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Hydrogen Economy
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Hydrogen: The Fuel of the Future?
Institute of Physics, London, 11 November 2003
Dr Geoff Dutton
Energy Research Unit,
CLRC Rutherford Appleton Laboratory
UK Hydrogen Energy Network (H2NET) www.h2net.org.uk
The Hydrogen Economy
Why hydrogen? The hydrogen economy Where will all the hydrogen come from? Hydrogen
production processes Hydrogen storage, transport, and distribution Hydrogen end-use systems Hydrogen technology futures Conclusions
The Hydrogen Economy - Drivers
Drivers resource depletion global warming (CO2) urban air quality security of supply electricity storage
BMW clean fleet Background
energy crisis in 1970s led to initial concept development followed by technology driven demonstration projects in
1980s and 1990s industrial commitment from the late 1990s, particularly
relating to fuel cells and automotive applications
The Hydrogen Economy - Drivers
but the ultimate energy path is complex and currently expensive
Hydrogen has more energy per unit
mass than any other fuel enables truly zero-
emission vehicles is a very diverse fuel and
energy carrier
PIU Report (2002)
There is the long term prospect that the technology for powering vehicles by fuel cells fed on hydrogen will ultimately provide a substitute for oil.
it is possible to deliver reductions in carbon emissions of60% provided sufficient energy efficiency measures are adopted, the electricity system has very low carbon emissions, and major progress is made towards a low carbon transport system, probably based on hydrogen. Such transitions are highly unlikely without strong policy attention to the development of low carbon options.
Energy White Paper (2003) 3 challenges
Environmental protection The threat of climate change is real Adopt target to cut emissions to 60% of current levels by 2050
Resource depletion Dependent on imported energy for 75% of our total needs by 2020 Without new nuclear build only Sizewell B will be operating by 2025 Natural gas will need to be imported from Norway, Russia, the Middle
East, North Africa, Latin America
Energy infrastructure modernisation New investment in generating capacity has waned during 1990s European regulations likely to force modernisation or closure of old
coal-fired plant Renewables will become a more significant source of electricity (10%
by 2010, but only an aspiration of 20% by 2020) Major investments needed in the fuel delivery infrastructure
Energy White Paper (2003) 4 goals
To put ourselves on the path to cut the UKs CO2 emissions by 60% by 2050 (real progress by 2020)
To maintain the reliability of energy supplies To promote competitive markets in the UK and beyond (to raise
the rate of sustainable economic growth and improve our productivity)
To ensure that every home is adequately and affordably heated
The Hydrogen Economy
Hydrogen economy = overall (inter)national energy infrastructure based on hydrogen (ideally from non-fossil primary energy sources)
Hydrogen is a storage and transmission vector for energy from renewable (or nuclear) power stations allowing both utilities and consumers increased flexibility
Hydrogen production - current status
Hydrogen is currently used almost exclusively as an industrial chemical ~500 billion Nm3 produced annually worldwide (Air Products
is largest producer with > 50 plants, 7 pipeline systems totalling > 340 miles)
48% is produced by steam reforming of natural gas used for ammonia production, fertiliser manufacture,
methanol production, refinery use for desulphurisation fuel for space exploration
Hydrogen production
Steam methane reforming (SMR) of natural gas Partial oxidation (POX) / reformation of other carbon-based fuels Coal gasification (IGCC) Biomass gasification Pyrolysis Dissociation of methanol or ammonia Electrolysis of water
if the source of electricity is renewable energy then the net emissions of carbon dioxide are zero
Thermo-chemical splitting of water Biological photosynthesis or fermentation Other electrochemical and photochemical processes
Hydrogen production - SMR
Hydrocarbonfeeds
Hydro-desulphurisation
H2Products
HTS/LTSSHIFT PSA
FUEL
Steam
ReformerProcess
GasBoiler
EXPORTSTEAM
REFORMING SHIFTCH4 + H20 3H2 + CO CO + H20 H2 + CO2
880 oCSource : Air Products
Hydrogen production - SMR
Tosco Martinez SMR, CA Source : Air Products
Hydrogen production - electrolysis of water
Electrochemical water-splitting process:
222 21 OHOH +
Commercial electrolysers typical efficiency 75% Operating pressures up to 50 bar (< high pressure cylinders)
need for additional compression Improve efficiency by operating at higher T Develop high pressure electrolysers
Hydrogen production cost estimates
SMR
Fuel cost (EUR/km)
CO2 emissions (kgCO2 / km)
Petrol (untaxed) Petrol (taxed)
Electrolysis from grid electricity
increasing naturalgas price
carbon dioxidesequestration
Biomass Solar el.Wind el.
Hydrogen storage
Pressurised gas underground chambers advanced high pressure composite cylinders
Liquefied hydrogen Transmission by pipeline Chemical (methanol, ammonia, etc.) Reversible metal hydride systems Carbon nanotubes US DOE hydrogen goal 7.5 wt.% of H2
The Periodic Table of the Chemical ElementsThe mass of each element isindicated by elevationabove the plane
M. O. Jones, and P. P. Edwards, University of Birmingham,
Stored H2 per mass and per volume: metal hydrides, carbon nanotubes, petrol and other hydrocarbons
Schlapbach and Zttel, Nature, 15 Nov 2001
Volume of 4 kg of hydrogen compacted in differentways, with size relative to the size of a car.
Mg2NiH4 LaNi5H6 H2 (liquid) H2 (200 bar)Schlapbach and Zttel, Nature, 15 Nov 2001
Hydrogen distribution and transport
Hydrogen is conventionally distributed in: gaseous form cylinders or large pressure vessels liquefied form by tanker liquefied form by pipeline
Large scale hydrogen pipeline distribution is feasible but is likely to be very expensive
Existing natural gas pipeline network could be used: dilution with H2 by up to 10% technical problems likely to prevent higher concentrations
being allowed logistic problems of changeover
Hydrogen distribution and transport
2,800 28,000 280,000 2,800,000Usage m3/Day
Pipeline
Large Onsite Plants
Small Onsite Plants
Liquid Hydrogen
Tube Trailer
Source : Air Products
Hydrogen end-use systems
Hydrogen fuelled internal combustion engines limited by Carnot efficiency improved efficiency by up to 20% compared with gasoline
since both compression ratio and ratio of specific heats increased
loss of power due to lower energy content in air/fuel mixture NOx emissions can be limited to order of magnitude less
than from petrol engine development work needed to develop fuel injection
techniques and re-design combustion chamber and cooling system topography to suit hydrogen (rather than simply converting existing IC engines)
Hydrogen end-use systems
Fuel cells use chemical process to convert H2 into electrical energy
and heat not limited by Carnot efficiency high power density (i.e. high power output per unit area,
volume, or mass) different types of cell distinguished by their different
electrolytes and different operating temperatures high efficiency across most of output power range
(especially at low load) compare with IC engine over whole drive cycle
balance of plant is a barrier
Hydrogen end-use systems - fuel cell typesType of fuel cell Electrolyte
Mobile ion
Operatingtemperature
Typical efficiencyAlkaline Potassium hydroxide
(85 wt% high T)(35-50 wt% low T)
OH-
50 - 90(200) oC
Proton exchangemembrane (PEM)
PolymericH+
50 - 125 oC
40% +Phosphoric acid(PAFC)
Orthophosphoric acidH+
~ 220 oC
Molten carbonate(MCFC)
Lithium/potassiumcarbonate mixture
CO32-
~ 650 oC
Solid oxide(SOFC)
Stabilised zirconia
O2-
500 - 1000 oC
Direct methanol Sulphuric acid or polymer 50 - 120 oC
Fuel cell markets
Fuel Cells
Mobile Stationary Portable
Propulsion
Auxiliary power
Industrial CHP 100 kW 10 MW
Residential CHP 5 kW 100 kW
Consumer electronics
Military hardware (backpack)
Hydrogen end-use systems
Hydrogen end-use systems
Clean Urban Transport for Europe (CUTE) 30 fuel cell powered buses
in 10 European cities each city has a different
hydrogen supply chain in Hamburg the hydrogen
will be supplied by electrolysis using wind-generated electricity
Hydrogen transition pathways
Characteristics of large technical systems (with Dr Jim Watson, SPRU)
Consequences of the scale of hydrogen systems on environmental benefits, dangers of lock-in, knock-on effects on other energy sectors
Object of study in current Tyndall Centre project
Lessons from the development of large technical systems (1)
Large technical systems have three distinct features (Thomas Hughes, 1983): technical (e.g. power stations, transmission lines) and non-technical
(e.g. distribution companies, environmental laws) component sets horizontal and vertical interconnection of components (change in one
part of the system has knock-on effects in others) control component based on technical system, economic system
(e.g. wholesale power market), and regulatory system (e.g. OFGEM) Large technological systems enshrine powerful vested interests The hydrogen energy economy could be seen as a direct
challenge to the current energy system
Lessons from the development of large technical systems (2)
The early development of the electricity supply industry from Edisons Electric Light Company (1878) chaotic with many small power companies electric lighting was considerably more expensive than gas lighting
and so had to be sold on novelty and prestige value the growth of electric motors for use by industry finally decided
matters the battle of the systems between AC and DC transmission lasted
for several years and was not always based on scientific arguments following victory of AC transmission there were still many small
private companies, many using different frequencies, voltages, and standards
to economies of scale in the 1920s need for load management advances in steam turbine technology
Lessons from the development of large technical systems (3)
The electricity supply industry after the 1920s: In the US, large numbers of small networks were bought up and
connected using common frequency and voltage standards in private utilities
In the UK, a national grid structure emerged in similar way, to be nationalised in 1947
Economies of scale reinforced the case for centralisation, whether state-owned or private monopolies
The modern industry is dominated by vested interests, (sometimes uncomfortably) balanced by a growth in the power of the regulator
CONVERSION TECHNOLOGY
STORAGE, DISTRIBUTION & DELIVERY
END-USE SYSTEMPRIMARY ENERGY
METHANE
GAS, LIQUID, OR SOLID STATE STORAGE
FUEL CELL CHP SYSTEM
ELECTRIC GRID
ON-SITE ELECTROLYSIS
NATIONAL GAS GRID
HYDROGEN
CENTRAL STEAM METHANE REFORMER (SMR)
CO2 CO2 sequestration feasible
MICRO GAS TURBINE CHP
SYSTEM
WIND WIND TURBINEIC VEHICLE
Liquid H2 storage
CO2
ON-BOARD REFORMER
ON-SITE SMR
CO2
CO2 sequestration uneconomic
GAS TURBINE
CO2
HYDROGEN FC VEHICLE Solid state H2
storage
CO2 savings from 1 GWh of wind energy
1 GWh of wind energy
saves:
Coal-fired power station 0.3
1000 t of CO2
Grid electricity
430 t of CO2
Combined cycle gas turbine
0.55
345 t of CO2
Nuclear power
0 t of CO2 IC H2 car
140 t of CO2
Fuel cell car
270 t of CO2
Electrolyser0.7
How much hydrogen is required?
UK passenger cars (2000) : 380 x 109 vehicle km Petrol (at 8.4 litres / 100 km) : 31.9 x 109 litres Hydrogen (at 1.25 kg / 100 km): 52.8 x 109 Nm3
Electricity (el = 0.69, LHV) : 230 x 109 kWh Wind turbine capacity (40%) : 65,500 MW Natural gas (SMR = 0.81) : 16.3 x 109 Nm3
UK net electricity (2001) : 365 x 109 kWh UK gas production (2001) : 102.0 x 109 Nm3
UK gas reserves (2001) : 1,535 x 109 Nm3
The route to the hydrogen economyP
rodu
ct P
erfo
rman
ce
The Past The Present The Future
-
The transitionis messy
Time
2020 ?
The internal combustion engine led to the oil
industry
The fuel cell may lead to the
hydrogen economy
Source: Shell Hydrogen
EC High Level Group on Hydrogen and Fuel Cells
European Commission, Hydrogen Energy and Fuel Cells: A Vision For Our Future, June 2003
EC High Level Group on Hydrogen and Fuel Cells
European Commission, Hydrogen Energy and Fuel Cells: A Vision For Our Future, June 2003
Publications
Dutton, A.G., The Hydrogen Economy and Carbon Abatement Implications and Challenges for Wind Energy, Wind Engineering, Vol. 27, No. 4, p. 239-256, 2003
Dutton, A.G., Watson, J., Bristow, A., Page, M., Pridmore, A., Integrating Hydrogen into the UK Energy Economy, 1st European Hydrogen Energy Conference (EHEC), Grenoble, France, 2-5 September 2003
Dutton, A.G., Hydrogen Energy Technology, Tyndall Working Paper No. 17, April 2002 (available on-line at http://www.tyndall.ac.uk/publications/working_papers/wp17.pdf)
Dutton, A.G., Bleijs, J.A.M., Dienhart, H., Falchetta, M., Hug, W.,Prischich, D., Ruddell, A.J., Experience in the design, sizing, economics, and implementation of autonomous wind-powered hydrogen production systems, Int. J. of Hydrogen Energy, Vol. 25, p. 705-722, 2000
http://www.tyndall.ac.uk/publications/working_papers/wp17.pdfhttp://www.tyndall.ac.uk/publications/working_papers/wp17.pdfConclusions
The carbon dioxide emissions benefits of different hydrogen fuelchains must be compared with those from alternative fuels.
It is necessary to consider electrical energy production, heating, and supply of transport fuels in a single framework.
A fully developed hydrogen economy in the transport sector wouldrequire at least a doubling of electrical energy demand, if the hydrogen is to be supplied exclusively by electrolysis.
Accelerated installation of renewable, carbon-free electricity generating capacity (biomass, offshore wind, wave, tidal, and possibly nuclear) would be required to fulfil the increased electrical requirement.
The major conventional alternative would be large scale steam reforming of natural gas (with carbon dioxide sequestration).
Innovative hydrogen production methods need to be developed e.g. hydrogen production from biological processes and by thermo-chemical water-splitting reactions.
Thank-you for listening!
For more information, please visit:UK Hydrogen Energy Network:
www.h2net.org.uk
Or e-mail: [email protected]
http://www.h2net.org.uk/mailto:[email protected]: The Fuel of the Future?The Hydrogen EconomyThe Hydrogen Economy - DriversPIU Report (2002)Energy White Paper (2003) 3 challengesEnergy White Paper (2003) 4 goalsThe Hydrogen EconomyHydrogen production - current statusHydrogen productionHydrogen production - SMRHydrogen production - SMRHydrogen production - electrolysis of waterHydrogen production cost estimatesHydrogen storageStored H2 per mass and per volume: metal hydrides, carbon nanotubes, petrol and other hydrocarbonsHydrogen distribution and transportHydrogen distribution and transportHydrogen end-use systemsHydrogen end-use systemsHydrogen end-use systems - fuel cell typesFuel cell marketsHydrogen end-use systemsHydrogen end-use systemsHydrogen transition pathwaysLessons from the development of large technical systems (1)Lessons from the development of large technical systems (2)Lessons from the development of large technical systems (3)How much hydrogen is required?The route to the hydrogen economyEC High Level Group on Hydrogen and Fuel CellsEC High Level Group on Hydrogen and Fuel CellsPublicationsConclusions