Hydrogen production emissions

Takemoto BK, Noble RD, Harrington HM. 1986. Differential sensitivity of duckweeds (Lemnaceae) to sulfite II. Thiol production and hydrogen sulphide emission as factors influencing sulphite phytotoxicity under low and high irradiance. New Phytologist 103 541-548. 

Hydrocarbons (predominantly, NG) are likely to play a major role in hydrogen production in the near- to medium-term future. However, hydrocarbons significantly contribute to anthropogenic C02 emissions into the atmosphere. Spath and Mann [11] estimated that the global warming potential (GWP) of hydrogen production by the SMR process is 13.7 kg C02 (equiv.) per kg of net hydrogen produced. GWP is defined as a combination of C02, CH4, and N20 emissions expressed as C02 equivalence for a 100-year time frame. 

C02 sequestration technology is a viable contender among a set of options to stabilize the atmospheric C02 level over the next few decades (Lackner, 2002). The technical ability to start such a process exists today, but the institutional structures required to reduce C02 emissions are still missing. For hydrogen production, carbon sequestration at the very least will buy time for alternatives to fossil fuels to become competitive. It is, however, equally possible that carbon sequestration removes the major environmental obstacles to the use of fossil fuels in which case it may prove competitive with alternatives for a long time to come. 

Hydrogen production using renewable (locally available) energy sources is seen as an aspirational nearly zero-emission means of energy provision, offering at the same time the possibility of reducing dependence on fossil fuels and the depletion of finite... 

Resources such as biomass could provide a clean and sustainable resource for hydrogen production. As with fossil fuels, the processes that produce hydrogen gas from biomass all create carbon dioxide, but because the biomass acts as a carbon sink during the growing phase, the net carbon emission of the whole cycle is neutral. 

The economics and C02 emissions of the different hydrogen production technologies are summarised in Figs. 10.10 and 10.11, which illustrate the major differences of specific hydrogen-production costs for different technologies and feedstocks. 

What is the ratio of C02 emissions caused by hydrogen production based on fossil energy sources to emissions savings in the transport sector ... 

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