Nuclear power is one of the most hotly debated sources of renewable energy. It's costly and potentially disastrous but it can generate electricity without producing any greenhouse gas emissions.
According to a report from the International Energy Agency (IEA), the power sector should more than double the amount of nuclear energy produced in order to keep warming below 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-Industrial Age levels, reaching 930 gigawatts of nuclear-generated power by 2050. That's a 57 percent increase over the current global capacity, which would boost nuclear's share of the world's energy production from 11 percent to 17 percent.
"Simply speaking, to make the transformation of our energy sector a reality, we will need to use all low-carbon energy sources available to us, including nuclear energy," IEA Executive Director Maria van der Hoeven said in a statement accompanying the report's release.
The report, which outlines a "roadmap" for growing nuclear energy production, is based on a model that finds the most cost-effective mix of energy options for developing a global power sector that can meet the goal of keeping warming under the 2-degree mark. The model assumes that any plants still emitting high levels of greenhouse gases after 2020 will need to have carbon capture and storage technology, and factors those costs into its predictions.
'It looks like a nuclear industry wish list.'
"If we want to really go for a decarbonized power sector, we can't have any plants without carbon capture and storage," Cecilia Tam, a co-author on the report, told VICE News. "They'll need to be retrofitted with such technologies if they're going to continue operating in the future."
Carbon capture and sequestration (CCS) technology aims to remove carbon dioxide from power plants before it is emitted into the atmosphere. The captured carbon is then buried in the ground. CCS has not, however, been deployed on a significant scale and has proven to be prohibitively expensive for energy companies to operate.
The report estimates that nuclear energy currently reduces global carbon dioxide emissions by between 1.4 billion and 2.8 billion tons every year, about the amount emitted by 165 million homes every year.
The IEA's last nuclear roadmap was released in 2010, before a major earthquake and tsunami caused a core meltdown at Japan's Fukushima Daiichi plant in 2011. Since that accident, acceptance of nuclear power has shifted, causing some countries to change their policies. Energy production from nuclear declined 10 percent between 2010 and 2013, largely due to Germany shutting down eight reactors and Japan taking its reactors offline.
"What we've seen in different countries is that people have been scaling back their ambition," Tam told VICE News.
Reaching the 930-gigawatt goal would require an investment of $4.4 trillion between 2011 and 2050, a quarter of which would come from China. Member countries of the Organization for Economic Cooperation and Development would contribute about $2 trillion collectively.
The roadmap calls for countries' investments to increase over the coming decades. The United States, for example, would invest $90 billion in nuclear through 2020, with that amount growing to $118 billion between 2041 and 2050.
"It looks like a nuclear industry wish list," Edwin Lyman, senior scientist at the Union of Concerned Scientists, told VICE News. "I don't think it's a serious analysis of the complexities and difficulties of trying to increase nuclear capability substantially around the world."
Building a nuclear plant can take between five and seven years and run between $3.5 billion and $5.5 billion, according to the IEA report, though costs vary in different regions. The expense and complexity of such projects often means that they're fraught with delays and cost overruns.
Georgia's Plant Vogtle, which was approved for construction in 2012, was expected to cost $14 billion and to start producing power in 2016. But it is now hundreds of millions of dollars in the red and projected to come online in mid-2019, largely due to regulatory delays and improperly constructed foundations.
Two US plants in the past two years have shut down due to lack of financing. In 2013, Kewaunee Power Station in Wisconsin closed after utility companies decided to switch to cheaper natural gas and no buyer could be found for the plant, leaving the operators with a decommissioning process that could cost nearly $1 billion and take six decades to complete. And in December, the Vermont Yankee plant ceased operations after decades of energy production, also due largely to competition from cheap natural gas.
Expanding nuclear capabilities also means an increased risk of using those capabilities for weapons, Lyman said, and the current global structure for monitoring nuclear development is unlikely to be able to support such growth safely without significant changes.
"There's no doubt that if you could increase nuclear power in a safe and secure fashion, then it's one option for reducing greenhouse gas emissions," Lyman told VICE News. "But that's not news. The issue is, can it really be done reliably, economically, and safely?"
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