A new breakthrough in hydrogen storage technology could remove a key barrier to widespread uptake of non-polluting cars that produce no carbon dioxide emissions.
UK scientists have developed a compound of the element lithium which may make it practical to store enough hydrogen on-board fuel-cell-powered cars to enable them to drive over 300 miles before refuelling. Achieving this driving range is considered essential if a mass market for fuel cell cars is to develop in future years, but has not been possible using current hydrogen storage technologies.
The breakthrough has been achieved by a team from the Universities of Birmingham and Oxford and the Rutherford Appleton Laboratory in Oxfordshire, under the auspices of the UK Sustainable Hydrogen Energy Consortium (UK-SHEC). UK-SHEC is funded by the SUPERGEN (Sustainable Power Generation and Supply) initiative managed and led by the Engineering and Physical Sciences Research Council (EPSRC).
Fuel cells produce carbon-free electricity by harnessing electrochemical reactions between hydrogen and oxygen. However, today's prototype and demonstration fuel-cell-powered cars only have a range of around 200 miles. To achieve a 300 mile driving range, an on-board space the size of a double-decker bus would be needed to store hydrogen gas at standard temperature and pressure, while storing it as a compressed gas in cylinders or as a liquid in storage tanks would not be practical due to the weight and size implications.
The UK-SHEC research has therefore focused on a different approach which could enable hydrogen to be stored at a much higher density and within acceptable weight limits. The option involves a well-established process called 'chemisorption', in which atoms of a gas are absorbed into the crystal structure of a solid-state material and then released when needed.
The team has tested thousands of solid-state compounds in search of a light, cheap, readily available material which would enable the absorption/desorption process to take place rapidly and safely at typical fuel cell operating temperatures. They have now produced a variety of lithium hydride (specifically Li4BN3H10) that could offer the right blend of properties. Development work is now needed to further investigate the potential of this powder.
"This could be a major step towards the breakthrough that the fuel cell industry and the transport sector have waited for," says UK-SHEC's Project Co-ordinator Professor Peter Edwards of the University of Oxford. "It's due to SUPERGEN's vision of combining many of the leading groups in the UK to tackle this, arguably the biggest challenge for the development of hydrogen fuel cell vehicles. This work could make a key contribution to helping fuel cell cars become viable for mass-manufacture within around 10 years."
Notes for Editors
Fuel cells are a key technology which could assist the emergence of a 'hydrogen energy economy' that uses hydrogen, rather than carbon-based fossil fuels, as its main energy carrier. They offer particular potential in the transport sector, which is a major source of the carbon dioxide emissions from fossil fuel combustion that are the main contributor to climate change. An average new petrol-fuelled car currently produces over 3 tonnes of CO2 a year.
Professor Bill David from the ISIS Facility at the Rutherford Appleton Laboratory notes that: "The combination of rapid materials synthesis and the rapid structural characterisation capabilities at the ISIS neutron source and the ESRF and Diamond synchrotron sources is crucial to the UK playing a leading role in discovery and development of novel hydrogen storage materials."
Dr Paul Anderson from the University of Birmingham adds: "Active collaborations through UKSHEC have been crucial in facilitating the rapid characterisation of new materials synthesised in labs such as ours in Birmingham."
A major report in 2004 concluded that using hydrogen in vehicles could, on its own, enable the UK to meet its Kyoto targets for CO2 reductions ('A Strategic Framework for Hydrogen Energy', published by Etech, Element Energy and Eoin Lees Energy).
Launched in 2003, SUPERGEN is a multidisciplinary research initiative that aims to help the UK meet its environmental emissions targets through a radical improvement in the sustainability of power generation and supply. SUPERGEN is managed and led by EPSRC in partnership with the Biotechnology and Biological Sciences Research Council (BBSRC), the Economic and Social Research Council (ESRC), the Natural Environmental Research Council (NERC) and the Carbon Trust. A total of 13 research consortia are now at work or have been announced, in the following areas:
Marine energy - energy from the seas around our coastline.
- Future network technologies - ensuring the continuance of a reliable supply of power to the UK.
- Hydrogen energy - producing, storing, distributing and using sustainable hydrogen as an energy carrier.
- Biomass, biofuels and energy crops - using fast-growing crops as a renewable fuel supply.
- Photovoltaic (solar cell) materials - generating electrical energy from sunlight using advanced wafer silicon and thin film devices.
- Conventional power plant lifetime extension - extending the useful lives of our existing power stations.
- Fuel cells - clean, highly efficient devices for producing power.
- Highly distributed power systems - assessing the impact of smaller generators and incorporating these into the grid.
- Energy storage - developing new materials to advance rechargeable lithium ion battery and supercapacitor technologies.
- Excitonic solar cells - exploring the potential for the next generation of photovoltaic devices, focusing on organic and dye sensitised photovoltaic systems.
- Wind energy - harnessing one of the UK's most abundant natural resources as a major source of renewable energy.
- Energy infrastructure - developing the UK transmission and distribution network to meet the challenges of decentralised and intermittent electricity generation and life extension.
- Biofuel cells - fuel cells that mimic, reproduce or use biological systems.
The brochure "SUPERGEN - Powering the Future" can be downloaded at http://www.
The 'SUPERGEN 1' multidisciplinary research consortia have all been awarded a further four years of funding following peer review of both their past work and their proposed future programmes. The awards are:
- SUPERGEN Marine £5.5M
- SUPERGEN Biomass £6.4M
- UK Sustainable Hydrogen Energy Consortium £6M
- FlexNet: SUPERGEN consortium on future network technologies £7M
These decisions ensure that the UK will continue to be at the forefront of sustainable power generation research.
In the next quarter the SUPERGEN II consortia (Photovoltaic and Plant Lifetime Extension) will be invited to prepare renewal proposals. These will be peer reviewed and a panel will consider the proposals in the early autumn.
UK-SHEC is led by the Universities of Oxford and Bath. UK-SHEC partners are as follows: University of Bath, University of Birmingham, University of Glamorgan, Greater London Authority, University of Nottingham, University of Oxford, Queen Mary, University of London, Policy Studies Institute and University of Salford. Collaborators include: BOC Group, BP, STFC Rutherford Appleton Laboratory, Corus UK Ltd, DSTL, Johnson Matthey, Ilika Technologies Ltd, QinetiQ, Shell Global Solution UK and Tetronics Ltd.
The Engineering and Physical Sciences Research Council (EPSRC) is the UK's main agency for funding research in engineering and the physical sciences. The EPSRC invests around £740 million a year in research and postgraduate training, to help the nation handle the next generation of technological change. The areas covered range from information technology to structural engineering, and mathematics to materials science. This research forms the basis for future economic development in the UK and improvements for everyone's health, lifestyle and culture. EPSRC also actively promotes public awareness of science and engineering. EPSRC works alongside other Research Councils with responsibility for other areas of research. The Research Councils work collectively on issues of common concern via Research Councils UK. Website address for more information on EPSRC: www.epsrc.ac.uk/
For more information, contact:
Professor Peter Edwards, University of Oxford, Tel: 01865 272646, E-mail: firstname.lastname@example.org
Three images (lithiumhydride.jpg, carousel.jpg and atoms.jpg) are available from the EPSRC Press Office, contact Natasha Richardson, e-mail: email@example.com, tel: 01793 444404.
Suggested captions for images:
Lithiumhydride.jpg: "High hopes for hydrogen storage: this variety of lithium hydride could help unlock the door to a low-carbon future."
Carousel.jpg: "Searching for a solution - experimental technique to determine the structure of materials with possible hydrogen storage potential."
Atoms.jpg: "The future in store: hydrogen atoms can be absorbed effectively into the new storage material - hydrogen (H) atoms are shown in green, lithium (Li) atoms in dark grey, nitrogen (N) atoms in blue and boron (B) atoms are in grey and inside the pyramids."