Fission or Fossil: Life Cycle Assessment of Hydrogen Production

A comparative hybrid life cycle assessment (LCA) was conducted to evaluate two different methods for hydrogen production. The environmental impacts from nuclear assisted thermochemical water splitting are compared to hydrogen production from natural gas steam reforming with CO₂ sequestration. The results show that the two methods have significantly different impacts. The nuclear alternative has lower impacts on global warming potential, acidification and eutrophication, and much higher impacts from radiation and human toxicity. A weighting procedure is not applied, hence no overall "winner" can be proclaimed. The relative importance of the different impacts remains a challenge for decision makers. Further, the assessment has demonstrated the importance of including services in a comparative assessment. Ordinary process LCA may produce distorted results, since a larger fraction of life cycle impacts may occur outside the system boundaries in one study compared to another due to different fractions of service inputs