible risks include higher upfront costs, extra pressure on scarce water supplies, and delays in sourcing specialist parts or repairs. They should also consider whether public money would be better spent on another technology, such as larger batteries, pumped hydro or stronger transmission links.
Any proposed microgrid should be designed with local conditions in mind. The European Union's REMOTE project tested three combined hydrogen-and-battery systems at isolated sites in Spain, Greece and Norway. The projects showed technical promise, but each site required a different design to match its energy supply and the needs of local customers.
Hydrogen is unlikely to replace batteries any time soon, but could be valuable in places where longer storage is essential. However, it's ultimately up to communities to decide whether hydrogen is worth the investment - or is just another hyped-up technology.
Md Alamgir Hossain receives funding from the Blue Economy Cooperative Research Centre.
