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