The Hydrogen Economy - implications and challenges for wind energy Dr Geoff Dutton Energy Research Unit, CLRC Rutherford Appleton Laboratory (also affiliated to Tyndall Centre for Climate Change Research) BWEA Annual Conference Brighton, 4 October 2002
Wind energy and hydrogen Why hydrogen? The hydrogen economy Where will all the hydrogen come from? Hydrogen production processes Hydrogen storage, transport, and distribution Wind energy and hydrogen Conclusions
Drivers The Hydrogen Economy - Drivers resource depletion global warming (CO 2 ) urban air quality security of supply electricity storage Background BMW clean fleet 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 Hydrogen has more energy per unit mass than any other fuel enables truly zeroemission vehicles is a very diverse fuel and energy carrier but the ultimate energy path is complex and currently expensive
The route to the hydrogen economy Product Performance The Past The Present The Future The internal combustion - engine led to the oil industry The transition is messy The fuel cell may lead to the hydrogen economy Source: Shell Hydrogen 2020? Time
IPCC, Kyoto, RCEP, PIU, and all that International targets and agreements for CO 2 Inter Governmental Panel on Climate Change United Nations Framework Convention on Climate Change (1992) Kyoto Protocol (1997) Developed countries agreed to limit greenhouse gas emissions to 5.2% below 1990 levels by 2010 (UK 12.5% - later revised to domestic target of 20%)
IPCC, Kyoto, RCEP, PIU, and all that UK national studies and targets Royal Commission on Environmental Pollution (2000) recommended a 60% reduction of UK carbon dioxide emissions from 1997 levels by 2050, rising to 80% reduction by 2100 Performance and Innovation Unit The Energy Review (2002) reviewed the options to achieve a low carbon future
PIU Report 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 of 60% 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.
Greenhouse gas emissions UK greenhouse gas emissions Electrical power generation and transport constitute two of the largest sources of man-made greenhouse gas emissions in the UK The switch to natural gas, increased nuclear output, and a small contribution from renewable energy have resulted in a small reduction in emissions from the energy sector The transport sector is projected to increase year on year until it becomes the biggest emitter after 2020
Greenhouse gas emissions by source (MtC) Sector Baseline 2000 2010 2020 Energy supply 67.9 45.6 45.1 47.7 Business 55.9 47.2 46.4 47.4 Transport 35.6 37.9 43.3 48.5 Domestic 23.5 23.3 23.7 24.2 Agr./forestry, land use 23.8 21.9 20.2 18.8 Public 5.0 4.8 4.6 4.5 TOTAL 211.7 180.7 183.3 191.1 Source: Climate Change, The UK Programme, DETR, 2000
The Hydrogen Economy Hydrogen economy = overall (inter)national energy infrastructure based on hydrogen (ideally from nonfossil 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 Nm 3 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 processes Steam methane reforming (SMR) of natural gas Partial oxidation (POX) or 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 Biological photosynthesis or fermentation Other electrochemical and photochemical processes
Hydrogen production - electrolysis of water Electrochemical water-splitting process: H O H + 2 2 1 O 2 2 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
The hydrogen fuel chain renewable electricity
PRIMARY ENERGY METHANE CONVERSION TECHNOLOGY CO 2 CENTRAL STEAM METHANE REFORMER (SMR) CO 2 sequestration feasible NATIONAL GAS GRID STORAGE, DISTRIBUTION & DELIVERY HYDROGEN CO 2 GAS, LIQUID, OR SOLID STATE STORAGE CO 2 sequestration uneconomic END-USE SYSTEM FUEL CELL CHP SYSTEM MICRO GAS TURBINE CHP SYSTEM CO 2 CO 2 ON-SITE SMR ON-BOARD REFORMER WIND GAS TURBINE WIND TURBINE ELECTRIC GRID HYDROGEN ON-SITE ELECTROLYSIS FC VEHICLE Solid state H2 storage IC VEHICLE Liquid H2 storage
Hydrogen and wind energy - autonomous systems Fachhochschule Wiesbaden (1990) 20 kw wind turbine bulk of power electrolysis hydrogen stored commercial 8 kw Otto engine ENEA Casaccia Research Centre (1996) 5 kw wind turbine 2 kw electrolyser poor performance due to oneoff design of electrolyser
Hydrogen and wind energy - autonomous systems Mawson Station, Antarctica installation of modified Enercon E30 turbines in early 2003 900 kw capacity, supplying up to 80% of the station s energy needs by 2007, excess wind energy will be used to run the station s hydrogen generating plant fuel cells will then replace the existing diesel generators Case study for Utsira Island, Norway Windpower Monthly, December 2001
Hydrogen and wind energy - grid-connected systems Motivation alternative to grid reinforcement in rural areas with high wind power potential and weak distribution lines energy buffer to allow more flexible operation of a wind farm (e.g. within the NETA framework) niche market applications Markets hydrogen stored locally and used for regeneration hydrogen transported and sold as fuel supply to commercial processes requiring hydrogen (and oxygen)
Hydrogen and wind energy - grid-connected systems Wind Hydrogen Ltd, UK new joint venture company developing 25 MW wind farm in W of Scotland wind farm linked to 4 MW hydrogen electrolysis system hydrogen stored and used for regeneration in conventional internal combustion gensets (up to 10 MW capacity) electrolysis unit operated as despatchable load hydrogen-fuelled gensets operated as despatchable generators
Hydrogen and wind energy - grid-connected systems Statkraft, Norway involved in study of hydrogen energy storage as an alternative to grid reinforcement Smøla wind farm (Phase I - 40 MW, Phase II - 110 MW) 300 kw hydrogen electrolysis plant hydrogen and oxygen to be used in local fish farm future plans to install a fuel cell for premium power applications (backup power and grid support) Picture courtesy of Statkraft
Hydrogen and wind energy - grid-connected 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 windgenerated electricity Picture by DaimlerChrysler
Hydrogen and wind energy - offshore systems Possible configurations electrical connection between the wind farm and the nearest coastline, then electrolysis of water to produce hydrogen production of hydrogen by electrolysis of desalinated sea water at the offshore wind farm and transmission to shore by gas pipeline production of hydrogen by electrolysis at the offshore wind farm, in situ liquefaction by cooling to 20 K, and then transport to harbour by ship electrical connection between the wind farm and an offshore "hydrogen hub", and transmission to shore by pipeline or liquefaction and transport to harbour by ship
Hydrogen and wind energy - offshore systems Feasibility study for GEO wind farms Dan Tysk (North Sea) and SKY 2000 (Baltic Sea) first technical design and cost estimate failed to find any killer criteria very large scale (400 MWe) compared with largest realised electrolysis system (156 Mwe) gaseous hydrogen pipeline v. liquid hydrogen sea transport liquefaction is a high energy process reducing available capacity of electrolysis plant by around 20% pressurised electrolyser would practically eliminate need for additional compression before pipeline transport lowest initial cost estimates appear to be for pipeline transport
Hydrogen production cost estimates Type of facility Petrol Fuel/Hydrogen price ($/GJ) 3.5 (spot market $20/barrel) 7.9 (pre-tax) 31.0 (70p/litre) Natural gas 1.8 (ave. wellhead 1990-99) 6.0 (wellhead Dec. 2000) Steam methane reforming 5.4 (large plants) - 11.2 (small plants) Partial oxidation 7.0-10.7 Coal gasification 9.9-11.6 Biomass gasification 8.7-13.1 Biomass pyrolysis 8.9-12.7 Methane pyrolysis 5.8 (C revenue) - 10.6 (No C revenue) Steam methane reforming 6.0 (no CO 2 seq.) - 7.5 (with CO 2 seq.) Wind-based electrolysis 11.0 (future 2010) - 20.2 (tech. 2000) Solar-based electrolysis 24.8 (future 2010) - 41.8 (tech. 2000) Source: Gregoire and Padro (1999), Mann et al. (1999), author
Wind energy and hydrogen: economics Wind-hydrogen (and other renewable-hydrogen) costs are case specific and should include consideration of: use of off-peak electricity when wind/solar energy not available sale of electricity from wind/solar energy during peak tarif times (i.e. suspend hydrogen production) available capacity credits and trading arrangements
CO 2 savings from 1 GWh of wind energy Coal-fired power station 1000 t of CO 2 0.3 320 t of CO 2 Fuel cell car Grid electricity Combined cycle gas turbine 430 t of CO 2 345 t of CO 2 0.55 1 GWh of wind energy saves: Nuclear power 0.7 Electrolyser 0 t of CO 2 IC H2 car 160 t of CO 2
How much hydrogen is required? UK passenger cars (2000) : 380 x 10 9 vehicle km Petrol (at 8.4 litres / 100 km) : 31.9 x 10 9 litres Hydrogen (at 1.25 kg / 100 km): 52.8 x 10 9 Nm 3 Electricity (η el = 0.69, LHV) : 230 x 10 9 kwh Wind turbine capacity (40%) : 65,500 MW Natural gas (η SMR = 0.81) : 16.3 x 10 9 Nm 3 UK net electricity (2001) : 365 x 10 9 kwh UK gas production (2001) : 102.0 x 10 9 Nm 3 UK gas reserves (2001) : 1,535 x 10 9 Nm 3
Conclusions There is a need to integrate energy and transport policy A fully developed hydrogen economy would require at least a doubling of electrical energy demand, if the hydrogen is to be derived from renewable, carbon-free sources. The major viable alternative would be large scale steam reforming of natural gas (with carbon sequestration). However, increasing demands on natural gas for space-heating and existing electricity supply will quickly consume indigenous reserves and leave the UK dependent on supplies from Russia and the Middle East, with major implications for diversity and security of supply. Large contributions from biomass and offshore wind would be necessary to fulfil the increased electrical requirement.
Conclusions Niche markets exist already for hydrogen in autonomous systems, in support of wind farms supplying weak grid lines, as a buffer in guaranteeing supply under the NETA framework. Despite high costs, hydrogen is being considered in connection with large wind farm projects in Norway, Germany, and the UK. Automotive companies continue to invest $b in hydrogen prototype vehicles and some have targets of serial production by 2005. Even with sustained growth rates of 40% in the fuel cell vehicle market complete saturation could take 40 years. Although, in terms of climate change objectives, wind energy is currently most valuable in replacing "carbon-hungry" conventional capacity, the wind energy industry should not restrict its horizons to the current electricity market.