1. Efficient Hydrogen Refueling Station Design NHA, Long Beach, CA 5 th of May 2010 Alistair Wardrope ITM POWER | Efficient Hydrogen Refueling Station Design

2. Contents Energy Storage | Clean Fuel  Developing Refueling Technology  Design for Efficiency  Simulate for Efficiency

3. Developing Refueling Technology Energy Storage | Clean Fuel  Developing Refueling Technology A brief history of past, current and future refueling technology

4. Developing Refueling Technology Green Box - 2008 First attempt at vehicular hydrogen refueling Energy Storage | Clean Fuel

5. Developing Refueling Technology Energy Storage | Clean Fuel HPRU - 2009 Onsite electrolyser and PV Cascade refueling 10 kg @ 350 bar refueling Based at ITM, Sheffield, UK

6. Developing Refueling Technology Energy Storage | Clean Fuel HFuel - 2010 Fully integrated refueling solution

7. Developing Refueling Technology Energy Storage | Clean Fuel HPac HFill HPoint HFuel HFuel Integrating to existing designs into a new product

8. Design for Efficiency Energy Storage | Clean Fuel  Design for Efficiency Major factors in hydrogen refueling station efficiencies

9. Design for Efficiency Energy Storage | Clean Fuel Company Technology Refueling Design File

10. Design for Efficiency Energy Storage | Clean Fuel Refueling Station Efficiency Production methods  Natural gas reformation  Electrolysis, PEM, AE, etc. Processes post-production  Gas clean-up  Gas compression  Gas storage  Gas dispensing

11. Design for Efficiency Energy Storage | Clean Fuel Interaction Between Components Electrolyser to gas clean up  Availability of components and associated cost vs. pressure Palladium filter to compressor  Inlet pressure to compressor has significant impact on energy consumed by compressor Compressor to cylinders  Specification of cylinders must satisfy refueling duty cycle, however over-specification may cause drop in efficiency

12. Simulate for Efficiency Energy Storage | Clean Fuel  Simulate for efficiency Cost effective methods of designing an efficient refueling station

13. Simulate for Efficiency Energy Storage | Clean Fuel Effect of compressor inlet pressure

14. Simulate for Efficiency Energy Storage | Clean Fuel Energy losses through compression Energy required  Product of ratio of inlet/outlet pressures and required flowrate How to determine power consumption  Using manufacturers data it is possible to determine to flow characteristics of a compressor  Energy consumption per kg of H2 is a product of compressor power rating and compression time

15. Simulate for Efficiency Energy Storage | Clean Fuel

16. Simulate for Efficiency Energy Storage | Clean Fuel Effect of cylinder sizes

17. Simulate for Efficiency Energy Storage | Clean Fuel

18. Simulate for Efficiency Energy Storage | Clean Fuel Cylinder Selection Does size matter?  No...  The energy demand on the compressor does not change with increasing cylinder size when filling cylinders to their original pressures after a vehicle fill What size do cylinders need to be?  Approximately 6 times the vehicle cylinder mass and volume are required; for 350 bar filling; 50% @ 250, 33% @350 and 17% @450 bar as a baseline distribution of volumes

19. Simulate for Efficiency Energy Storage | Clean Fuel

20. Simulate for Efficiency Energy Storage | Clean Fuel Compromise to reduce compression losses Electrolyser  As electrolyser outlet pressure increases, compression costs decrease at the expense of higher electrolyser costs. Palladium filter  Compromise between low pressure drop across membrane and surface area (and associated cost) of palladium Storage and refueling pressure  Reduce pressures as far as reasonably possible

21. Conclusion Energy Storage | Clean Fuel Design for success Understand interactions between components  Appreciate design requirements and constraints Characterise components and simulate  Where possible create accurate mathematical models Generic adaptable platform  Apply to range of refueling station designs and sizes

22. End of Presentation Energy Storage | Clean Fuel