Powering the grid

Tuesday October 15, 2019 Written by Published in Environment
June Hosking's daughter-in-law Erica with recycled wax candles. 19101141 June Hosking's daughter-in-law Erica with recycled wax candles. 19101141

With solar power’s shortcomings, the Cooks need more renewable energy options. This week a visiting expert discussed solutions like hydro and wind-power. 

On Mauke, when they installed solar power last year, everyone was excited.  People bought extra freezers to run; they thought it would mean they wouldn’t have to pay for power, or it would at least be cheaper. 

The solar plant officially opened this year.

But resident June Hosking says they’re still paying for power on Mauke, and and sometimes have to resort to using diesel-run generators, which can be polluting and noisy and not always very efficient.

“The government is aware that the solar batteries only have a 10-year life,” says Hosking.

The project for Mauke’s solar grid mounted to millions of dollars to start up, but the government also needs to allocate a budget for battery replacement and disposal.  “We are not there yet,” says Hosking.

There are no magic answers to renewable energy; just as there’s no such thing as a free lunch, there’s no such thing as free power. So what is the Cook Islands doing to progress towards its vision as a Pacific Island fully-powered through renewable energy sources?

Up until 2010 fossil fuels like diesel were the sole source of energy for electricity on the islands, and then the Government announced its renewable energy vision.

Te Aponga Uira chief executive officer Apii Timoti says they embarked on a number of studies that involved assessing the renewable energy potential of the country followed by a number of engineering and economic studies to understand their impact.

A number of strategies were developed including direct connection of solar generators to the power grid, installation of batteries as short term storage to promote energy efficiency and to boost the power grid.

“Solar is the main energy source for us mainly because of the ease of accessing it. Other potential energy sources were investigated and this included wind, waste, tidal and hydro. I think eventually a combination of all of these will be our renewable energy future.”

Timoti says there will be plenty of benefits, the obvious one being our energy independence.

“We will no longer be subjected to the global fluctuations in the costs of diesel,” says Timoti. “There is of course the climate impact, reduction in diesel usage means reduction in CO2 emissions. There is also a new industry, renewable energy, that is emerging. Some people are earning money from their solar systems.”

Most of the outer islands run completely on solar power now but it isn’t as glamourous as it seems.

 

June Hosking knew from her experience with living off the grid that the balancing of power usage on Mauke’s solar panels would have to be done carefully.

“From too many people putting the jug on in the morning to no one using enough power at night to cycle the charge, so much could go wrong,” says Hosking.

When the solar power system was first introduced, it didn’t include Hosking’s house which is on the south side, a fair distance from the township and residential area.

Hosking already had her own solar panels and batteries but it wasn’t exactly easy to manage.

She had a freezer running in her home that would drain the batteries too low and they would take longer to charge and they would have to use a generator to top the batteries up.

So Hosking stopped using the freezer and decided to dry meat and preserve food in bottles and jars. But then she had another problem: she wasn’t using enough battery power and the batteries couldn’t cycle, which meant their life was shortened.

Hosking and her husband live without lights on at night but during the day they are able to charge some LED lights. They are able to charge their phones and run the washing machine and the water pump too.

It’s been a trial and error process for Hosking, and stormy overcast days don’t help either.

This week, Te Aponga Uira invited Geoff Stapleton to conduct training in Managing Renewable Energy Solar systems held at the USP Campus.

 

Stapleton is managing director of Global Sustainable Energy Solutions in Australia, and brought with him experience in designing, installing, and managing solar energy systems.

The purpose of the training was to strengthen the capacity of the electrical industry in managing solar energy systems with considerations given to battery storage solutions that may apply to future home and business connections.

Due to the Cook Islands developed country status we miss out on the Sustainable Energy Industry Development Project which has funding is from the World Bank and the Pacific Power Association in Suva but Te Aponga Uira is still contracting GSES to conduct the same workshops being conducted in the other countries.

Stapleton said good quality solar modules have a life expectancy greater than 30 years however the batteries will not last 30 years and the replacement cost should be included within the tariff being charged for the electricity.

Stapleton added “It would be good if the country had mini-hydro or micro-hydro but I do not think they have many options on Rarotonga. Wind is also a possibility but it is important that if they are installed they are designed to withstand cyclones.”

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