Beyond Tokelau’s 100% solar: add wind power!

Tokelau was the first nation in the world to go 100% solar in 2012. Now the country is aiming to keep its fully renewable energy status in the future using wind power. This is going to reduce the need for diesel fuel backup in prolonged times of cloudy weather, and when the solar cell system needs maintenance.

Robin Pene, Director of Energy in the Tokelau government, says there has been a reduction in efficiency of the Tokelau solar system as time went on. This is partly a result of system overload due to high demand. In fact consumer demand had risen 25% by 2014. That means the power system has been operating at the high end of its capacity, which potentially reduces its life span to less than the designed 10 years.

Hence the need for system expansion: capacity is now being increased by the installation of additional solar panels, but thinking is going beyond that.
The proposed wind turbine situated near the community restaurant Te Papa in Fakaofo.
Hardly ever short of wind, the proposal is for each atoll to have three wind generators, with an added average 15 kilowatts (kW) electricity output. They will be used as a backup energy supply at times of cloudy weather and when the sun goes sets, or when the solar system is down for maintenance and through occasional failure.

The original system on each of the three atolls Fakaofo, Nukunonu and Atafu was designed to generate 45kW each, but demand has risen to 50-55 kW. Power black-outs resulted when demand rose to 90 kW in extreme situations. This was the case during the 150-years Catholic church celebrations in Nukunonu in 2015, when the local population of about 450 souls doubled for a week.

Reliable power supply is an important aspect of Quality of Life, Robin Pene says, which is what the atoll-dwellers are entitled to. And so capacity will be increased by 33 kW on each atoll. “We can make some power savings by using better quality power cables, by replacing light bulbs and installing LED lights, and even with the choice of foods,” he says.

One of the reasons power demand has gone up is that people are now more likely to use electric frying pans for food preparation. And so people now eat more fatty foods – already a problem in the islands. Much better to use barbeque instead, he says: it saves power, and the fat drips off before you eat the food prepared on it!

Wind turbines will help keep the energy production sustainable, Robin says. Already on order, the first Osiris generator one will be trialled in Fakaofo, immediately next to the old hospital site TePapa. This was recently transformed in a community restaurant by the Aumaga, the working men’s group, for use by the Fatupaepae, the local women’s group.
Installation of additional solar panels on the roof of the Nukunonu power house, that contains the banks of batteries being charged.
Eventually each of the three Tokelauan atolls will have a hybrid system, comprising an extended solar panel system with a wind generator backup. Some diesel for power generation will still be required at times to fully boost the batteries occasionally, to extend their life span. But overall this will be the exception rather than the rule. And after that?

“We’re already looking at the production of biogas from piggeries waste and village waste water,” Robin says. “That would provide methane gas for cooking, fertiliser for our keyhole gardens, reduced greenhouse gas emission, and cleaner water returned to the lagoons. The gas can also be used for lighting, or compressed as CNG for fuelling motors and generators. All important steps for sustainable life in Tokelau.”

For more information email Robin Pene, Director of Energy.