UN Global report_2019

Box 2-28
Nuclear energy 596
82
There were approximately 450 nuclear power reactors in the world in 2018, producing about 11 per cent
of the total electricity. For each kWh of electricity produced, a life-cycle assessment shows that nuclear
plants emit 4 to 110 grams of equivalent CO 2 , with a median value of 13. 597 That is similar to the life-cycle
assessment emissions of wind and photovoltaic energy, and much lower than for electricity generated by
coal (typically 800 grams) or gas (about 400 grams). If the electricity now produced by nuclear plants was
based on gas or coal instead, world CO 2 equivalent emissions would be higher by approximately 1 or 2
gigatons of CO 2 equivalent emissions per year.
In 2018, the average age of nuclear plants was 30 years, and it continues to increase, as relatively few
new plants are built. After the Chernobyl and Fukushima accidents, and owing to safety concerns after
the terrorist attacks of 9/11, the safety requirements have been reinforced, and the building costs have
significantly increased. The levelized cost per MWh produced by a nuclear plant was estimated by the
Panel’s Working Group III (2014) at approximately $100 in 2012, compared with $70 for gas (see Annex II
of Fifth Assessment Report of Working Group III of the Intergovernmental Panel on Climate Change). In
2012, the estimate was $80 for onshore wind, and 220 for rooftop solar photovoltaic. The International
Renewable Energy Agency estimates $60 and $50, respectively, for 2018.
Even though there are limits to the use of levelized costs for comparing the competitiveness of energy
supply technologies, the observed trends suggest renewable energy will soon be increasingly more
competitive than nuclear energy. The economics of new nuclear plants is heavily influenced by their large
capital costs, and those have had a tendency to increase for safety reasons. That means that few private
investors are willing to invest in them. Adding to the difficulties is the fact that the safety of long-term
management of nuclear waste is still an unresolved issue, public concerns about nuclear safety have not
disappeared and only a small fraction of the risk of accidents is covered by insurance companies, the rest
being assumed by governments.
As a conclusion, existing nuclear power plants have avoided the emission of greenhouse gases, and their
decommissioning should take place only after careful planning, so that they are not replaced by new fossil
fuel power plants. Building new plants seems to be increasingly harder to justify, given the costs involved,
and the decreasing costs of renewables and storage capacities.
Any successful transformation pathway likewise
needs to be shaped by its regional and national
context. In low-income countries in Africa and Asia,
for instance, the emphasis will be on increasing access,
and for at least 50 per cent of the future connections
in sub-Saharan African, off-grid solar systems will be
the most cost-effective solution. In the Arab region,
94.5 per cent of households have access to electricity,
but uptake of renewables is a severe challenge. While
the Latin American region generates 27.6 per cent of its
total final energy consumption from renewables, the
rate of energy efficiency and renewable use is not rising
fast enough in OECD countries to meet the targets
in the Paris Agreement. And a stark figure reminds
us that 2030 Agenda will fail if we allow people to be
left behind: 90 per cent of the over 65 million people
worldwide who have been forcibly displaced from
their homes are living without access to electricity. 598
The gender dimensions of energy transitions are often
599
overlooked but are important (see box 2-29).
Global Sustainable Development Report 2019