What are the greenhouse gas emissions associated with nuclear power?

• A. Nuclear power produces very low emissions once operational, making it a low-carbon energy source
• B. Nuclear power produces high emissions during operation
• C. Nuclear power emits large amounts of methane
• D. Nuclear power emits as much CO2 as coal plants per kWh

Answer: (A)

Nuclear power has very low greenhouse gas emissions during operation because there is no combustion in the reactor, so no CO2 is released while generating electricity. The emissions that do occur come from the fuel cycle (mining and processing uranium, enrichment, fuel fabrication) and from construction, maintenance, and eventual decommissioning. Even when these upstream and lifecycle emissions are included, the total CO2e per kilowatt-hour is much lower than fossil fuels—often listed in the low tens of grams per kWh, versus coal or natural gas that produce hundreds of grams per kWh. This is why the statement that nuclear power produces very low emissions once operational best captures the reality.