Researchers in the UK have analyzed 25 years of electricity-production and carbon emissions data from 123 countries. Their findings show renewables are considerably more effective than nuclear in reducing carbon emissions from energy generation and that the two technologies tend to get in each other’s way when considered in a joint approach. OCTOBER 5, 2020 MARK HUTCHINS
Renewables offer a surer course to low carbon energy than nuclear, according to a new study.
A study led by the University of Sussex (UoS), in the U.K., has found renewables up to seven times more effective at reducing carbon emissions than nuclear power. The paper concluded nuclear could no longer be considered an effective low carbon energy technology, and suggests that countries aiming to rapidly and cost-effectively reduce their energy emissions should prioritize renewables.
The study, published today in Nature Energy, considers three hypotheses: Firstly, that emissions decline the more a country adopts nuclear; secondly, that emissions decline the more a country adopts renewables; and thirdly, that nuclear and renewables are ‘mutually exclusive’ options that tend to crowd each other out at an energy system level. The hypotheses were tested against 25 years’ worth of electricity-production and emissions data from 123 countries.
The UoS study found little correlation between relative nuclear electricity production and CO2 emissions per capita but did observe a linkage with the per-capita GDP of the nations studied. Countries with high per-capita GDP saw some emissions reduction with increased use of nuclear power, said the researchers, but regions with lower GDP saw CO2 emissions rise with the use of nuclear.
For renewables, however, the data revealed a decrease in CO2 emissions associated with the technology “in all timeframes and country samples” and with no significant linkage to per-capita GDP.
National policy commitments tend to favor one or other option, noted the UoS group, meaning a nuclear focus reduced renewables deployment and vice versa.
“This paper exposes the irrationality of arguing for nuclear investment based on a ‘do everything’ argument,” said Andy Stirling, a professor of science and technology policy at UoS. “Our findings show not only that nuclear investments around the world tend, on balance, to be less effective than renewable[s] investments at carbon emissions mitigation, but that tensions between these two strategies can further erode the effectiveness of averting climate disruption.”
The authors of the study acknowledged their report considered only carbon emissions and said future work should also consider factors such as economic cost; integrated resource planning; reliability; life cycle impacts; risk profiles; waste management; and ecological, political and security impacts.
“While our study can be viewed as a starting point for robust research on the topic of nuclear power, renewables and [the policy] lock-in [of one at the expense of the other], it is not meant to be a finishing point,” the authors stated. “It is an anomaly that the strong claims in favor of particular technologies with which this paper began, have for so long remained so under-evidenced. We encourage others also to address this gap in their future research.”
Even without considering other factors, though, the report’s authors said the emissions data alone was strong enough to recommend nations hoping to trim their energy emissions should focus on renewables rather than nuclear.
“The evidence clearly points to nuclear being the least effective of the two broad carbon emissions abatement strategies and, coupled with its tendency not to co-exist well with its renewable alternative, this raises serious doubts about the wisdom of prioritizing investment in nuclear over renewable energy,” said Benjamin K Sovacool, professor of energy policy at UoS. “Countries planning large scale investments in new nuclear power are risking suppression of greater climate benefits from alternative renewable energy investments.”