by Brian Reed
MSEG has two strands to its approach to electricity issues in Mallacoota. One is to improve our use of renewables and reduce our CO2 footprint, and the other is to improve the reliability of the service. It is the second of these strands that involves the use of micro-grids, or ‘islanding’. Micro-grids are becoming more common in remote or mining towns, and now often include renewable energy, but Mallacoota would have been an Australian pioneer in ‘islanding’ had we been able to secure funding to proceed with the recommendations of the feasibility study.
Islanding is a type of micro-grid that involves being able to disconnect a site or town already connected to the grid safely when there is a problem. It is most useful in ‘end of grid’ situations such as ours, where most problems occur on the incoming line, rather than locally. Although this has been done overseas, it was a technical and regulatory challenge in our proposal, having never been done before in Australia with a grid connected town.
Islanding Mallacoota if there is an incoming line fault allows our considerable rooftop solar resources to continue to be used (what is more frustrating than to have the power out on a sunny day, and not be able to use your own solar power?). However, an islanded site must be able to supply its full energy requirement at any time, day or night, or there will be brown-outs or worse. Consequently, islanding is only feasible if there is sufficient local generating capacity in place. In our case that means 1Mw plus, 24 hours a day. The original proposal would have provided that, including a large solar component, but it was a large project which would have been reliant on government support, which was not forthcoming at the time.
While we still hope for support for a project of this scale in the future, in the meantime we intend to investigate options for smaller, step by step Community Owned Renewable Energy projects, to address our first strand objective. Any increase in renewables in town helps our community carbon footprint, and the more success we have, the closer we will be to having sufficient local capacity to support islanding. Proof of success in such smaller projects should also improve our chances of ultimately getting support for the cost of islanding.
Islanding can also occur on a domestic/household level with solar and battery storage minimising reliance on the grid. There a few such systems in Mallacoota (including my own), and they are now becoming available in the general commercial market, with improvements in Li ion battery technology.