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Fighting for solar power in a concrete jungle

From rooftops to reservoirs, Singapore is doing everything it can to maximize its unique living space for renewable energy.

Public Utilities Board, Singapore

This is part of "Fight The Power," a series about the people, organizations and countries transforming the way we think about energy for the better.  

Hot, humid, sunny and home to a population of 5.7 million, Singapore may seem like the ideal spot for solar power generation, but that's not the case.

With a mere 278 square miles of urbanized land and filled to the brim with skyscrapers and apartments, Singapore lacks the space for solar farms found in much larger countries. Instead, Singapore still heavily relies on fossil fuels such as oil and natural gas to generate the 48.6 terawatt-hours (TWh) of electricity it consumed in 2017.

Much of that serves to keep its residents cool: Air-conditioning amounts for 36 percent of electrical use in homes.

While solar may seem like a wistful dream in the land-scarce island, Singapore's Energy Market Authority has set a target to generate 1 gigawatt peak (GWp) beyond 2020, which it says will be sufficient to power 200,000 four-room flats annually.

Here's how it will all go down.

Of rooftops and reservoirs

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Solar panels adorn the roofs of HDB flats in the suburb of Jurong, Singapore.

Sunseap

With a population density that ranks third in the world -- ahead of Hong Kong even -- Singapore relies on affordable and uniform-looking public housing to cater to its masses. Unlike the unique skyscrapers in the central business districts, these buildings sport flat rooftops, ideal for installation of solar panels.

In 2010, the housing board implemented a five-year S$31 million (about US$23 million, £17 million or AU$30 million converted) drive for panel installation, which has since seen over 1,898 installations islandwide. It may not seem like much, but these installations generate about 143 megawatt peak (MWp) of electricity, enough for around 28,600 homes.

These installations aren't done by the government. Instead it's solar startups, such as Sunseap, that fork out the cash to lease out space on rooftops and install their panels. Currently the startup generates about 100 MW daily that it pumps back into the energy grid. With panels expecting to last for 25 to 30 years, the company is in for the long haul, and generates revenue by selling energy credits to eco-conscious companies, such as Apple and Microsoft.

Globally, Apple is already 100 percent powered by renewable energy in the 43 countries where it has facilities. In Singapore, it draws on Sunseap's supply as well as power from its own building, which it claims is one of the largest solar installations in the island state, to power both its offices and its Apple Store.

In Microsoft's case, the company is committing to purchase about 60 MWp of power from Sunseap for the next 20 years. Announced earlier this year, the energy agreement marks Microsoft's first renewable energy deal in Asia and will be used to power its data centers locally.

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Floating solar platforms at one of Singapore's reservoirs.

Public Utilities Board, Singapore

With land space a premium in Singapore, the government is looking to take advantage of its 17 sizable water reservoirs as an alternative location for solar panels. The Public Utilities Board (PUB) is currently trialing floating solar platforms, and results so far have been promising, with systems performing 5 percent to 15 percent better than a typical rooftop system due to the cooler temperatures of the reservoir environment.

"While most solar PV panels are deployed on land or rooftops, the reservoirs with open surface areas present great potential for harnessing solar energy, especially in land-scarce Singapore," said a spokesperson from PUB.

The spokesperson also added that the agency was looking into using renewable energy generated by the solar platforms for its facilities but was unable to comment on how much electricity would be generated until further studies are done.

If the trials are successful, it's not unlikely that more such platforms will be deployed, eventually possibly blanketing the reservoirs with panels. While it might seem like a bad idea to introduce foreign material to a water supply, PUB claims that tests so far show no contamination of the water.

Not the ideal weather

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A particularly cloudy and rainy day means there's barely any electricity generated.

Energy Market Authority, Singapore

Even as the country finds space for its solar ambitions, Singapore also has to figure out how to tackle a problem stemming from its location near the equator -- cloud cover and tropical storms. Contrary to popular belief, despite having around 12 hours of sunlight a day, Singapore's effective solar irradiance is only about 3.5 hours daily.

The Energy Market Authority recently awarded US$4.6 million grant for solar forecasting, a process of understanding the sun's movement and how much power is being generated to the grid, which will allow fossil fuel energy producers to regulate output and cut down on production when electricity from solar panels flood the grid.

"Forecasting solar power output in Singapore, especially over long time horizons, is challenging due to the complexities of our local weather conditions," said an EMA spokesperson.

"The ability to forecast solar photovoltaic power output accurately will allow us to take appropriate and timely actions to balance the grid."

Everyone can solar

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Rooftop solar panels on an apartment complex.

Aloysius Low/CNET

Besides backing rooftop and floating platforms, the EMA is making it easier for companies and consumers to invest in solar -- companies will find it easier to sell excess power back to the grid, and consumers will find less red tape to deal with when registering to install their own solar panels.

Other new business models will also allow for solar leasing, through which consumers can lease panels and pay for electricity at agreed rates, without having to invest in installing and buying their own.

While it's unlikely solar will ever fully power Singapore's electrical needs, there appears to be a big push toward tapping a natural renewable resource that could provide a significant chunk of the country's power requirements.

Perhaps in the future, when scientists figure out how to improve on the current solar efficiency, Singapore will finally figure out how to use the power of the sun to keep the entire country cool. 

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