storage overview

Overview of Storage DevelopmentDOE Hydrogen Program: 

Overview of Storage Development DOE Hydrogen Program George Thomas Sandia National Laboratories Livermore, CA Hydrogen Program Review San Ramon, CA May 9-11, 2000 Safe, efficient and cost-effective storage is a key element in the development of hydrogen as an energy carrier

Hydrogen storage requires something more than a can or a bucket: 

Hydrogen storage requires something more than a can or a bucket Hydrogen has the highest mass energy density of any fuel: 120 MJ/kg (LHV) 144 MJ/kg (HHV) however At ambient conditions (300 K, 1 atm.): the energy content of 1 liter of H2 is only 10.7 kJ, three orders of magnitude too low for practical applications. Issues: 1. What are the options available for storage? 2. What are the theoretical limits to storage density and how close can we come? 3. How do we organize a development program to achieve adequate stored energy in an efficient, safe and cost-effective manner?

Mass energy densities for various fuels: 

Mass energy densities for various fuels Increasing molecular wt.

Maximum energy density is achievedin liquid state: 

Maximum energy density is achieved in liquid state

Hydrogen energy content in liquid fuels: 

Hydrogen energy content in liquid fuels Hydrogen density is nearly the same in all fuels. This narrow range suggests a natural benchmark for comparison of storage performance.

Maximum storage densities (w/o system) : 

Maximum storage densities (w/o system) High pressure gas ambient temperature 3600 psi: 2.0 5000 psi: 2.75 cryogenic system 150 K: 3.5 20 K: 8.4 Liquid hydrogen 8.4 Reversible storage media carbon structures nanotubes ? fullerenes ? hydrides intermetallics 10.8 - 12.0 alanates 8.25 composite materials ? Chemical methods Eff. gasoline methanol liquid fuel + reformer 50%: 6.6 5.9 75%: 9.9 8.9 off-board reprocessing ? Energy Density MJ/liter

Programmatic guidelines: 

Programmatic guidelines A balanced program between scientific discovery and engineering validation is needed. Portion of program invested in high risk approaches. Collaboration with industry at all levels. International partnerships beneficial. Leverage off other programs. Program should not downselect technologies too early Options should be fully explored. Different technologies suited for different applications. Realistic goals should be set as metrics for progress. Evaluate goals on a continuing basis continue to refine roadmap

Materials Development: 

Materials Development Carbon nanotubes M. Heben, NREL near-term goal: ~6 wt.% synthesis, processing, hydrogen absorption/desorption Carbon fullerenes R. Loutfy, MER feasibility of fullerene-based storage Alanate hydrides C. Jensen, Univ. of Hawaii NaAlH4 : 5.5 wt.% hydrogen capacity catalysts, properties Hydride development K. Gross, SNL near-term goal: 5.5 wt.% at <100 C (NaAlH4) bulk synthesis, scaled-up beds, characterization, safety studies Catalytically enhanced storage C. Jensen, Univ. of Hawaii new start Polymer dispersed metal hydrides T. Jarvi, United Technologies new start

Pressure Tank Development: 

Pressure Tank Development Lightweight tanks F. Mitlitisky, LLNL goal: >10 wt.% 5000 psi Conformable tanks R. Golde, Thiokol Propulsion Co. high pressure tanks with improved packing efficiency cryogenic hydrogen vessels S. Aceves, LLNL design and testing for improved volume density Composite tank testing B. Odegard, SNL comparison of high pressure hydrogen tank failure to other fuels. CNG, gasoline, methanol.

Engineering Validation: 

Engineering Validation PV/electrolysis/metal hydride K. Sapru, ECD modeling and integration of storage with renewable energy sources Metal hydride/ organic slurry R. Breault, Thermo Power chemical hydride for PEMFC vehicles hydrogen transmission and storage Fuelcell/hydride powerplant G. C. Story, SNL for underground mine and tunneling locomotive Thermal hydrogen compression D. DaCosta, Ergenics, Inc. new start

Other hydrogen storage programs (US) : 

Other hydrogen storage programs (US) DOE/OTT Fuels for Fuel Cells Program (P. Devlin) Parallel development of fuel processor and onboard H storage. DOE/OIT Low cost hydrides for mine vehicles (SRTC) Part of Mining Industry of the Future initiative. IEA Task 12 will be completed Oct. 2000 New task being formed: Advanced Solid and Liquid State Hydrogen Storage Materials (G. Sandrock) Industry Projects

Other hydrogen storage programs (non US) : 

Other hydrogen storage programs (non US) Canadian Projects Alanates (A. Zaluska, McGill Univ.) Nanocrystalline Mg-based hydrides (Hydro-Quebec) Carbon adsorption (IRH) European Projects liquid hydrogen storage (BMW) refueling station (BMW) WENET (Japan) Metal-H complex ions (S. Suda, Kogakuin Univ.) others

Some highlights from this year: 

Some highlights from this year Continuing progress in nanotubes high purity synthesis and processing methods. > 6 wt.% appears feasible. Important progress achieved on alanates 5.5 wt.% at low temperatures appears feasible. Continued improvement in lightweight and conformable tanks more efficient packing of high pressure tanks integration of storage with applications PV system mine vehicle Three new starts catalyst enhanced storage polymer dispersed hydride thermal hydrogen compression