On September 3, China and the United States signed the Paris Climate Agreement, bringing the reality of its implementation that much closer. When 55 countries that together generate at least 55% of the world’s emissions sign on, the agreement will come into force. Translating the agreement’s commitments from theory to practice, however, will require massive changes to global energy infrastructure.
The deal’s core elements are the Intended Nationally Determined Contributions, voluntary commitments decided upon by each nation that detail how and to what extent they will reduce their greenhouse gas emissions. Most nations plan to address the electricity and heating sector, which now generates 25% of global emissions.
In doing so, many will pursue alternatives to coal and oil for electricity generation, and the nuclear industry has been lobbying world leaders to be chosen as the proven, scalable option. Of course, since the Fukushima disaster, there has been pervasive opposition to the use of nuclear energy for this purpose. Some countries have gone so far as to shut down their nuclear plants altogether. In an era where mitigating climate change is the greatest priority, destroying existing nuclear infrastructure would be reckless. Yet despite its potential, and much to the dismay of the aforementioned lobbyists, nuclear power‘s drawbacks keep it from being more effective than natural gas for replacing coal and oil in generating electricity. Alas, the question remains: where should world leaders turn for lower emitting electricity generators?
Renewables would be the ideal option. Geothermal and hydropower, for instance, are both clean and provide consistent power; wind and solar, meanwhile, are both scalable, and their prices have dropped dramatically in the past decade. Due to various limitations, however, renewables alone cannot satisfy the world’s demand for power. Geothermal plants are limited in where they can be built, and wind and solar are restrained by the intermittency of the sources from which they derive power. Improved battery technology would make it possible to store surplus electricity for cloudy days with little wind, but the technology is not there yet. Batteries are still extremely expensive for end consumers, and there is not yet a business case to be made for electricity providers to invest heavily in storage for renewable power.
Even despite the lack of battery technology, however, the United States and growing economies in the developing world alike can reliably use renewables to meet their Paris commitments if they pair them with a vital energy alternative: natural gas. Though renewals are not always reliable, natural gas power plants are “peaking plants”—those that can have their output dialed up or down in a matter of minutes in order to satisfy demand at peak times of the day. This quality allows natural gas to serve as a flexible backup power supply when the wind and sun ebb or demand spikes.
When compared to nuclear, natural gas also enjoys the advantage of the speed with which it can be brought online. Without even considering the time for planning and licensing, it can take up to seven years to build a nuclear plant, while natural gas plants take only three.
Additionally, while nuclear is not significantly more expensive than natural gas on a per kilowatt hour basis, individual nuclear power plants require a great deal of upfront financial capital and long-term human capital, making them only an option for wealthier, more established countries. Developing countries besides the biggest ones like China, India, and Brazil need quick, cheap, safe, and cleaner-than-coal sources of electricity.
Natural gas generation can serve as a bridge to the time in a couple of decades when battery technology is adequate enough to allow all electricity to be generated by renewables. While generating electricity would still require burning some fossil fuel, each kilowatt hour of natural gas only releases a little over half the CO2 of coal, and as more renewables are brought online, the total number of kilowatt hours from natural gas could be reduced until it is required only as a last-resort backup for renewables.
Ultimately, nuclear is too expensive and slow to be a widespread alternative to coal. Because infrastructure and regimes for safely managing existing nuclear plants and materials are already in place, there is little to gain from stopping the construction of new nuclear power plants that are already underway, but pairing renewables with natural gas is for now the most effective means available to countries seeking to fulfill their Intended Nationally Determined Contributions. In the long term, this offers a low-carbon path to an eventual switch to the zero-carbon option of renewables and batteries. And in the short-term, it provides countries serious about reducing their emissions a scalable, reliable, and affordable way to do so.