Air Pollution and Climate-Forcing Impacts of a Global Hydrogen Economy

Abstract

If today's surface traffic fleet were powered entirely by hydrogen fuel cell technology, anthropogenic emissions of the ozone precursors nitrogen oxide (NO x ) and carbon monoxide could be reduced by up to 50%, leading to significant improvements in air quality throughout the Northern Hemisphere. Model simulations of such a scenario predict a decrease in global OH and an increased lifetime of methane, caused primarily by the reduction of the NO x emissions. The sign of the change in climate forcing caused by carbon dioxide and methane depends on the technology used to generate the molecular hydrogen. A possible rise in atmospheric hydrogen concentrations is unlikely to cause significant perturbations of the climate system.

Techno-economic analysis of PEM fuel cells role in photovoltaic-based systems for the remote base stations

“…In comparison, 500 W diesel generator operating 8 h/day emits about one metric ton of CO 2 over a year. Even though fuel cells direct emissions are zero, indirect emissions depend on hydrogen generation technology but even with the most "unclean" process (natural gas reforming) CO 2 emissions can be 60% lower than with the fossil fuels burning in ICE [4,5]. The main drawbacks of fuel cells in comparison with the diesel generators are still the unit cost and problems with hydrogen generation and storage.…”

Impact of a possible future global hydrogen economy on Arctic stratospheric ozone loss

“…This study has been assessed to be unrealistic due to the high leakage rate assumed. 1,2,4,6,47 In contrast, Warwick et al 4 (2004) used only a 5% leakage rate, but the same assumption about the production rates. A scenario proposed by Schultz et al 2 (2003) assumes that only 50% of current fossil-fuel-based technologies will be replaced by hydrogen and estimate a leakage rate between 3% and 10%.…”

“…The latter scenario is regarded as more realistic compared to the previous scenarios and indicates that H 2 at the Earth's surface is raised to 1.1 ppmv. 2,6 To estimate a reliable magnitude of future hydrogen production in a hydrogen-based economy, the future economic and population growth will have to be taken into account. A scenario considering the future hydrogen production until 2100 ''IIASA-SRES B1-H2'' performed by the International Institute for Applied Systems Analysis (IIASA) is based on the ''IIASA-SRES B1'' simulation published by the Intergovernmental Panel on Climate Change (IPCC).…”

“…However, H 2 leakages caused by a possible future global hydrogen economy [1][2][3][4][5][6][7][8] could yield a significant increase in stratospheric water vapor concentrations. 9 An increase of stratospheric water vapor has, in turn, an impact on surface climate and the stratospheric ozone layer, which is of societal relevance.…”

Peer Reviewed: Extracting Hydrogen and Electricity from Renewable Resources

“…Keith and Farrell argue that hydrogen cars comparable to today's passenger vehicles would be too expensive and that the refueling infrastructure alone could cost $5,000/vehicle (3). Others have raised concerns about the effect of hydrogen and water releases on local and global climates (5,6).…”