Hydrogen Storage in Energy Applications:
Challenges and Opportunities
Tim Mays
Department of Chemical Engineering
University of Bath, UK
University of Bath
The University of Bath is one of the UK’s leading universities with a vibrant and innovative academic community with an international outlook.
Its friendly campus overlooks the beautiful UNESCO
World Heritage City of Bath.
Bath is consistently ranked in the top ten of ALL national university league tables and is 3rd behind only Cambridge and Oxford in the 2013 Sunday Times league table.
The University has over 15,000 students including 3,500
international students.
Aberdeen
Outline
Context
Hydrogen energy
H2FC SUPERGEN
Storage
Outlook
Outline
Context
Hydrogen energy
H2FC SUPERGEN
Storage
Outlook
Context – Energy Sustainability and Security
Population and economic growth
Increased energy demand
Pollution and climate change
Running low on conventional fuels
Challenges to energy security
More intermittent renewables
Can hydrogen help?
What are the opportunities?
Outline
Context
Hydrogen energy
H2FC SUPERGEN
Storage
Outlook
water
(H2O)
biomass (– CHyOz )
fossil
fuels (– CHx )
Hydrogen is the third
commonest element on the
Earth’s surface but almost
all of it is contained in
chemical compounds
Lots of Hydrogen
Hydrogen Now
~65 Mt of H2 produced pa globally
~95% made from fossil fuels, ~50 % by high-
temperature steam reforming of natural gas
CH4+ 2H2O → 4H2+ CO2 ~5% made by electrolysis of water
2H2O → 2H2 + O2
Main (current) uses are in chemical processing
conversion of crude oil to transport fuels
manufacture of ammonia and methanol
hydrogenation of oils and fats
D
e–
Hydrogen Energy Basics
hydrogen + oxygen → water + energy
H2(g) + ½ O2(g) → H2O + E
E = 120 – 142 MJ kg-1 heat (combustion) = 1.23 V electrical potential + 24 MJ kg-1 heat (fuel cell) +
Only material product of above reaction is water
Compare: hydrocarbon + oxygen → water + carbon dioxide + …
A lot of energy per unit mass of hydrogen
Compare: 40 – 55 MJ kg-1 for combustion of hydrocarbons
Many possible sources of hydrogen
Hydrogen can only ever yield as much energy as was used to
produce it in the first place
Hydrogen moves energy around (like electricity);
strictly it is an energy vector or carrier
No CO2 at point of use
Lots of energy per unit mass
Creation of new industries and support of current ones
… but challenges remain including
Technical
Sustainable production
Storage and distribution
End use
Socio-economic
Cost and affordability
Awareness and acceptability
Safety, regulation, codes and standards
Hydrogen Energy Benefits and Challenges
Hydrogen energy chain
geothermal, tides,
(nuclear, fossil)
Sustainable Hydrogen Energy Chain
Outline
Context
Hydrogen energy
H2FC SUPERGEN
Storage
Outlook
• Delivery of Sustainable Hydrogen
• 14 consortia
• c.£62m support since 2003
• Over 40 institutions
• Consortia phase finishes 2014
EPSRC SUPERGEN Consortia (2003-14)
EPSRC SUPERGEN Hubs (2011- )
• New "hubs" and associated grand challenges
• Networks, Marine, Solar, Bioenergy and
Hydrogen & Fuel Cells (H2FC) hubs funded
to date
http://www.h2fcsupergen.com/
£4.1M for Hub (2012-7)
£5.3M for five associated challenge projects (2013-7)
H2FC Structure
H2FC Workpackages
Outline
Context
Hydrogen energy
H2FC SUPERGEN
Storage
Outlook
sustainable production of H2 → store / distribute → energy conversion
5 kg H2 gas (ambient)
~ 5 m diameter vessel
5 kg H2 liquid (triple point)
~ 0.5 m diameter vessel
The Hydrogen Storage Challenge
Molecular Hydrogen Density
0 10 20 30 40 50 60 70 80 90 1000
10
20
30
40
50
60
70
80
90
100
solid
solid data:
Silvera, Rev. Mod. Phys. 52 (1980) 393
liquid and real gas data:
Leachman et al., J. Phys. Chem. Ref. Data 38 (2009) 721
solid at 4 K, limit of 0 MPa
liquid at solid-liquid-vapour triple point
liquid at liquid-vapour critical point
liquid at normal boiling point, 20.3 K
real gasideal gas
real gas
de
nsity / k
g m
-3
pressure / MPa
77 K
298 K
ideal gas
liquid–
(31.2 kg m-3)
(77.0 kg m-3)
state-of-art
compressed gas
for transport
Energy Storage
Physical storage molecular or di-hydrogen, H2
Chemical storage atomic, ionic, covalent hydrogen
Physical and Chemical Hydrogen Storage
Solid / liquid
Compressed gas
Pipelines
Underground
Containment in porous solids
…
H2O
hydrocarbons
NH3
LiNi5Hx
MgH2
…
Hydrogen Storage Options
More Hydrogen Storage Options
Hythane pipelines
Natural or excavated underground caverns, mines,
salt domes, aquifers, depleted oil/gas fields
Chemical carriers (ammonia, …)
WP6.1 – Tim Mays (Chemical Engineering, Bath)
Physical storage in nanoporous materials
WP6.2 – David Book (Metallurgy & Materials, Birmingham)
Chemical storage in metal borohydrides
This sub-WP will study advanced nanoporous materials such as
carbide-derived carbons, metal-organic frameworks, polymers of
intrinsic microporosity and inorganic (including carbon) nanotubes
integrated into high-pressure tanks to improve storage capacity [1]
with possible additional benefits in integrated tank design [2] such
as strength and conformability.
to 70 MPa
MOF-5
[1] Bimbo, N., Ting, V. P., Hruzewicz-Kołodziejczyk, A. and Mays, T. J.,
2011. Farad Discuss, 151, 59.
[2] US DOE Annual Merit Review, 2011.
[3] Reed, D. and Book, D., 2011. Cur Opin Solid S M, 15, 62.
The US DOE has recently highlighted the potential and novelty of
metal borohydride stores [2]. This sub-WP will investigate
intermediate phases in Mg(BH4 )2 (c.12 wt% hydrogen) and related
high-capacity systems to reduce cycling temperatures and
improve reversibility. Novel in situ experiments [3] will test the
potential benefit of these storage materials at high pressures.
Mg(BH4)2
[ Zn4O (1,4-benzenedicarboxylate)3 ]
H2FC Storage Research – Workpackage 6
Outline
Context
Hydrogen energy
H2FC SUPERGEN
Storage
Outlook
Outlook
Hydrogen is an attractive, sustainable energy vector
It will play a role in future, low-carbon diversified energy systems
Storage is one major challenge
Storage solutions will depend on application
Transport Light- and heavy-duty vehicles
Buses
Trains
Boats and ships
Aerospace
Niche (forklift trucks, …)
…
Portable /
small-scale Mobile 'phones
Laptops and PCs
…
Static Space heating
Uninterruptable power supplies
Electricity storage (local to national scales)
…
Hydrogen Storage Opportunities Research, development,
demonstration, deployment
Advanced, low-cost high-pressure tanks
in transport applications (Type IV+ … ?) Optimised materials, processing and storage conditions
Balance of plant considerations
Conformability
Full life-cycle energy and materials analysis
Hybrid high-pressure / solid-state materials storage
in transport applications (Type V … ?) Incorporation of solid-state storage materials into tanks
Reduce pressure for same amount of gas
More gas for same pressure
Multifunctional – mechanical and thermal benefits
Hythane grid
Replaceable tanks?
Large-scale
underground storage Alternative carriers
20-25 July 2014
Hosted by the University of Salford, UK
at The Lowry, Salford Quays
MH2014
http://www.mh2014.co.uk/
Acknowledgements
Thank you