27 January 2010 – Vanuatu is one of many Pacific island-nations that are extremely vulnerable to predicted sea-level rises due to climate change. It is a very poor nation, by international standards, and one of its biggest challenges is to raise living standards through sustainable economic and social development. Crucial to that transition is slashing the country’s total – and, at present, unsustainable – dependence on imported fossil fuels for energy generation and transport, and cutting its carbon dioxide emissions by using more sustainable energy-generating techniques.

Enter global engineering firm Cundall and a University of New South Wales student, Chris McGrath, who have installed a sustainable hydro-electric power station in Imaki, a small community on the southern coast of Tanna Island, part of the Vanuatu archipelago. McGrath (funded by Cundall) designed a remote area power system (RAPS) for the Imaki community while working with the UNSW School of Photovoltaic and Renewable Energy Engineering in his final year of undergraduate studies.

“The existing energy services supplying the village were poor, with crude facilities supplying the secondary school, church and other amenities,” McGrath says of his first impressions of Tanna Island. “Nonetheless, the community had a basic understanding of the use and potential of electricity, and community consultation identified the primary school as the highest priority for alternate sustainable energy supply.”

This is because a reliable, sustainable power supply would enable students to use computers, overhead projectors and photocopiers, while powering lighting, charging of mobile phones, printing and refrigeration in the school building.

McGrath’s first task was to identify the optimum energy-generating resource, and as local as possible. “After we investigated a number of alternate resources for the system, including solar, wind and even geothermal, we identified hydro as the most appropriate resource to deliver a reliable and sustainable energy source to the community. It was the most cost-effective option that resulted in the greatest energy production capacity,” McGrath says.

An innovative feature of the project was the fact that the hydro resource was the existing water supply. “The hydro system has additional benefits, including lower battery requirements and a positive contribution to a reliable water supply. As the system used existing infrastructure it has a very low impact on the natural environment,” he says. In addition, modelling indicates that a dedicated water pipeline would enable a 1000 per cent increase in power for only a 100 per cent rise in cost.

Implementing RAPS was no mean feat. The team faced a range of logistical challenges, including difficulties shipping materials to the island and having equipment impounded by custom officials.

It was also vital to the success of the project that the community was on board. “This was a project for the Imaki community, so it was imperative to understand and respect their wishes from conception through to completion,” McGrath says. “The team remained sensitive to local political issues and cultural beliefs and it was a tremendously rewarding experience to work closely with the community to deliver the system.”

McGrath’s RAPS wins on another critical front. “The payback period for the system’s implementation is less than eight years in comparison to existing diesel generators, a relatively short turnaround and a significant cost-saving. In fact, the cost of energy from the hydro system is almost half that of the existing diesel systems,” he says.

Next year, Cundall and the School of Photovoltaic and Renewable Energy Engineering will expand the hydro system and develop an interactive community energy grid, including the new hydro system and the existing diesel generators – all of which builds resilience and fosters independence and sustainability into this vulnerable but resourceful Pacific neighbour of ours.

The Fifth Estate – sustainable property news