Going Green:
The Growing Role of
Permanent Magnets in
Renewable Energy Production
and Environmental Protection
Gareth P Hatch, Ph.D.
Director of Technology
Dexter Magnetic Technologies, Inc.
Presented at the Magnetics 2008 Conferenceheld in Denver, Colorado, USA, in May 2008
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Gareth Hatch
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Going Green:The Growing Role of
Permanent Magnets inRenewable Energy Productionand Environmental Protection
Gareth P. Hatch, Ph.D.Director of Technology
Dexter Magnetic Technologies Inc.
http://www.dextermag.com
Magnetics 2008
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Outline
! Introduction! The Challenge of Global Energy Usage! Renewable Energy Resources & Devices
! Wind! Hydro! Ocean! Solar
! PM Devices for Environmental Protection! Future Challenges! Appendices
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Introduction
!Units of measurement: energy consumption!Metric tonne of oil equivalent (toe)!!Barrel of oil equivalent (boe)!!Based on average efficiencies of energy conversion!1 tonne oil " 6.8 bbl oil!1 toe " 42 GJ " 11.6 MW·h
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Outline
! Introduction! The Challenge of Global Energy Usage! Renewable Energy Resources & Devices
! Wind! Hydro! Ocean! Solar
! PM Devices for Environmental Protection! Future Challenges! Appendices
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The Challenge of Global Energy Usage
Source: OECD / IEA [2007]
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The Challenge of Global Energy Usage
Source: OECD / IEA [2007]
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The Challenge of Global Energy Usage
Source: REN21 [2006]
Sources of Global Energy Supply
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The Challenge of Global Energy Usage
!Power output of conventional power stations
2 – 10 GWHydro1 – 2 GWFuel oil1 – 2 GWCoal
1 – 1.5 GWNuclear0.5 – 1 GWNatural gas
Typical OutputEnergy Source
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The Challenge of Global Energy Usage
!Global energy consumption will only increase!Projected growth of over 50% from 2005 to 2030!Projected AAGR of 1.6% between 2005 and 2030!From 6.5 billion people in 2005 to 8.1 billion by 2030
Sources: OECD / IEA [2006 & 2007] & United Nations [2006]
22.7 TW
17.1 Gtoe
2030
17.0 TW
12.8 Gtoe
2010
18.7 TW
14.1 Gtoe
2015
15.1 TWConsumption rate
11.4 GtoeGlobal energy consumption
2005Energy Source
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The Challenge of Global Energy Usage
!Electricity demand will also accelerate!Recall that 1 toe ! 11.6 MW·h!Per OECD / IEA [2006]:
!Estimated 14.4 PW"h in 2004 – 16% of total consumption!Projected 28.1 PW·h in 2030 – 21% of total consumption
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The Challenge of Global Energy Usage
Source: OECD / IEA [2006]
Projected World Electricity Demand by Region
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The Challenge of Global Energy Usage
!Obviously demand is not the only factor!Finite supply of fossil fuels!Geopolitics of energy [in]dependence!Connection between foreign & energy policies!Climate change considerations!Pollution control!Political mandates as economic drivers
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The Challenge of Global Energy Usage
! “The energy future which we are creating is unsustainable. If we continue as before, the energy supply to meet the needs of the world economy over the next twenty-five years is too vulnerable to failure arising from under-investment, environmental catastrophe or sudden supply interruption”. --- OECD / IEA [2006]
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Outline
! Introduction! The Challenge of Global Energy Usage! Renewable Energy Resources & Devices
! Wind! Hydro! Ocean! Solar
! PM Devices for Environmental Protection! Future Challenges! Appendices
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Renewable Energy Resources & Devices
!What is renewable energy ?!“Renewable energy is derived from natural processes
that are replenished constantly. In its various forms, it derives directly from the sun, or from heat generated deep within the earth”. --- OECD / IEA [2003]
!Electricity and heat generated from resources such as:!Wind!Hydro!Ocean [includes tidal – derived from Earth – Moon interaction]!Solar!Biomass!Geothermal
! Includes biofuels and hydrogen derived from renewable resources
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Outline
! Introduction! The Challenge of Global Energy Usage! Renewable Energy Resources & Devices
! Wind! Hydro! Ocean! Solar
! PM Devices for Environmental Protection! Future Challenges! Appendices
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Renewable Energy Resources & Devices
Wind
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Renewable Energy Resources & Devices
!Wind energy!Currently most significant area for potential PM usage!Archer & Jacobson [2005]: 72 TW global potential
!Primarily land-based or near-shore stations!Resolve [2005]: 900 GW in US offshore wind potential
!Enough to replace all conventional power stations in the US
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Renewable Energy Resources & Devices
Source: Archer & Jacobson [2005]
Mean annual wind speed in Europe, extrapolated to 80 m
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Renewable Energy Resources & Devices
Source: Archer & Jacobson [2005]
Mean annual wind speed in North America, extrapolated to 80 m
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Renewable Energy Resources & Devices
!Total installed wind power capacity in 2007
Source: Global Wind Energy Council [2008]
100.094.1TOTAL13.813.0Rest of World2.32.1Portugal2.52.4UK2.62.5France2.92.7Italy3.33.1Denmark6.46.1China8.58.0India
16.115.1Spain17.916.8US23.622.2Germany
% TotalPower [GW]
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Renewable Energy Resources & Devices
!How does a wind turbine work?
Source: GE [2008]
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Renewable Energy Resources & Devices
Source: Nordex [2008]
! Nordex N80 - generates 2.5 MW ! Rotor weight: 50 tonnes! Rotor diameter: 80 m! Rotor speed: 10-20 rpm! Tower height: 80 m! Rating: 3-25 m/s [5.6 – 56 mph]! Gearbox weight: 18.5 tonnes! Gearbox ratio: 1:68! Generator weight: 12 tonnes! Generator speed: 750-1300 rpm! Generator type: asynchronous double-fed [i.e. non-PM]
Conventional Large Wind Turbine
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Renewable Energy Resources & Devices
!Wind energy!To what does 2.5 MW approximate?
!Power for 750 average single family US homes!Power for 1,250 average single family EU homes!Power for 5,000 average single family Chinese homes
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Renewable Energy Resources & Devices
Source: EWEA [2007]
! e.g. REpower 5M – 5 MW! e.g. Enercon E126 – 7 MW! Power ! swept area of blades! Power ! cube of wind speed! Provides efficiencies of scale! Geared turbines reaching limit! Issues of weight & reliability! Next step: PM generators! Allows for smaller gearbox
Trend Towards Larger Turbines
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Renewable Energy Resources & Devices
Source: Multibrid [2008]
! Multibrid M5000 - generates 5 MW ! Rotor weight: 76.6 tonnes! Rotor diameter: 116 m! Rotor speed: 6-15 rpm! Rating: 4-25 m/s [8.9 – 56 mph]! Total nacelle weight: 199 tonnes! Gearbox ratio: 1:10! Generator speed: 60-150 rpm! Generator type: synchronous PM
Geared Wind Turbine with PM Generator
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Renewable Energy Resources & Devices
Source: Multibrid [2008]
Geared Wind Turbine with PM Generator
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Renewable Energy Resources & Devices
!Wind energy!Final step: remove the gearbox altogether!!Results in direct drive turbine with PM generator
!Hub connected directly to generator shaft!Requires much larger diameter generator!Eliminates gearbox! Increased reliability! Increased mechanical efficiency
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Renewable Energy Resources & Devices
Source: Scanwind [2008]
! Scanwind 3500 DL – generates 3.5 MW! Uses The Switch PMR3150 direct drive PM generator ! Rotor diameter: 91 m! Rotor speed: 10-20 rpm! No gearbox required! Capable of variable speed
Gearless Wind Turbine with PM Generator
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Renewable Energy Resources & Devices
Source: The Switch [2008]
! Contains > 2,000 kg Nd-Fe-B!Br ! 1.2 T [12 kG]!Hcj ! 1.5 MA/m [19 kOe]
! Operating temp " 80 #C! Approx 0.6 kg / kW produced
The Switch PMR3150 PM Generator
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Renewable Energy Resources & Devices
Source: The Switch [2008]
The Switch PMR3150 PM Generator
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Renewable Energy Resources & Devices
Source: Treehugger.com [2006 & 2008]
! From MagLev Wind Turbine Tech! Claims ability to produce 1GW! Vertically aligned rotor! Magnetic levitated using PMs! Minimal friction losses! Scant information available!! 0.3 kW Chinese maglev turbines available
The Shape of Things to Come??
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Outline
! Introduction! The Challenge of Global Energy Usage! Renewable Energy Resources & Devices
! Wind! Hydro! Ocean! Solar
! PM Devices for Environmental Protection! Future Challenges! Appendices
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Renewable Energy Resources & Devices
Hydro
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Renewable Energy Resources & Devices
!Hydro!Largest “conventional” source of renewable energy!Potential 100 GW + in new construction
!e.g. Three Gorges Dam – 22.5 GW!Significant growth in small hydro [ < 10 MW ]
!Approximately 8-10% of total!Access to previously inaccessible sources!Common in “run-of-river” applications!Principal area of application for PM devices
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Renewable Energy Resources & Devices
!Total installed hydro power capacity in 2006
Source: BP [2007]
100.0845TOTAL32.5275Rest of World2.118Sweden2.622Venezuela3.126Japan3.731India3.933Norway5.849Russia9.681US
11.597Brazil11.597Canada13.7116China
% TotalPower [GW]
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Renewable Energy Resources & Devices
Source:Wikimedia Common [2007]
Cross-section of large hydro facility
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Renewable Energy Resources & Devices
!Conventional large hydro turbines!Generally non-PM generators!Francis turbines
!most commonly used turbine for large hydro!90%+ efficiencies!Head range of tens to hundreds of meter
!Kaplan turbines!better suited for low head / high flow!Adjustable blades!Can achieve 90%+ efficiency
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Renewable Energy Resources & Devices
Source: Voith-Siemens & Wikimedia Common [2007]
750 MW Francis turbine for hydro
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Renewable Energy Resources & Devices
Source:Voith-Siemens [2007]
154 MW Kaplan turbine for large hydro
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Renewable Energy Resources & Devices
Source: VA TECH Hydro [2005]
Bulb Turbine for Small Hydro
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Renewable Energy Resources & Devices
Source: VA TECH Hydro [2007]
Bulb Turbine with PM Generator
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Renewable Energy Resources & Devices
Source: VA TECH Hydro [2007]
! VA TECH Hydro ECOBulb – 1.02 MW ! Other units 0.5 – 5 MW! Single or double regulated axial design! Typical turbine speed: 150 rpm! Discharge: 15-100 m3/s! Head: 2-15 m! Direct coupled PM generator! Requires no gearbox! No external cooling required! Low profile – low impact
Bulb Turbine with PM Generator
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Renewable Energy Resources & Devices
Source: VA TECH Hydro [2007]
! ECOBulb 4MW PM rotor ! Up to 97% efficient design! Uses “high energy” Nd-Fe-B! Other details “proprietary”! Other variations [e.g. rim mount]
Bulb Turbine with PM Generator
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Outline
! Introduction! The Challenge of Global Energy Usage! Renewable Energy Resources & Devices
! Wind! Hydro! Ocean! Solar
! PM Devices for Environmental Protection! Future Challenges! Appendices
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Renewable Energy Resources & Devices
Ocean
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Renewable Energy Resources & Devices
!Ocean energy!Estimated 7.5 PW potential in the oceans [OSU 2005]!Relatively low present capacity!Technology 15-20 years behind wind [OSU 2007]!Seawater 835 times more dense that air!Variety of methods of energy generation
!Wave motion!Tidal stream!Tidal barrage
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Renewable Energy Resources & Devices
!Ocean energy!Wave motion
!Exploits both potential and kinetic energy!Estimated potential of up to 2 TW world wide [DoE 2007]!Less than 2 MW actually installed [OSU 2007]!Most powerful waves in 40! – 60! latitudes!Tend to be on western coasts!Peaks of 100 kW/m crest length
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Renewable Energy Resources & Devices
Source: Centre for Renewable Energy Resources [2006]
Wave Power Levels in kW/m Crest Length
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Renewable Energy Resources & Devices
Sources: UMIP, Finavera & Pelamis [2006-8]
Variety of Wave-Based Devices
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Renewable Energy Resources & Devices
Source: Wave Dragon [2005]
! Wave Dragon – proposed 4MW! Water stored in reservoir ! Released via turbines! Total width: 260 m! Working wave range: 0.7 m +! Weight: 22,000 tonnes! 16 X 250 kW Kaplan turbines! Turbine speed: 125-250 rpm! Directly coupled PM generator
Overtopper Device with PM Generators
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Renewable Energy Resources & Devices
Sources: Florida Tech [2005], Prado et al [2006] & AWS Ocean Energy [2007]
! Archimedes Wave Spring! Fixed to sea bed + floater! Pilot plant – 2 MW output! Floater: 9.5 m diameter! PM linear generator! Stroke length: 7m! Stroke speed: 2.2 m/s! Generator weight: 100 tonnes! 2008 installation - Orkney
Submerged Point Absorber with PM Linear Generator
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Renewable Energy Resources & Devices
Source: NY Times, OSU & NSF [2007]
Floating Point Absorber PM Linear Generator Buoy
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Renewable Energy Resources & Devices
Sources: OSU [2007]
! OSU SeaBeav 1 ! 1 kW prototype! Tested in 2007 off Oregon! Further tests underway! Uses Nd-Fe-B magnets
Floating Point Absorber PM Linear Generator Buoy
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Renewable Energy Resources & Devices
!Ocean energy!Tidal stream
Source: GSFC / NASA [2002]
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Renewable Energy Resources & Devices
Source: Marine Current Turbines [2008]
! MCT SeaGen – 1.2 MW! Installed Apr 2008 in N. Ireland! Secured to seabed! Total mass: 1,000 tonnes! Twin rotors: 16 m diameter! Rotors can be pitched 180!! Wings can be raised above sea level! Geared, non-PM generator
Geared Axial Flow Tidal Stream Turbine
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Renewable Energy Resources & Devices
Source: OpenHydro [2007]
! OpenHydro Open-Centre Turbine! Test system - 250 kW! Installed at Orkney Jan 2007! No gearbox required! PM generator in outer rim! Uses venturi to increase speed! Will be scaled to MW range! Few other details available
Axial Flow Tidal Stream Turbine with PM Generator
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Renewable Energy Resources & Devices
Source: WIPO / OpenHydro [2008]
Axial Flow Tidal Stream Turbine with PM Generator
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Outline
! Introduction! The Challenge of Global Energy Usage! Renewable Energy Resources & Devices
! Wind! Hydro! Ocean! Solar
! PM Devices for Environmental Protection! Future Challenges! Appendices
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Renewable Energy Resources & Devices
Solar
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Renewable Energy Resources & Devices
!Solar energy!Earth's surface receives 89 PW power from the Sun!Annual mean insolation varies across the globe
!Australian Outback: 5.9 kW·h/m2/day !Helsinki, Finland: 2.4 kW·h/m2/day
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Renewable Energy Resources & Devices
[Values in kW·h/m2/day, normal to sun, on worst day of the year]
Source: EFuture [2007]
World Insolation Map
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Renewable Energy Resources & Devices
!Total installed photovoltaic [PV] capacity in 2006
Source: IEA-PVPS [2007]
100.05.85TOTAL3.70.22Rest of World0.70.04South Korea0.70.04France0.90.05Italy0.90.05Netherlands1.20.07Australia1.20.07China2.10.12Spain
10.60.62US29.21.81Japan48.92.86Germany
% TotalPower [GW]
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Renewable Energy Resources & Devices
!Total installed thermal solar capacity in 2006
Source: REN21 [2008]
100.0105.1TOTAL2.02.2Rest of World0.20.2South Africa1.11.2India1.21.3Australia1.71.8US2.12.2Brazil3.63.8Israel4.54.7Japan6.36.6Turkey
12.813.4EU64.567.7China
% TotalPower [GW]
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Renewable Energy Resources & Devices
Source: Wikimedia Commons [2007]
! Air naturally heated in large greenhouse! Convection causes air to rise! Air escapes through tall tower! Passes through turbines! Connected to PM generators
Novel Concept: Solar Updraft Tower
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Renewable Energy Resources & Devices
Source: Enviromission [2007]
! Prototype tested 1982-1989! Located in Manzanares, Spain! Tower height – 195 m! Tower diameter – 10 m! Greenhouse – 0.045 km2 [11 acres]! Generated 50 kW
Solar Updraft Tower
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Renewable Energy Resources & Devices
Sources: Enviromission [2007] & T-Mation [2007]
! Larger versions now being proposed ! To be located in Spain or Australia! Tower height – 1,000 m! Low efficiency - 0.5%! Greenhouse – 38 km2 [9,390 acres]! Roof height – 10 -16 m! Air heated by 35 !C! Air flow of 15 m/s [34 mph]! Projected 200 MW via 32 turbines! Can use “greenhouse” as a greenhouse!! One proposal – PM turbine rim bearings
Solar Updraft Tower
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Renewable Energy Resources & Devices
Source: T-Mation [2007]
Solar Updraft Tower
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Outline
! Introduction! The Challenge of Global Energy Usage! Renewable Energy Resources & Devices
! Wind! Hydro! Ocean! Solar
! PM Devices for Environmental Protection! Future Challenges! Appendices
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PM Devices for Environmental Protection
!PM devices for environmental protection!Three examples of technologies enabled by PMs
!Reducing the environmental impact of drilling!Preventive maintenance of oil & gas pipelines!Emergency shut down of subsurface oil wells
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PM Devices for Environmental Protection
Source: National Petroleum Council [2007]
Reducing the Environmental Impact of Drilling
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PM Devices for Environmental Protection
Source: Mackenzie Gas Project [2007]
! a.k.a. “slant” drilling! Access where vertical drilling not possible! Grouping of up to 30-40 well heads! Increased exposed section length! Real-time data transmitted to surface! Direction of drill bit adjusted in 3D
Directional Drilling
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PM Devices for Environmental Protection
!Directional drilling!Real-time data transmitted back to surface
!Measurement while drilling [MWD]!Logging while drilling [LWD]
!Recent development – MRIL-WD!Magnetic resonance imaging – logging while drilling!MRI a.k.a. nuclear magnetic resonance imaging
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PM Devices for Environmental Protection
Source: Oilfield Review [2003]
PM-Based NMR Logging While Drilling
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PM Devices for Environmental Protection
Source: Oilfield Review [2003]
! Uses Sm-Co magnets! Exposed to 300 !F / 20 kpsi! Oriented parallel to tubular! Creates static polarizing field! High magnetic gradient! Unit inserted into drill string! Instrumentation also inserted
PM-based NMR Logging While Drilling
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PM Devices for Environmental Protection
!Preventive maintenance of oil & gas pipelines!Corrosion & mechanical defects are a major concern!Regular pipeline inspection required!Rapid, non-destructive method needed! Inspection tools known as “smart PIGs”!Magnetic flux leakage [MFL] used to detect anomalies
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PM Devices for Environmental Protection
Source: Kogas [2006]
! Pipeline completes circuit with tool! Defects cause anomalies! Sensors collect magnetic data! Positioning data also recorded! Some systems now use GPS
PM-based MFL Pipeline Inspection Tools
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PM Devices for Environmental Protection
Source: OnStream [2007]
! PM magnetizer module! Typically Nd-Fe-B magnets! Instrumentation modules! Sensors collect magnetic data! Positioning data also recorded! Some systems now use GPS
PM-based MFL Pipeline Inspection Tools
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PM Devices for Environmental Protection
!Emergency shut down of subsurface oil wells!Offshore deepwater oil wells becoming more critical!Surface-controlled subsurface safety valves [SCSSVs]!Potential “super” wells as deep as 40,000 feet!Highly corrosive, high pressure / high temp conditions
!Up to 400 !F, 30 kpsi!Presents challenges for conventional SCSSVs
! Internal wellbore pressure!Elastomeric seals
! Ideal solution isolates valve piston from the wellbore!Solution – PM linear coupler
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PM Devices for Environmental Protection
Source: Halliburton [2008]
! Halliburton Depthstar! Uses Sm-Co magnets! 100% metal-to-metal sealing! No moving seals within wellbore! Simplified hydraulics! Increase life of the well
SCSSSV Using PM Linear Coupler
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Outline
! Introduction! The Challenge of Global Energy Usage! Renewable Energy Resources & Devices
! Wind! Hydro! Ocean! Solar
! PM Devices for Environmental Protection! Future Challenges! Appendices
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Future Challenges
!Key challenge: sustainable business models!What happens when the subsidies disappear?!True cost awareness of conventional sources required
!e.g. typical kW·h prices do not account for future CO2 mitigation!Smaller companies can tend to “re-invent the wheel”
!Particularly prevalent with wave energy concepts
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Future Challenges
!Key challenge: meeting the demand for Nd-Fe-B!New wind turbines will need tonnes of Nd-Fe-B!Also needed for emerging water-based devices!Potential competition with motors for electric vehicles!Major concerns over supply from China
!Significant threat - domestic Chinese consumption!Will new sources be online in time?
!Clear need for better ways to recycle Nd-Fe-B magnets!Some manufacturers now looking at superconductors
!Price of high temp superconducting materials dropping!Price of Nd-Fe-B rising!Concerns of further risk exposure via geopolitics
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Thank You!
For further information:
Gareth P. Hatch, Ph.D.Director of Technology
Dexter Magnetic Technologies, Inc.1050 Morse Avenue
Elk Grove Village, IL 60007USA
Tel: +1-847-956-1140Fax: +1-847-956-8205
Email: [email protected]: http://www.dextermag.com
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Outline
! Introduction! The Challenge of Global Energy Usage! Renewable Energy Resources & Devices
! Wind! Hydro! Ocean! Solar
! PM Devices for Environmental Protection! Future Challenges! Appendices
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Appendix A: Units of Measurement
!A refresher on magnitudes
ISO prefix Order of magnitudekilo- (k) 103
mega- (M) 106
giga- (G) 109
tera- (T) 1012
peta-(P) 1015
exa- (E) 1018
zetta- (Z) 1021
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Appendix A: Units of Measurement
!Energy
Name Symbol Relationjoule J = 1.00 J
foot-pound ft·lb ! 1.36 JBritish thermal unit BTU ! 1.05 kJ
kilocalorie kcal ! 4.19 kJkilowatt-hour kW·h = 3.60 MJ
1 barrel oil equivalent boe ! 6.12 GJ1 tonne oil equivalent toe ! 41.85 GJ
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Appendix A: Units of Measurement
!Power
Name Symbol Relationwatt W = 1 J·s-1
megawatt-hour / year MW·h/yr ! 114.12 Whorsepower hp ! 745.70 W
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Appendix B: A Solar Thought Experiment
!Solar energy!How many PV cells needed for entire global demand?
!Current requirement of 15 TW!Sunniest regions receive mean insolation of 250 W/m2
!Assume solar cell efficiency of 10%!Results in total area of 600,000 km2
!Or, to put it another way...
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Appendix B: A Solar Thought Experiment
After Lewis [2002]. Image Source: Smalley [2004]
6 PV Cell Farms, each 200 miles x 200 miles!