Is renewable energy ready to disrupt fossil fuels?

Indian workers install solar panels at the Gujarat solar park in Western India's Gujarat state.
Sam Panthaky | AFP | Getty Images
Indian workers install solar panels at the Gujarat solar park in Western India's Gujarat state.

Prices of fossil fuels may be plumbing multi-year lows, but that's not likely to keep them from being displaced by the advance of renewable energy, especially solar, analysts said.

"Renewable energy technologies are far further advanced than many may believe: solar photovoltaic (PV) and on-shore wind have a track record of successful deployment, and costs have fallen dramatically in the past few years," Alex Thursby, chief executive of the National Bank of Abu Dhabi (NBAD), said in a report published this month. "In many parts of the world, indeed, they are now competitive with hydrocarbon energy sources."

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Over the past few years, more than 50 percent of new investment in electricity generation capacity has been from renewable sources, with around $260 billion a year invested in renewable-energy technology over the past five years, said the report, which was prepared for NBAD by the University of Cambridge and PwC.

The cost of solar PV is down more than 80 percent since 2008 and modern wind turbines produce around 15 times more electricity than in the 1990s, it said.

Rising electricity prices

Others also expect the renewable take-up to continue, with low prices for fossil fuels unlikely to derail the momentum.

One reason is that electricity prices will likely continue rising, extending its long-term trend even as oil prices have been volatile, Deutsche Bank said in a late-February note.

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"Over 40 percent of the average electric bill in the U.S. can be attributed to transmission and distribution costs," it said, with most markets allowing utilities to recoup those costs, no matter how the feedstock is priced. Indeed, average monthly prices for natural gas -- a common feedstock for electricity -- declined around 86 percent over the past ten years, but average electricity prices rose around 20 percent over that time, the bank noted.

Low prices for another feedstock -- coal -- certainly haven't derailed renewable take-up. Prices for coal have fallen so much that around 17 percent of U.S. production this year could face idling or closure as mines are unable to cover operating and capital costs, Wood Mackenzie analysts said in a note Monday.

Grid parity

In China, around 70 percent of electricity generation is via coal, but solar targets there are likely to continue increasing as the country faces its pollution problems, Deutsche Bank noted. The mainland's coal use actually declined around 3 percent last year, with officials aiming to further reduce consumption.

Indeed, low fossil fuel prices haven't kept around 50 percent of 60 countries under review from likely already reaching "grid parity" or better on the cost of solar generation, Deutsche Bank said.

It estimates unsubsidized costs for rooftop solar electricity at around $0.08-$0.13 per kilowatt hour, or around 30-40 percent below the retail in many markets globally. In places dependent on coal to generate electricity, the ratio of the costs of coal-based electricity to solar has fallen to less than two to one from seven to one four years ago and could hit parity within 18 months, the bank said. It expects solar-system costs will fall another 40 percent over the next 4-5 years.

The development of cost efficient electricity-storage technology may be the missing link on wider adoption, Deutsche Bank said.

"Solar plus storage is the next killer app that could significantly accelerate global solar penetration," it said, adding it expects "significant progress" on improving the cost within five years.

—By CNBC.Com's Leslie Shaffer; Follow her on Twitter @LeslieShaffer1