Lighting up Tanna Island: Honours research unlocks hydropower potential in Vanuatu

UNSW Engineering Honours student Catherine Le was the recipient of the Humanitarian Engineering Honours Research Thesis Award in 2025 for her comprehensive work on exploring the feasibility of small hydropower plants in Vanuatu.

Inspired by Dr Richard Corkish’s long-standing humanitarian work on Vanuatu’s Tanna island, Catherine focused on the same location for her honours thesis. The third most populous island in Vanuatu, Tanna Island is best known for its active volcano, Mount Yasur. It is also home to many beautiful, secluded waterfalls with the potential to serve not just as popular tourism attractions but sources of renewable energy.

“Vanuatu is the most vulnerable country in the world to natural disasters, and Tanna Island has a lack of reliable electricity due to frequent power outages and extreme weather events,” says Catherine.

“With the electrical grid largely restricted to the main town, many rural communities lack access to reliable electricity. It is important for all of Vanuatu to have a secure energy supply that is cheap, reliable and clean.”

Catherine drew on her expertise in renewable energy engineering to explore the feasibility of small hydropower plants powered by Tanna Island’s dramatic waterfalls. She visited two hidden waterfalls on the island and assessed whether there was sufficient water and natural elevation to build a run of river hydropower plants.

“I then determined the potential power of these sites and put together a financial assessment to establish whether the systems would break even or be profitable,” said Catherine.

Reliable electricity could be life-changing for many residents on Tanna Island, especially through the impact it would have on education and healthcare. For schools, sufficient lighting would allow teachers and students to continue education until nightfall. And for medical aid posts, sufficient lighting and medication refrigerators would greatly improve the quality of healthcare.

The possible impacts also extend into livelihoods and the wellbeing of households. Simple electric appliances could cut down hours of cooking and cleaning time, and freezers could help to safely store food for much longer periods. Workers could benefit from the use of power tools and the ability to work beyond nightfall if needed.

As part of her research, Catherine also assessed any potential environmental impacts of the small hydropower plants. She carefully considered the quantity of water that could be harvested from the waterfalls while keeping the natural ecosystems intact and ensuring that the residents would retain enough drinking water. Land clearing and noise pollution were also considered, however Catherine determined those impacts were minor relative to the enormous benefits clean energy could provide to the island.

Visiting the waterfalls to do an in-person assessment of the accessibility of both sites turned out to be critical.

“It took an entire day to get to each waterfall with hundreds of metres of elevation,” said Catherine. “This helped me to consider how materials would be transported, as access to the waterfalls was extremely difficult.”

Ultimately, Catherine concluded that both waterfalls were profitable and would be extremely useful as self-sustaining renewable energy assets that could generate abundant energy and greatly improve the quality of education and healthcare.  

During her research, Catherine learnt a lot about Vanuatu’s fight for climate justice.

“I discovered that Vanuatu is one of the most vocal Pacific Island countries in international climate change negotiations, with continual calls for higher levels of climate finance from developed countries as a payment for the impact of their carbon emissions,” said Catherine.

“Increased access to clean energy can foster a newfound sense of self-reliance and autonomy among the rural population, which may push leaders to act on their promise of a 100% renewable energy future in Vanuatu by 2030.”

Catherine says that her thesis journey enabled her to expand her technical knowledge while contributing to something impactful.

“Although I studied renewable energy engineering, hydropower was still a fairly untouched subject for me. It was really exciting and refreshing to work on a technology that I was less experienced with,” said Catherine.

“What I didn’t expect was how rewarding it felt to contribute to such a meaningful project so much bigger than me.”

“The most impactful thing I learnt throughout my thesis journey was how supportive and collaborative the whole process was. I truly couldn’t have completed my work without the locals’ guidance and knowledge, Dr Richard Corkish’s guidance, and my fellow students’ support on the trip through helping me take measurements and encouraging me the whole way.”

Catherine has recently started a role as an Analyst for Aurora Energy Research, where she is enjoying applying and expanding her knowledge further.

“I am super excited to continue my journey in the renewable energy sector and contribute meaningfully to a clean energy future,” said Catherine.

“In this role I am being introduced to the bigger picture of the energy market and how predicting the market can empower developers to make decisions towards a better future.”