SINGAPORE - People have long dreamt of harvesting energy directly from the sun.
That dream became a reality when Bell Laboratories unveiled the first modern solar cell made of silicon 60 years ago.
And in Singapore, solar cells have been around for more than three decades, warming water for homes and generating electricity for bus shelters and a Pasir Ris fish farm.
In fact, the earliest research started long before a recent national push turned solar energy from a minor curiosity in Singapore into a part of a $1.7 billion clean-energy industry.
In 1839, French physicist Alexandre Edmond Becquerel first noticed small electric currents being produced when metals in an electrolyte solution were exposed to light.
More than a century later, researchers from Bell Labs, the renowned research arm of telecommunications firm AT&T in New Jersey, noticed the same effect with a silicon material.
The first modern solar cells were made of silicon doped with arsenic and boron, and were able to convert about 6 per cent of the light that hit them into electricity.
Today, solar photovoltaic or PV cells are typically made of a silicon semiconductor material containing deliberately introduced impurities to alter its electronic properties. The material absorbs some of the light that hits it, and electrons within the silicon cell are knocked loose and able to flow freely. The flow of these electrons is a current.
Initially, Bell Labs' solar cells were used to power telecommunications equipment in remote areas. By 1958, they had gone to space on the Vanguard satellites in the United States' space programme.
At first, the cost of solar cells was astronomical, at up to US$250 per watt of generation capacity in the 1950s, compared to about S$1 a watt today.
Even so, the 1979 energy crisis caused by the Iranian Revolution sparked renewed interest in solar energy around the world, including Singapore.
Many in landed homes chose to install solar water heaters, which do not generate electricity but simply heat water collected in a tank.
And in 1983, a floating fish farm off Pasir Ris, Marina Farm, installed a $6,000 set of solar panels to cut its $800 diesel generation bill by half, while the Port of Singapore Authority started using solar cells to power its navigational beacons.
Despite foreign investments in electronics manufacturing then, there were only a handful of solar-system manufacturers and installers here in the 1980s.
Among them were Sunergy Manufacturing, Solar Generators Singapore and Compo Enterprises, the precursor to solar firm Sunseap.
"Local demand was so small, so what we did was mainly for re-exporting," said Compo and Sunseap founder Phuan Pui Jong, 70.
Research, too, was paltry, said Professor Yoon Soon Fatt, chair of Nanyang Technological University's school of electrical and electronic engineering.
"We did some work in the early days on the structure of silicon solar cells," said Prof Yoon, who joined the then-Nanyang Technological Institute in 1989.
"At that time there was no support, nothing. But as a young faculty member, you're always looking for new research areas. Solar PV was something that was interesting; the dream was to try and see how to squeeze as much efficiency out of silicon as we could."
It ramped up slowly. In 1982, the National University of Singapore built a $10,000 prototype low-energy house at its Kent Ridge campus with solar panels on its roof, while Singapore Polytechnic and Ngee Ann Polytechnic installed their first solar panels between 1991 and 1996 to test how well various systems worked in a humid tropical climate.
And the first solar installation to be connected to the national grid was a 4.2-kilowatt set-up at Tuas Naval Base in 1997.
In 2007, national support for the industry took a sharp turn.
The Economic Development Board injected $350 million into growing the clean energy sector, from research to test-bedding new technologies - both to boost energy security here and to diversify industry.
In 2011, these were topped up with an infusion of $195 million, while a National Innovation Challenge for new research on energy resilience received $300 million.
"Finally somebody was willing to fund this sort of research'," Prof Yoon said. "It's nice to look back and think we've come quite far over the years."
In 2010, the Housing Board began installing solar panels en masse on HDB rooftops to power lights and common areas, in a five-year, $31 million drive.
Today, the total installed solar capacity here is around 15 to 20 megawatts, a tiny fraction of Singapore's energy needs.
But a White Paper last year by the Sustainable Energy Association of Singapore suggested solar PV could meet some 4.8 per cent of the country's 2025 energy needs, especially as costs go down, and if steps are taken to manage the intermittent nature of the sun's energy.
"The future of solar will be several gigawatts of solar installed in Singapore," said Solar Energy Research Institute of Singapore chief executive Armin Aberle.
This article was published on May 4 in The Straits Times.
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