Tonga BESS – Grid Stability & Load Shifting on Tongatapu
Throughout 2021, Infratec supported head contractor Akuo Energy SAS Ltd to install two large battery energy storage projects in Nuku’alofa, the capital of Tonga – at the time, the largest battery energy storage system in the South Pacific.
Traditionally reliant on expensive and polluting diesel imports for electricity, the Kingdom of Tonga is in the midst of a renewable energy revolution, transforming the country’s electricity system from one that was 11% powered by renewables as recently as 2018, to 50% by 2025 and ultimately 100% by 2035.
It’s hard to overstate the importance of these assets in providing the backbone for a renewable-powered grid. The batteries serve distinct and critical functions for the Tongatapu grid:
- #1 – A 7.2MW/3.8MWh battery provides frequency support to the power grid (typically provided by diesel generators).
- #2 – A 6MW/20.9MWh battery stores energy generated during the day from a newly built solar farm, to be released during the evening peak load.
Infratec deployed a skeleton crew of New Zealand specialists coupled with the capable support of our local partner, JH Electrical. Infratec safely installed over 160 tonnes of battery modules and successfully managed several planned outages, including switching off the entire electricity supply to Tonga’s capital, Nuku’alofa, for a period of 8 hours while additional switchboards were installed.
The experience proved that it is still possible to deliver complex projects during a pandemic when you have good local partnerships in place.
