Bernstein's mid-November report stressed a strongly positive outlook for renewables in Asia.
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"Renewable energy is a technology. In the technology sector, costs always go down. Fossil fuels are extracted. In extractive industries, costs (almost) always go up," it said. "Renewable and fossil fuel cost per unit of energy are now roughly comparable in many places… but heading in opposite directions," the report said. "New, superior technologies don't split markets with old, inferior technologies."
The oil technology -- fossil fuel -- has certainly seen a precipitous price decline recently. Brent crude prices have tumbled 35 percent over the last six months driven by an oversupply from the North Sea and Atlantic Basin amid increased production in North America.
But others also noted that renewable energy use may not suffer much.
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"Crude oil price weakness unlikely to exert pressure on wind and solar, as oil is not a substitute," UOB KayHian said in a Thursday note on China's renewable energy sector. "It is very rare for a country to use crude oil as a major source of power generation," it said, noting that within China, at least, renewables are almost solely used for power generation.
Indeed, in China, Europe and the U.S., natural gas provides more competition for renewable energy than oil, noted Xizhou Zhou, senior director at IHS Energy. In these regions, natural gas is generally traded independently of oil, with its link to crude prices weakening, he noted.
"In the short term, utilities might want gas more than renewables," he said, but he doesn't expect the lower fossil fuel prices to affect renewable demand much in the short-to-medium-term. IHS expects oil prices could remain low for the next couple years, and it's only likely to affect renewable demand if they remain relatively low for longer than that, he said.
That's partly because renewable energy generally receives subsidies from governments, a practice likely to continue, Zhou said. Coal, which is in wide use for power generation in China, has always been cheaper than renewables, but the 40-60 percent decline in coal prices over the past few years hasn't dented growth in China's renewable energy business, he noted.
Climate change factor
Price isn't the only driver behind the pickup in renewable energy use, UOB KayHian noted, citing climate change concerns.