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Alternative Energy Sources. Bill Pyke Hilbre Consulting Limited October 2012. Delivered to:. Alternative Transport Fuels Hydrogen, Engine Developments & Biofuels. HYDROGEN COMMERCIAL & ENVIRONMENTAL CONCLUSIONS. Current Situation.
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Alternative Energy Sources Bill Pyke Hilbre Consulting Limited October 2012 Delivered to: Alternative Transport Fuels Hydrogen, Engine Developments & Biofuels
Current Situation • 95% of global hydrogen is produced from fossil fuels • 500 billion cubic metres /year of hydrogen compares with 2,865 billion cubic metres of natural gas • Hydrogen production from fossil fuels with CO2 capture and storage is likely to provide the bulk of hydrogen required in the next 30-50 years
Current Situation (2) • 5% of hydrogen is produced through electrolysis in localities where a overproduction of renewable electric power exists that cannot be effectively distributed through the electric grid • Liquefied hydrogen important, since pipelines limited. Only 500 miles in the United States • Hydrogen then used as balancing power or in transport
Hydrogen Process Pathways Source: John A. Turner, Science 1999, Shell 2004
Technology Status in Hydrogen Production Mature, commercial processes • Steam Reforming • Gasification • Liquefaction • Pipelines • Electrolysis
Hydrogen Storage and Distribution Issues • High cost of new networks • Only 70 hydrogen filling stations globally • Storage as Compressed or Liquefied Hydrogen • Compressed Hydrogen higher cost storage vessels. Safety Issues • Liquefied ; Low temperature -2530C, boil-off, heat transfer, pressure and safety issues!
Commercial Cost Issues for a Hydrogen Economy Competitive costs against traditional fuels Cost of CO2 Sequestration in Steam Reforming Electrolysis Cost (Electricity cost) to generate hydrogen at commercial rates Distribution infrastructure in hydrogen transport fuel network Additional safety systems, materials and processes
Evolution of Hydrogen Sources? Source: Air Products
Environmental Issues Hydrogen’s Image Hydrogen must be dangerous Highly Combustible Hydrogen 120 MJ/kg Gasoline 40 MJ/kg Nat Gas 55 MJ/kg Extra safety precautions needed
Environmental IssuesCO2 Sequestration Carbon sequestration is the only option to make hydrogen a zero-carbon fuel Decentralized hydrogen production implies the practical loss of the sequestration option Hydrogen is then just an efficient way to use fuel. But the CO2 issue remains!!
Synthesis Gas – “Syngas”An Important Intermediate Methane is the primary constituent of natural gas. In most cases it comprises >80% of the gas reserves Utilised in the formation of syngas- a mixture of oxides of carbon (CO and CO2 ) together with elemental hydrogen Two chemical processes are used in the formation of syngas- steam reforming and partial oxidation
The Steam-Methane Reformer A steam-methane mixture is passed over a catalyst. Catalyst—usually nickel dispersed on alumina support. Operating conditions: 850-940°C, 3 MPa. Heat for the chemical reaction is provided by feedstock natural gas. Not suited to the production of syngas for onwards conversion to middle distillates. The process is more used in the petrochemical industry- the onwards conversion to methanol or ammonia Conversion of syngas generated by the steam reformer tends to have H2/CO ratio of about 2 to 3 as per the reaction below:- CH4 + H2O = CO + 3H2 Endothermic, takes in/absorbs heat.
Partial Oxidation Oxygen reacts directly with gas CH4 + ½O2 = CO + 2H2 The key process in gasification of coal, coke, methane and biomass Operates at high temperatures (1200-1500°C) Exothermic, the reaction generates heat Need to eliminate tars, nitrogen, methane, sulphur
Water-Gas Shift Reaction Water-gas shift reaction is the conversion of carbon monoxide into CO2 and hydrogen CO + H2O =H2 + CO2 Uses catalysts at low temperatures Enhances production of Hydrogen Endothermic
Hydrogen From Electrolysis 2 MW Turbine can produce 100 tonnes/year of hydrogen via electrolysis
Electrolysis to Produce Hydrogen Electricity + 2H2O = 2H2 + O2 2 types • Alkaline electrolysis • In production since 1920s, well established • Potassium Hydroxide electrolyte to decrease resistance • PEM (Proton Exchange Membrane) electrolysis • Solid membrane acts as electrolyte • No cleanup step necessary
Economics of Hydrogen ProductionElectrolysis Currently only 5% of the hydrogen produced annually is derived from the electrolysis of water Cost of the electricity used in the electrolytic process makes it uncompetitive with the steam-reforming process The electricity can cost three to four times as much as steam-reformed natural gas feedstock
The Hydrogen power process utilises technology proven at this scale around the world Source: BP
Process Uses proven reforming technology to manufacture syngas from methane (CH4) [BP Trinidad] Uses proven shift reaction technology to generate H2 and CO2 Uses proven amine capture technology to capture and remove CO2 [In Salah, Algeria] Hydrogen-fired Combined Cycle Gas Turbine (CCGT) proven and warranted by vendors Miller Field naturally contains CO2 so facilities are suitable for handling well fluids with high CO2 concentrations
Commercial/Technical Issues PRODUCTION • Reduce cost of production to compete with coal & gas • Research & develop CO2 sequestration • Reduce the cost of sustainable production; Wind, solar DEVELOPMENTS Prove new water splitting technologies STORAGE • Improve storage capacity - compressed, liquid, hydrides, etc. • Prove distribution & infrastructure at next level
The Future? • The Tata Nano • Relies on a 33 hp two-stroke petrol engine • Sales Price £1,300 • Per Capita income rising rapidly in developing Asia • Indian market 1 billion people
Improvements in Automotive Fuels 1990-2012 • Tetra-ethyl lead banned and replaced • Sulphur emissions reduced from 300ppm to <100ppm now headed to <10ppm • Aromatics reduced, nearly eliminated • Particulates nearly eliminated • Methyl Tertiary Butyl Ether (MTBE)- an additive implicated in groundwater contamination and now banned in U.S. • Volatile Oil Compounds reduced
Vehicle PollutantsHealth Effects • NOx NO2 can be directly toxic to lung tissue by forming acids with water in the lungs. When mixed with volatile organic compounds, NO2 forms ground-level ozone, which is a major component of smog • Particulates: Can exacerbate all respiratory and cardiovascular diseases. PM10, produced diesel engines and petrol engines, is the aerodynamic diameter capable of entering the lung airways. PM10 is partially comprised of PM2.5, which is small enough to reach the alveoli • Volatile organic compounds (VOC): Emitted by vehicle engines, they combine with nitrogen oxides to form ozone. Effects are long term including adverse neurological, reproductive and developmental effects as well as having associations with cancer • Ground-level ozone: A major component of smog, formed from VOCs and nitrogen oxides. Exposure to elevated levels can lead to severe coughing, shortness of breath, pain on breathing, lung and eye irritation and greater susceptibility to respiratory diseases. High levels can also exacerbate asthma attacks
EU Maximum Sulphur Road Fuels: 1990-2010 Source: UKPIA
Vehicle numbers are set to grow rapidly in the Non-OECD 26 million vehicles 5 million vehicles 8 million vehicles 224 million vehicles 96 million vehicles
Transport Evolution Mass Commercialisation Fuel Cell Hybrids (FCHVs) Electric Vehicles (EVs) Plug-in Hybrids (PHVs) Hybrids Internal Combustion Engine Improvements 2030 2020 2035 2010 2015 2025
Projected Future Light Vehicle Sales by Category Source: IEA, WEO, November 2010
2012 The Outlook for Energy: A View to 2040, ExxonMobil, January 2012
Anode Cathode Fuel Cell: Principle of Operation e- H+ H2 O2 H2 2H+ + 2e- ½ O2 + 2H+ + 2e- H2O Electrolyte Source: Caltech Overall: H2 + ½ O2 H2O
The Nissan Leaf Mass Market Electric Car
Biomass as Fuel • Pros and Cons • Biomass to Heat and Power • Transport Fuels • Bioethanol • Sources • Key players • Secondgeneration development and yields • Biodiesel • Sources • New technologies BTL
Outline • Sources • Availability • Advantages/Disadvantages • Challenges • Cost Parameters
Fuels for Transport Electrical Power CHP
National Initiatives • EU Renewable Fuels Obligation (RTFO) • from 3.5% in 2010/11 to 5% in 2013/14 • further increases in the level of biofuels to 10%, subject to review in 2014, under the Renewable Energy Directive • U.S. Renewable Fuel Standard (RFS) • requires 7.5 billion gallons of renewable fuel to be blended into gasoline by 2012 • Brazil Bioethanol provides 24% of fuel consumption • China 3rd largest biomass producer
Environmental Appeal Utilises solar energy and converts some of it into biomass –a versatile fuel Removes some CO2 from the atmosphere in the process Provides habitat for native species Multiple products when harvested
Disadvantages Competing with land for food production Ensuring Continuous supply Carbon neutral ?? Transport costs ?? Drying to specification is energy-intensive Biomass moisture content often 40-60%, needs to be 10-15% Storage Issues Impurities and toxins