WASHINGTON - Solar energy dominated global investment in new power generation like never before in 2017, a new study says.
The world installed a record 98 gigawatts of new solar capacity, far more than the net additions of any other energy technology - renewable, fossil fuel or nuclear - says the "Global Trends in Renewable Energy Investment 2018" report released on Thursday (April 5).
One gigawatt of power is roughly enough to light up 100 million LED bulbs. It takes almost 6.7 million solar panels to generate one gigawatt.
The report by Bloomberg New Energy Finance (BNEF), the United Nations Environment Programme (UNEP), and the Frankfurt School-UNEP Collaborating Centre, points to a fundamental shift, but also warns that huge challenges remain in switching from fossil fuels to clean energy.
Its lead author, BNEF chief editor, Mr Angus McCrone, told The Straits Times: "There's been a realisation in the last year or so that if you're looking to build cheap generation assets - cheap in terms of cost of generation - in many places in the world, not only solar but wind may be the cheapest technology."
"You couldn't have said that five or 10 years ago. That is a big change," he said.
The current level of electricity generated by renewables including solar power corresponds to about 1.8 gigatonnes of carbon dioxide (CO2) emissions avoided - roughly equivalent to those produced by the entire US transport system, the report said.
But renewable energy still accounts for only a small part of the energy mix.
"We are only inching upwards in the share of electricity that is generated from renewable energy sources, it is still only 20 per cent of overall electricity," Mr Marcel Alers, head of energy at the UN Development Programme's Global Environmental Finance Unit, told The Straits Times over the phone from New York.
For instance, the world still consumes more than 90 million barrels of crude oil per day. In 2016, transporting crude oil alone produced 7.5 gigatonnes of the CO2 emissions that are drivers of global warming.
Still, the economic case for building new coal and gas capacity is eroding, analysts say.
Last year, solar power attracted US$160.8 billion of investment globally, more than any other energy technology, the report says. Investment in solar energy accounted for 57 per cent of last year's total investment for all renewable energy - excluding large hydro projects. It outstripped new investment in coal and gas generation capacity, estimated at US$103 billion.
China was responsible for much of the growth in solar power, the report says. An "unprecedented boom" in China last year saw some 53 gigawatts added - more than half the global total - and US$86.5 billion invested, up by 58 per cent. There were also sharp increases in investment in Australia, Mexico and Sweden.
Some big markets showed declines.
In the US, investment in solar power dropped 6 per cent to US$40.5 billion. In Europe, there was a fall of 36 per cent, to US$40.9 billion, with big drops in the United Kingdom and Germany. In Japan, investment slipped 28 per cent to US$13.4 billion. The fall in investment generally reflected a mix of changes in policy support - such as discontinuation of subsidies and the timing of large project financing.
The report emerged just a week after Saudi Arabia announced on March 27 in New York, an ambitious solar project in the desert backed by Japan's Softbank Group, which if completed - in around 11 years - will be the biggest in the world by far, generating as much as 200 gigawatts.
Solar energy could meet as much as a quarter of Singapore's energy demands by 2025, according to a white paper last year by the Sustainable Energy Association of Singapore, a non-profit business association.
In terms of slowing global warming, however, there is still a mountain to climb.
Said Mr Alers: "It is definitely positive that renewables are coming on strongly, fuelled by lower costs and growing demand. Within renewable technologies, solar is progressing very fast, and wind may even have larger potential," he said.
"But after several years in which global emissions seemed to level off, they have started picking up again. This is not good," he warned.
Referring to a target in the Paris Climate agreement, he said: "To keep temperature increase to within two degrees, global emissions of CO2 need to peak latest by 2020 and then start to gradually decrease. Every year of delay in that peak is a problem."