1. Sustainability Assessment of H 2 Pathways Ben M c Lellan Chemical Engineering Chemical Engineering

2. Introduction Why Hydrogen? Why Sustainability Metrics? Purpose of this work

3. General Life Cycle Flowsheet ExtractionProductionPurificationUtilisation Transport Transport / Storage CO2 CaptureSequestration

4. Sustainability Metrics Aim: to assess and compare the different pathways in terms of environmental sustainability Potential Environmental Impacts Not location-specific (IChemE, TRACI) EB = Environmental burden W N = Mass of emission W H2 = GJ Hydrogen Produced PF = Potency Factor PEI = Potential Environmental Impact

5. Sustainability Metrics Specific Sustainability Metrics Take location-specific factors into account SEI = Specific Environmental Impact SEB = Specific Environmental Burden K = unitless location-specific coefficient

6. Case Study Two Source Extraction Points – one for NG, one for Coal Options of on-site hydrogen production or at point of usage hydrogen production Comparison of Source Transport, Source Extraction and Hydrogen Production Impacts

7. Case Study - Details Table 1: Hypothetical Test Case Data FeedstockCoal NG Process Gasification (IGCC) Steam Reforming Location #1#2#3#4 Distance from Source Onsite (3km) 200kmOnsite (3km) 450km Transport Type Rail Pipeline Mean Annual Days of Rain 92669553 Average soil pH 5.87.35.76.4 Population within 20km 10752749558125749

8. Global Warming Impacts CO2 and hydrocarbon emissions from each stage given as CO2 equivalence K value based directly on emissions

9. Global Warming Impacts OnsiteOffsiteCoal#1#2 NG#3#4

10. OnsiteOffsiteCoal#1#2 NG#3#4

11. Acidification Potential NOx and SOx emissions weighted in terms of SO 2 equivalence PEI from simple addition of emissions (factor of 0.7 for NOx) K value based on annual rainfall and soil pH in the region Rain factor: Where f rain is the mean annual days of rain. Soil factor: (pH >0)

12. Acidification Potential OnsiteOffsiteCoal#1#2 NG#3#4

13. Human Health Impacts Mainly from H2 Production – only emissions assessed here Particulates Assumed to have a major impact only in the surrounding 20km radius K value based on population in surrounding area

14. Human Health Impacts OnsiteOffsiteCoal#1#2 NG#3#4

15. Global Warming Potential - Comparison of Stages SituationExtractionTransportProduction # 10.225.05E-0734.54 # 20.223.50E-0334.54 # 32.59E-034.45E-0722.05 # 42.59E-038.80E-0322.05 Global Warming Specific Environmental Impacts (kg CO 2 -eq / GJ H 2 )OnsiteOffsiteCoal#1#2 NG#3#4

16. Summary of Results Global Warming Acidification Human Health PEISEIPEISEIPEISEI #1221113 #2111411 #3442224 #4332322 Ranking of Overall Environmental Impacts (1- Highest, 4- Lowest) As expected because Global Warming is non- location-specific Ranking changes with SEI due to local population Ranking changes with SEI due to different soil pH / rainfall conditions OnsiteOffsiteCoal#1#2 NG#3#4

17. Conclusions Sustainability metrics were used successfully Some adjustments need to be made to enable more wide-ranging use (inclusion of social/economic factors, distance/time variable models) The data and model require refining The importance of specific indicators demonstrated

18. Conclusions Sustainability Metrics can be used to compare different technology impacts, different life cycle stages and different locations A useful tool, but the process needs to be improved so that it is more scientific

19. Hydrogen Production – Summary of Results Global WarmingAcidificationHuman Health SituationPEISEIPEISEIPEISEI #1 34.54 0.02910.0270.19250.0008 #2 34.54 0.029100.1925 #3 22.0514.07 0.0075 0.0640.0002 #4 22.0514.07 0.00750.00390.0640.001

20. Transport and Extraction – Summary of Results Global Warming Situati on PEISEI #1 7.62 #2 7.62 #3 0.2390.0075 #4 0.2390.0075 Global WarmingAcidification Situatio n PEISEIPEISEI #1 0.00423.96E-058.18E-087.47E-08 #2 0.350.276.82E-060 #3 0.00312.23E-055.25E-11 #4 0.44 7.89E-094.11E-09 Transport Impacts Extraction Impacts