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Those living on islands and in remote communities – such as remote Indigenous communities – can reduce costs, boost electricity stability and increase energy efficiency by installing renewable energy microgrids, according to a new casebook from the Rocky Mountain Institute and Carbon War Room.

Renewable Microgrids: Profiles From Islands And Remote Communities Across The Globe profiles 10 islands and remote communities that are “actively embracing” renewable microgrids in order to encourage other communities to “make the switch away from oil to efficiency and renewables”.

According to the authors, remote communities are “disproportionately dependent on oil for their well-being”, as they need it to power electricity, fuel boats and trucks that import goods, and support the tourism industry in the local area.

However, the researchers argue that solely relying on imported oil for small-scale electricity generation can expose theses communities to several risks, such as high costs (the average Caribbean nation pays three times more in retail electricity prices that the continental US), price volatility and reduced energy security due to the threat of supply interruption.

As such, the Rocky Mountain Institute and Carbon War Room report showcases 10 communities that have already transitioned to electricity systems with “significant renewable penetration”, including wind power, solar energy, hydro energy and energy storage microgrids. These have reportedly led to “operational cost savings, reliable and stable power, long-term energy price stability and reduced dependence on oil”.

Australian case studies

Three of the 10 examples refer to remote communities in Australia.

For example, the 1800 residents of King Island, Tasmania, receive 65 per cent of their electricity from renewable sources. Driven to change by the fact that the cost of producing power from diesel generators alone exceeded Hydro Tasmania’s revenues, the utility company built a wind farm incorporating a dynamic resistor, two flywheels and a battery to help meet the island’s electricity needs. The system has reportedly reduced carbon emissions by more than 50,000 tonnes to date, while improving reliability and power quality. The average rate for power is now $0.19 per kilowatt hour.

Hydro Tasmania is also experimenting with biodiesel blends in order to further reduce the amount of oil used to produce electricity on King Island.

Mircrogrids could also benefit remote Aboriginal communities, the report states, as showcased by the communities of Marble Bar and Nullagine In Western Australia.

In 2008, the utility company Horizon Power used a government grant to help finance a 508-kilowatt microgrid system that utilises single-axis tracking solar photovoltaic technology, diesel generators and a kinetic flywheel (to enable the grid to operate on very high penetrations of the local solar resource when it’s sunny and ride through short fluctuations, such as cloud cover) to produce around 30 per cent of the community’s annual power needs.

Although this system results in parasitic losses (due to the fact that the flywheel must continue spinning at night in order to maintain overall system operation) and has not reduced electricity rates, the power system is said to now be “more reliable” and will enable the community to hedge against increasing oil prices.

The last case study in Australia looks at how electricity is generated for the 140 people living in Coral Bay, Western Australia. In 2006, the fishing community decided to move away from using individual generators to generate electricity using a hurricane-proof wind-powered microgrid – which generates 45 per cent of the annual electricity capacity – and low-load diesel generators and flywheel. Although there’s no baseline to compare electricity rates directly (since there was previously not a connected system), the cost for individuals has reportedly gone down since residents are no longer paying for fuel to run their own generators.

Other examples cover communities in the Netherlands, UK, US, Spain, the British Virgin Islands and Antartica.

From studying these communities, the authors identified three challenges to remote renewable energy microgrids: maintaining grid stability from intermittent renewable energy resources; the cost and logistical challenge of installing equipment in remote locations; and the complicated bureaucratic process involved to gain government grants and utility equity.

It therefore highlighted several “lessons learned” to “help guide decision making within communities currently considering a transition from oil to renewables”.

These were: reducing costs is “not always a straightforward process” but transitioning to renewable microgrids can reduce diesel costs and operating costs; microgrids with diverse resource mixes are less prone to system failure than microgrids that rely on a single resource (as they have multiple resource options for electricity generation); relying on local resources, and less on imported oil, increases overall resiliency for a community; remote communities should boost energy efficiency measures (such as installing LED lighting, adding insulation and choosing energy-efficiency appliances) as they are “more cost effective than any generation option”; and systems should utilise energy storage (such as flywheels, batteries or pumped hydro energy storage systems) to make communities more resilient.