Block diagram of a Solar Power Plant


  Barbie - Miss Tokelau 2019

I was reading "Clean Disruption of Energy and Transportation" by Tony Seba when I came across a reference to Tauranga. My interest was aroused because I lived in Tauranga for about 14 years (1972 - 1986).

Tony Seba: "PowerSmart Solar, a company based in Tauranga, New Zealand, built Tokelau’s solar installations. Dean Parchomchuck, a co-founder of the company, led the installation team on the islands. I met him over coffee at the University of Auckland Business School, where he told me that his company’s solar installation took a grand total of 22 weeks."

"The first atoll took ten weeks and the second and third atolls took about six weeks each. Here you can see the solar installation learning curve at work. Had there been a fourth atoll, the installation time there would have been even shorter. The three solar power installations consist of 1.5 MW of solar photovoltaic panels and on-site battery banks that store the energy for night time and rainy day usage."

PowerSmart started work on the project in June 2012 in collaboration with energy consultancy IT Power Australia.

Three hybrid power systems were installed to supply 90+% renewable electricity to the three atolls: Nukunonu, Fakaofo and Atafu with a total population of 1,500 people.

These systems consisted of between 240 – 400kW of PV and 1.4 – 1.9 MWh of lead acid battery banks.

The solar power systems include a total of 4,032 PV panels, 392 inverters and 1,344 batteries.

A variant on the above generic block diagram, as found in Tokelau, is that some PV arrays are not connected to the battery bank via a solar charge controller. Instead, the solar PV 48V DC output is inverted and passed directly into the nominal 230V 50 Hz AC network and transformed to 11kV for transmission to the villages.

On Oct 30, 2012 PowerSmart announced it had completed the the NZD-7.5-million (USD 6.2m/EUR 4.8m) project, financed by New Zealand.

 From Tony Seba:

"The World’s First Solar Nation of Tokelau became the first nation in the world to go 100-percent solar. Tokelau is a decidedly small nation with a population of 1,411 people spread over 12 square km on three atolls. Tokelau switched to solar because the nation had a problem that is typical of diesel-powered economies."

"Tokelau used to spend about NZ$ 1 million (US$ 0.83 million) on diesel fuel per year. This doesn’t sound like much until you consider the island nation’s total GDP, US$1.5 million. Fifty-five percent of the island’s income was spent for diesel fuel to power its economy. This all changed when the island went solar. Much of the conversation about electricity focuses on the levelized cost of energy. Few people take into account the quality of life that dependence on the fossil fuel drug engenders. Diesel is so expensive, diesel generators in Tokelau were shut off at night to save money".

"Medicines that needed to stay cool round-the-clock would go bad; patients who needed treatment at night would go untreated. Diesel was delivered by boat once a month. Sometimes the islands ran out of diesel altogether and would have to wait for the next shipment in the dark. Diesel was at best an intermittent source of energy. Now that they are off diesel, Tokelauans will nearly double their income, raise their quality of life, and have a 24/7 supply of energy."

Ref: Seba, Tony. "Clean Disruption of Energy and Transportation: How Silicon Valley Will Make Oil, Nuclear, Natural Gas, Coal, Electric Utilities and Conventional Cars Obsolete by 2030" Kindle Edition, 291 pages Published June 16th 2014

Location of Tokelau Atolls
Atafu map - Tokelau Islands

Ref: IT Power Group, "Tokelau renewable energy project review" Ministry of Foreign Affairs and Trade (New Zealand) 15 DEC 2013

Ref: Empower Consultants, "Hybrid Photovoltaic/Coconut based Power Systems in Tokelau - Consultancy for the Feasibility, Environmental Impact Assessment, System Design and Specifications of Major Components and Financing Strategy Report on Feasibility, Environmental Impact Assessment, Overall System Design and Specifications and Financing Strategy," Final Version – March 2008

Solar Power Plant - Nukunonu Village - Tokelau
Goods transported by barge from cargo ship to Nukunonu Village
Backup motor-generator set at Nukunonu Atoll


10 - 15kW wind generator installed in 2019 in Tokelau

The 2008 feasibility study conducted by Empower Consultants, based in Wellington, New Zealand, found that each atoll will need 20 to 30 litres of coconut oil per day – around 200 coconuts if 90% of of the electricity each day is provided by the solar system and 10% by coconut oil - being a direct substitute for diesel.

In practice it appears that diesel oil continued to be used in Tokelau for back up power production.

From an interview on Dateline Pacific, 3:03 pm on 29 June 2017:  
  DOMINIC GODFREY (Broadcaster at Radio New Zealand): So currently, how much of the nation's power is being generated sustainably?  
  ROBIN PENE (Tokelau's Director of Energy): Well at the moment, if we get six to seven hours of bright sunlight a day, we don't need anything else. It's all produced by solar PV which supplies the village during the day and the extra power we use to charge a number of battery banks we have on island. And as the sun goes down and the radiation reduces, the batteries slowly take over so that the village runs entirely on battery power during the night, until the morning when it repeats itself yeah.  
  DG: So what happens when there isn't the six to seven hours of sunshine?  
  RP: Yes unfortunately we do get cloud cover, and of course the radiation factor reduces quite a bit, and in that case at the moment we have to start up the diesel and burn more diesel. On our annual basis there, at present we're about 80 percent renewable energy efficient. In 2013 after solar was established we had our best record and that was 92 percent renewable energy. When you consider that the system was only designed for 80 percent, so we did quite well that year. We seem to be getting more and more wet weather, probably due to the changing weather patterns, so we find ourselves having to use the generators considerably more than what we previously had.  
  DG: So hence the introduction of wind turbines?  
  RP: Yes so we're looking at alternatives. The Tokelau energy policy is that we're trying to become 100 percent so we're looking at ways how to manage that and the first one is the obvious wind turbine. The wind turbine technology these days has improved considerably in the last ten years. We have a low wind factor overall in Tokelau because of our situation in the world but it's sufficient for this particular type of wind turbine.  
  I've gathered quite a bit of information from the weather stations we have on Atafu and Fakaofo and the results indicate that it is a possibility - well I've been told that it will work - so what I'm doing now is trialing a ten kilowatt wind turbine which will be the generation we'll use. We'll trial that for four to six months and if it proves effective, proves the data correct, then we'll implement probably three to four on each atoll. And that I see as bringing us up to 98 percent, to be conservative, renewable energy efficient.

Laptop Control
Construction goods on a barge at Nukunonu Atoll
Installing Solar Panls - Tokelau
Sonny Island Chargers and Sonny Boy String Inverters in a Tokelau Solar Power Plant.
48V lead acid batteries in a Tokelau battery room
Control Panel for a Solar Poer Plant in Tokelau

SMA Solar Technology AG (SMA) delivered 93 Sunny Island inverters to control the standalone systems on the three coral islands and 205 Sunny Boy inverters to convert the direct current produced by the photovoltaic panels into the alternating current necessary for electrical appliances. At the time of installation - 2012 - SMA stated that the 1 MW system was the largest standalone solar power system in the world.

Control and indication cables are run to the power station equipment so that the plant can be both locally controlled by computer or remotely by technicians based in New Zealand over a satellite link.

A remote link assists in:
• Reducing costs associated with remote site visits.
• Receiving quick notification and act to eliminate power interruptions at a site.
• Facilitating troubleshooting
• Programing custom settings off-site
• Updating firmware remotely

Satellite Communications - Tokelau
Erosion under a sea wall in Tokelau
Kiribati - waves - house



There are many reports related to actions being taken to mitigate the effects of climate change available from

No significant land on Tokelau is more than two metres above high water of ordinary tides. Storm surges associated with tropical cyclones and spring tides can sometimes inundate villages. In February 2005 Tropical Cyclone Percy, a category 5 storm, had a severe impact on Tokelau with storm surge inundating all three atolls.

"The high surge allowed the powerful winds to send waves sweeping across the low lying atoll islands. Waves swept over from both the ocean and lagoon sides of the atolls, clashing in the middle of the islands and swamping villages" reported the UN Office for the Coordination of Humanitarian Affairs

Coastal management is also being undertaken to adapt to climate change and rising seas. In 2014 the Atoll of Atafu planned to get swamp mangroves introduced from Fiji to help prevent erosion, provide protection from storm surges and provide coastal habitats for fish nurseries.

Pigs in Fakaofo appear to have adapted, and now forage at low tide for seaweed, crabs, mussels, fish and eels marooned in rock pools.

Pigs foraging at low tide in Fakaofo atoll.
Pig paddle
Looking for Tokelau at the end of the 21st Century