Your SlideShare is downloading. ×
0
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Arpa e grid-scale energy storage workshop summary - 20091004 - arpa-e

1,276

Published on

Overview of different energy storage technologies

Overview of different energy storage technologies

Published in: Technology, Business
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
1,276
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
27
Comments
0
Likes
1
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. ARPA-E Grid-Scale Energy Storage Workshop Summary October 4, 2009 Seattle Renaissance Hotel Seattle, Washington1
  • 2. Defining the need for storage Possible storage solutions Energy Storage Technologies Key Findings Summary2
  • 3. Energy Storage is required to confer reliability to renewable energy sources and to produce power when the load occurs Texas Panhandle Example Wind generation does not … but shaped wind with correlate well with load… storage is a significant asset. Predictable load, with a Erratic wind 450 regular weekly pattern 4,000 450 Some of the deliveries are 4,000 shaped to meet intermediate 400 and peaking needs 400 3,500 3,500 Energy Delivery (MW) Energy Delivery (MW) 350 350 3,000 3,000 Load (MW) Load (MW) 300 300 Wind often 2,500 2,500 250 spiking during 250 off-peak 2,000 2,000 200 periods 200 1,500 1,500 150 150 1,000 1,000 100 100 Wind lows during 50 on-peak periods 500 50 A portion of deliveries are “baseloaded” 500 to meet round the clock needs 0 0 0 0 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Day Day Load Modeled Wind Energy Production Load Hybrid Storage and Wind Energy Production Notes: 400 MW of wind in Texas Panhandle modeled in conjunction w / local storage facility. Grid storage parameters – 400 MW of capacity Source: Ridge Energy Storage.3
  • 4. Depending on the technology and application, energy storage can provide a wide variety of benefits Supply Delivery Renewables Integration T&D Network Investment Deferral Use of storage to provide capacity value, predictable Use of storage to defer the need for new transmission or scheduling, and time shifting of intermittent renewable distribution capacity to meet demand growth or power systems generation, along with ancillary service requirements requirements Rate Optimization T&D Component Life Extension Use by customers to reduce demand charges and on Use of storage to reduce maximum loading on the grid segments, peak energy charges thereby extending the life of T&D assets Price Arbitrage / Peak Shaving Transmission Access / Congestion Charge Management Purchase of cheap energy for charging (off peak), and Use of storage to avoid congestion charges when demand for discharging to sell at high prices (on peak) transmission service is high Capacity Value T&D Asset Utilization Use of storage in place of traditional generation to meet Improve capital returns on capital investment in T&D investments capacity reserve requirements by increasing capacity utilization of T&D resources via storage Cycling Cost Management Reliability Provide a sink for off-peak power to reduce need to cycle Use of storage to provide ride-through power or to provide time for mid-merit generation, avoiding startup fuel costs and an orderly shut down in the case of an unexpected power outage significant wear and tear on the turbines Ancillary Services Power Quality Use of storage to provide spinning reserve, load Use of energy storage to condition power to reduce voltage following, regulation, black start, etc. variations, reduce frequency variations, maintain power factor, and manage harmonics4
  • 5. Our workshop concerns two broad categories of grid scale energy storage and how to advance related technologies US Electric Capacity (GW) Energy Storage Benefits d GW  Enabling renewable penetration 1,200 Capacity CAGR 2.3%  Reduction of Generation and 1,000 Delivery Inefficiencies 800 ‘07 PHS &  Distributed Generation 600 CAES: 2%  Demand/Peak Load Management 400 Storage Capacity CAGR 0.3% of total  T&D Asset Optimization 200 0  Ensuring a Robust/Reliable Grid 96 97 98 99 0 01 02 03 04 05 06 07  Electricity Arbitrage Storage Description Performance Metrics Technology Examples Applications  Discharge Time  Pumped Hydro Storage The strategy of adjusting and optimizing energy  System Power Rating  CAES Energy generation including reducing the large fluctuations  Round Trip Efficiency  Bulk Electrochemical Storage Management that occur in electricity demand by storing excess  Capital Cost  Advanced Batteries (hours/ diurnal)) electricity during periods of low demand for use  Cycle and Calendar Life  Chemical Storage during periods of high demand.  Site Availability  Response Time  Bulk Electrochemical Storage Power Faults, dynamic operations, or nonlinear loads  System Power Rating  Advanced Batteries Applications often cause various types of power quality  Round Trip Efficiency  Flywheels (seconds/ disturbances such as voltage sags, voltage swells,  Capital Cost  Ultracapacitors minutes)) impulses, notches, flickers, harmonics, etc.  Cycle and Calendar Life  SMES Where can ARPA-E Where can ARPA-E make the greatest make the greatest5 Source: DOE Electric Power Annual 2007, Energy Storage impact? impact? Association, BAH Analysis
  • 6. Defining the need for storage Possible storage solutions Energy Storage Technologies Key Findings Summary6
  • 7. Workshop participants from utilities believed that storage is headed toward wide utilization from generation points to individual homes “Residental generation “Residental generation from renewables has from renewables has doubled every year for doubled every year for the last decade”. the last decade”. A. Nourai - -AEP A. Nourai AEP … each technology has technical challenges, and room for7 development within ARPA-E. Source: A. Nourai, American Electrical Power, Inc. presentation at EESAT 2009, October 4-7, 2009
  • 8. Grid storage will by supplied by a combination of technologies with Varied power and energy storage capacities • Ni-Cd: Nickel-Cadmium • CAES: Compressed Air Energy Storage • Ni-MH: Nickel-Metal Hydride • EDLC: Double Layer Capacitors • L/A: Lead Acid • PSH: Pumped Hydro • Li-Ion: Lithium Ion • Vanadium Redox • Na-S: Sodium Sulfur • ZnBr: Zinc-Bromine8 Source: Brad Roberts, ESA website, May 2009.
  • 9. Requirements for Grid Scale Energy Storage are becoming more clear and fall into three categories, according to our participants Power Outputs at Different Points on the Grid 10-100 MW Units 1-10 MW Units 100-1000 MW Units (such as NaS) (such as pumped hydro) (for Community Storage)9 Source: A. Nourai, American Electrical Power, Inc., presentation to EESAT, October 4-7, 2009.
  • 10. Grid storage will by supplied by a combination of technologies at varied stages of development Grid Storage Stages of Maturity by Technology Laboratory Stage Prototype Stage Mature Technology Flywheels NiCd Li-Ion Ni-MH Ultracapacitors Na S Hydro Lead Acid / Lead Carbon Flow Batteries Advanced CAES CAES The participants would like to see ARPA-E catapult more of these technologies to maturity, in order to: 1) Increase functionality of renewables 2) Reduce the need for spinning reserves and thereby 3) Cut greenhouse gasses and 4) Reduce the use of fossil fuels10
  • 11. Workshop participants agreed that ARPA-E and the DOE Office of Electricity have a complementary roles in technology development Office of Electricity Office of ARPA-E Future Programs Delivery and Energy Science and Private Venture Capital Reliability Prototype/   Demos Tech Gap ARPA-E Chief Commercialization Transition Area Gaps • ARPA-E should develop alpha-prototype level stage, • OE should then develop alpha-prototypes to a final stage • ARPA-E should focus on Valley of Death between laboratory models and alpha prototype11 11
  • 12. Defining the need for storage Possible storage solutions Energy Storage Technologies Key Findings Summary12
  • 13. Pumped Storage Hydro is the most popular form of grid scale energy management, but offers little potential for innovation Pumped Storage Hydro (PSH) Technical Overview Technology Highlights Technology Highlights Description Description PSH uses off peak power to pump water from a reservoir to a higher PSH uses off peak power to pump water from a reservoir to a higher •• The pumping process makes the plant a net consumer of The pumping process makes the plant a net consumer of elevation; during periods of high electrical demand, the stored water elevation; during periods of high electrical demand, the stored water energy overall, but pumped storage is the largest-capacity form energy overall, but pumped storage is the largest-capacity form is released through turbines to create electricity is released through turbines to create electricity of grid energy storage commercially available of grid energy storage commercially available PSH is technologically mature and reliable compared to other PSH is technologically mature and reliable compared to other •• Within the US, there are 38 facilities with 22 GW of power Within the US, there are 38 facilities with 22 GW of power storage options storage options capacity capacity •• These power plants are still used to provide ancillary services These power plants are still used to provide ancillary services (such as helping manage grid frequency and providing clean (such as helping manage grid frequency and providing clean reserve generation) reserve generation) •• The number of environmentally acceptable sites for future The number of environmentally acceptable sites for future pumped hydroelectric facilities is very limited due to the need pumped hydroelectric facilities is very limited due to the need for significant elevation changes in pumped hydroelectric plan for significant elevation changes in pumped hydroelectric plan designs designs •• Pumped storage can be constructed at capacities of 100-1000 Pumped storage can be constructed at capacities of 100-1000 of MW and discharge from 4-10 hours with cost in the range of of MW and discharge from 4-10 hours with cost in the range of $2200 -- $2250/KW $2200 $2250/KW Technology Maturity Key Players Key Players •• Pumped storage plants are in wide use globally Pumped storage plants are in wide use globally R&D Pilot-scale Commercial •• Largest pumped hydro facility globally is in Bath County, Largest pumped hydro facility globally is in Bath County, Bench-scale Demonstration Virginia Virginia13 Source: DOE, EPRI, ESA.
  • 14. CAES has demonstrated operational improvements in NG plants and potential with renewables, but siting is limiting Compressed Air Energy System (CAES) Technical Overview Technology Highlights Technology Highlights Description Description In CAES systems, electricity is used to compress air during off-peak In CAES systems, electricity is used to compress air during off-peak •• A CAES plant with underground storage must be built near a A CAES plant with underground storage must be built near a hours hours favorable geological formation favorable geological formation The compressed air is most economically stored underground in salt The compressed air is most economically stored underground in salt •• Cost of the underground cavern is a significant contributor to Cost of the underground cavern is a significant contributor to caverns, hard rock caverns, or porous rock formations caverns, hard rock caverns, or porous rock formations cost cost •• Above ground compressed air storage in gas pipes or pressure Above ground compressed air storage in gas pipes or pressure vessels is practical and cost effective for storage plants with vessels is practical and cost effective for storage plants with less than about 100 MWh of storage less than about 100 MWh of storage •• Compressed air stored in underground caverns released to Compressed air stored in underground caverns released to power the compression cycle of the gas turbine generator power the compression cycle of the gas turbine generator reduces startup time from (20 – 30 minutes to 9 – 11) and also reduces startup time from (20 – 30 minutes to 9 – 11) and also cuts natural gas usage cuts natural gas usage •• Charging Ratio ranges from .82-1.3 (kWh used to store/kWh Charging Ratio ranges from .82-1.3 (kWh used to store/kWh discharge) discharge) •• Newer systems under investigation currently will generate Newer systems under investigation currently will generate power by air discharge, without natural gas as a required co- power by air discharge, without natural gas as a required co- generation carburant. generation carburant. Technology Maturity Key Players Key Players •• Alabama Electric Cooperative Inc (McIntosh, AL) Alabama Electric Cooperative Inc (McIntosh, AL) R&D Pilot-scale Commercial Bench-scale Demonstration14 Source: DOE, Press Releases.
  • 15. VRB has enormous performance potential at scale but a reduction in system cost is required for deployment Vanadium Redox Flow Battery (VRB) Technical Overview Technology Highlights Technology Highlights Description Description The VRB exploits the ability of vanadium to exist in solution in 4 The VRB exploits the ability of vanadium to exist in solution in 4 •• Two aqueous electrolytes with active vanadium species in Two aqueous electrolytes with active vanadium species in different oxidation states; it thus uses only one electroactive different oxidation states; it thus uses only one electroactive different oxidation states pumped through reaction cell halves different oxidation states pumped through reaction cell halves element, preventing cross contamination by diffusion of ions across element, preventing cross contamination by diffusion of ions across •• At negative electrode, V3+ is converted to V2+ during battery the membrane At negative electrode, V3+ is converted to V2+ during battery the membrane charging; during discharge, V2+ ions are reconverted back to charging; during discharge, V2+ ions are reconverted back to Also, as a flow battery, VRB’s capacity in only limited by the size of Also, as a flow battery, VRB’s capacity in only limited by the size of V3+; at the positive electrode, similar reaction occurs between V3+; at the positive electrode, similar reaction occurs between the storage tanks the storage tanks ionic forms V5+ and V4+ ionic forms V5+ and V4+ •• Electrolyte stored externally, allowing independent power and Electrolyte stored externally, allowing independent power and energy ratings: energy determined by electrolyte stored energy ratings: energy determined by electrolyte stored externally; power determined by size and number of electrodes externally; power determined by size and number of electrodes in cell stack in cell stack •• Efficiency ~70% Efficiency ~70% •• Cost: ~$500/kWh, with cost at $150/kWh possible for 8-hour Cost: ~$500/kWh, with cost at $150/kWh possible for 8-hour storage systems (due to scale up); installation costs currently at storage systems (due to scale up); installation costs currently at $2500/kW; mass market costs are projected at $720/kW and $2500/kW; mass market costs are projected at $720/kW and $144/kWh $144/kWh •• Cost of electrolytes for scale up is more than double that for Cost of electrolytes for scale up is more than double that for zinc-bromine (another notable flow battery type), but system is zinc-bromine (another notable flow battery type), but system is more scalable more scalable •• Capacity: 275 kW – 3 MW Capacity: 275 kW – 3 MW •• Lifetime: 10-20 years Lifetime: 10-20 years •• Projected doubling of energy density possible (through better Projected doubling of energy density possible (through better VRB Schematic absoption of active materials by electrolyte), up from 25 Wh/kg absoption of active materials by electrolyte), up from 25 Wh/kg Technology Maturity Key Players Key Players •• Current DOE Demo Project: SMUD/Sprint 20 kW in Sacramento Current DOE Demo Project: SMUD/Sprint 20 kW in Sacramento •• Prudent Energy (China) -- recently acquired VRB, which had earlier acquired other VRB Prudent Energy (China) recently acquired VRB, which had earlier acquired other VRB R&D Pilot-scale Commercial patent holders (such as a Sumitomo division and Pinnacle) patent holders (such as a Sumitomo division and Pinnacle) Bench-scale Demonstration •• GEFC (China) – focus areas include membrane, electrode, electrolyte and stack GEFC (China) – focus areas include membrane, electrode, electrolyte and stack •• University of New South Wales University of New South Wales15 Source: DOE, EPRI, Press Releases.
  • 16. Zn-Br batteries have moderate energy density, good power density, better cycling performance and poor scalability Zinc - Bromine Flow Battery Technical Overview Technology Highlights Technology Highlights Description Description A solution of zinc bromide is stored in 2 tanks (one tank stores A solution of zinc bromide is stored in 2 tanks (one tank stores •• Construction similar to other Flow batteries, however, rather Construction similar to other Flow batteries, however, rather electrolyte for positive electrode reactions and the other for the electrolyte for positive electrode reactions and the other for the than all active materials being dissolved in the electrolyte, than all active materials being dissolved in the electrolyte, negative) negative) during charge, zinc is electroplated on the anode and bromine during charge, zinc is electroplated on the anode and bromine is evolved at the cathode is evolved at the cathode Zn-Br battery capacity is less scalable than VRB flow batteries since Zn-Br battery capacity is less scalable than VRB flow batteries since •• On discharge, the bromine is returned to the battery stacks, On discharge, the bromine is returned to the battery stacks, it is not a pure flow battery it is not a pure flow battery and zinc is oxidized to zinc ions on the anodes, bromine is and zinc is oxidized to zinc ions on the anodes, bromine is reduced to bromide ions on the cathodes reduced to bromide ions on the cathodes •• Efficiency: 65-75% Efficiency: 65-75% •• Cost: initial system cost comparable to VRB; electrolytes for Cost: initial system cost comparable to VRB; electrolytes for scale up is much cheaper, but system less scalable; mass scale up is much cheaper, but system less scalable; mass market costs projected at $ 720 kW and 144 // kWh market costs projected at $ 720 kW and 144 kWh •• Capacity, Power Ratings: <1 MW, 0.01 – 5 MWh Capacity, Power Ratings: <1 MW, 0.01 – 5 MWh •• Lifetime: 5-10 years Lifetime: 5-10 years •• Safety enhanced (by polybromide formation during Safety enhanced (by polybromide formation during compounding) compounding) Zinc-Bromine Flow Battery Schematic Technology Maturity Key Players Key Players •• DOE funding 1MWh Demo project in California (2 -- 500 kWh DOE funding 1MWh Demo project in California (2 500 kWh installations) installations) R&D Pilot-scale Commercial •• ZBB Energy Corp. ZBB Energy Corp. Bench-scale Demonstration •• Premium Power Corporation Premium Power Corporation16 Source: DOE, Energy Storage Association.
  • 17. L/A Batteries have a low production cost but present cycling, weight, toxicity and depth of discharge problems Lead Acid (L/A) Battery Technical Overview Technology Highlights Technology Highlights Description Description L/A battery has low relative cost and is a popular choice for power L/A battery has low relative cost and is a popular choice for power •• Lead-acid is one of the oldest and most developed battery Lead-acid is one of the oldest and most developed battery quality and uninterrupted power supply application but it is limited quality and uninterrupted power supply application but it is limited technologies technologies due to its short cycle life due to its short cycle life •• Several commercial, large-scale energy management Several commercial, large-scale energy management applicatoins have been installed (California, Hawaii, Puerto applicatoins have been installed (California, Hawaii, Puerto Rico, and Germany) Rico, and Germany) •• Demonstrated rated energy ranges from 4.5 to 40 MWh Demonstrated rated energy ranges from 4.5 to 40 MWh •• Demonstrated rated power ranges from 3 to 10 MW; however, Demonstrated rated power ranges from 3 to 10 MW; however, amount of energy (kWh or MWh) the battery can deliver is not amount of energy (kWh or MWh) the battery can deliver is not fixed and depends on rate of discharge fixed and depends on rate of discharge •• Cost: installed cost ($/kw) have ranged from $239 to $805 Cost: installed cost ($/kw) have ranged from $239 to $805 (1995 dollars); cost // kWh have ranged from $201 to $707 (1995 dollars); cost kWh have ranged from $201 to $707 •• Innovative Lead Carbon batteries under development currently Innovative Lead Carbon batteries under development currently may make this system more attractive for Grid Storage may make this system more attractive for Grid Storage applications applications An islanded lead acid battery stack in Alaska Technology Maturity Key Players Key Players •• GNB Industrial Power/Exide, Delco, East Penn, Teledyne, Optima GNB Industrial Power/Exide, Delco, East Penn, Teledyne, Optima R&D Pilot-scale Commercial Batteries, JCI Battery Group, Crown Battery, Wildcat, Batteries, JCI Battery Group, Crown Battery, Wildcat, Caterpillar/Firefly Energy. Caterpillar/Firefly Energy. Bench-scale Demonstration17 Source: Energy Storage Association.
  • 18. Na-S batteries are promising for grid-storage, but high operating temperatures (300 to 350 °C) limits its use Sodium Sulfur Battery (Na-S) Technical Overview Technology Highlights Technology Highlights Description Description A Na-S battery has high energy density, high efficiency, and long A Na-S battery has high energy density, high efficiency, and long •• Cylindrical tube composed of negative electrode of liquid Cylindrical tube composed of negative electrode of liquid cycle life, and is fabricated from inexpensive materials cycle life, and is fabricated from inexpensive materials sodium in the inner core; positive electrode comprised of a sodium in the inner core; positive electrode comprised of a surrounding layer of sulfur; Beta-Alumina Solid Electrolyte surrounding layer of sulfur; Beta-Alumina Solid Electrolyte (BASE) layer separates the electrodes; BASE electrolyte is a (BASE) layer separates the electrodes; BASE electrolyte is a good conductor of sodium ions, but a poor conductor of ions, good conductor of sodium ions, but a poor conductor of ions, thereby preventing self-discharge thereby preventing self-discharge •• During discharge: molten sodium serves as anode; positive During discharge: molten sodium serves as anode; positive sodium ion passes through the BASE (electrolyte) to the sulfur sodium ion passes through the BASE (electrolyte) to the sulfur layer to form sodium polysulfide; the sodium level in the inner layer to form sodium polysulfide; the sodium level in the inner core drops core drops •• During charging: sodium polysulfides release the positive During charging: sodium polysulfides release the positive sodium ions back through the electrolyte to recombine as sodium ions back through the electrolyte to recombine as elemental sodium elemental sodium •• Once running, heat produced by charging and discharging Once running, heat produced by charging and discharging cycles maintains sufficient operating temperature with no cycles maintains sufficient operating temperature with no external source, however high temperatures of up to 350° C external source, however high temperatures of up to 350° C are needed initially are needed initially •• Efficiency ~89-92%; Lifetime up to 15 years Efficiency ~89-92%; Lifetime up to 15 years •• Capacity // Power: from 50 kW // 400 kWh to 8MW // 64MWh Capacity Power: from 50 kW 400 kWh to 8MW 64MWh •• ESA claims in Japan there are > 190 sites totaling 270 MW ESA claims in Japan there are > 190 sites totaling 270 MW Technology Maturity Key Players Key Players •• DOE funded Demo Project: Pacific Gas & Electric Sodium Sulfur Battery (allows substation DOE funded Demo Project: Pacific Gas & Electric Sodium Sulfur Battery (allows substation upgrade deferment). Project on hold upgrade deferment). Project on hold R&D Pilot-scale Commercial •• DOE funded Demo Project: a 1 MW, 7.2 MWh, NaS BESS at a major Long Island Bus depot facility DOE funded Demo Project: a 1 MW, 7.2 MWh, NaS BESS at a major Long Island Bus depot facility (shifts a compressor peak load to off-peak capacity and provides emergency backup power); uses (shifts a compressor peak load to off-peak capacity and provides emergency backup power); uses Bench-scale Demonstration NAS™ Battery (developed jointly by NGK and Tokyo Elec. Power) NAS™ Battery (developed jointly by NGK and Tokyo Elec. Power)18 Source: DOE, EPRI, Energy Storage Association, Press Releases.
  • 19. Metal Air battery’s energy density and shelf life has garnered attention but poor recharge capability limits use currently Metal Air Battery Technical Overview Technology Highlights Technology Highlights Description Description In metal air batteries, the reactive anode and air electrode result in In metal air batteries, the reactive anode and air electrode result in •• The anodes in these batteries are commonly available metals The anodes in these batteries are commonly available metals an inexhaustible cathode reactant an inexhaustible cathode reactant with high energy density that release electrons when oxidized; with high energy density that release electrons when oxidized; This battery is potentially the most compact and, potentially, the This battery is potentially the most compact and, potentially, the anode candidates include zinc for larger battery ranges (Other anode candidates include zinc for larger battery ranges (Other least expensive battery, but recharging remains difficult and least expensive battery, but recharging remains difficult and metals such as lithium, calcium, magnesium, aluminum, or iron metals such as lithium, calcium, magnesium, aluminum, or iron inefficient inefficient may be used but are not as commercially developed as zinc) may be used but are not as commercially developed as zinc) •• The cathodes (or air electrodes) are often made of a porous The cathodes (or air electrodes) are often made of a porous carbon structure or a metal mesh covered with proper catalysts; carbon structure or a metal mesh covered with proper catalysts; there is essentially no weight associated with the cathode there is essentially no weight associated with the cathode reactant, other than the air electrode, since the cathode reactant, other than the air electrode, since the cathode reactant is oxygen from air reactant is oxygen from air •• The electrolytes are often a good OH- ion conductor such as The electrolytes are often a good OH- ion conductor such as KOH; electrolyte may be in liquid form or a solid polymer KOH; electrolyte may be in liquid form or a solid polymer membrane saturated with KOH membrane saturated with KOH •• Not yet technically viable for grid-storage: Not yet technically viable for grid-storage: – Electrical recharging very difficult and inefficient; many – Electrical recharging very difficult and inefficient; many manufacturers offer refuelable units where the consumed manufacturers offer refuelable units where the consumed metal is mechanically replaced and processed separately metal is mechanically replaced and processed separately – Rechargeable metal air batteries that are under – Rechargeable metal air batteries that are under development have a life of only a few hundred cycles and development have a life of only a few hundred cycles and an efficiency about 50% an efficiency about 50% Metal Air Schematic •• Zinc-Air systems are potentially rechargeable Zinc-Air systems are potentially rechargeable Technology Maturity Key Players Key Players •• EVionyx, AER Energy Resources, Metallic Power, Chem Tek, EVionyx, AER Energy Resources, Metallic Power, Chem Tek, R&D Pilot-scale Commercial Power Zinc, Electric Fuel, Alupower, Aluminum Power, Zoxy Power Zinc, Electric Fuel, Alupower, Aluminum Power, Zoxy Energy Systems, ReVolt Energy Systems, ReVolt Bench-scale Demonstration19 Source: DOE, Energy Storage Association.
  • 20. Flywheels are used in instances when high power density is required for disruptions lasting seconds to minutes Flywheels Technical Overview Technology Highlights Technology Highlights Description Description Flywheels are marketed as environmentally safe, reliable, modular, Flywheels are marketed as environmentally safe, reliable, modular, •• A flywheel is a simple form of mechanical (kinetic) energy A flywheel is a simple form of mechanical (kinetic) energy and high-cycle life alternative for uninterruptible power supplies and and high-cycle life alternative for uninterruptible power supplies and storage; energy is stored by causing a disk or rotor to spin on storage; energy is stored by causing a disk or rotor to spin on other power-conditioning equipment designed to improve the quality its axis; stored energy is proportional to the flywheel’s mass its axis; stored energy is proportional to the flywheel’s mass other power-conditioning equipment designed to improve the quality and the square of its rotational speed of power delivered to critical or protected loads and the square of its rotational speed of power delivered to critical or protected loads •• The energy and power characteristics of a flywheel system are The energy and power characteristics of a flywheel system are more or less independent variables therefore in theory it can be more or less independent variables therefore in theory it can be designed for any power and energy combination; in practice, designed for any power and energy combination; in practice, technical limitations such as rotor strength and weight, and technical limitations such as rotor strength and weight, and resource limitations such as cost limit design characteristics resource limitations such as cost limit design characteristics •• In general, flywheels can be classified as low speed with rpm In general, flywheels can be classified as low speed with rpm measured in thousands or high speed with rpm measured in measured in thousands or high speed with rpm measured in the tens of thousands the tens of thousands – Low-speed flywheels are usually made from steel and – Low-speed flywheels are usually made from steel and designed for high-power output designed for high-power output – High-speed flywheels are typically made from carbon or – High-speed flywheels are typically made from carbon or carbon and fiberglass composite materials that will carbon and fiberglass composite materials that will withstand the higher stresses associated with higher rpm withstand the higher stresses associated with higher rpm •• There are two major avenues of research in flywheel There are two major avenues of research in flywheel technology at present improved passive magnetic bearings, technology at present improved passive magnetic bearings, and improved wheel materials and improved wheel materials •• Primary cost areas are the rotor materials fabrication and motor Primary cost areas are the rotor materials fabrication and motor Cross-Section Of A Flywheel Module generator materials fabrication efficiency generator materials fabrication efficiency (Courtesy NASA Glenn Research Center) Technology Maturity Key Players Key Players •• Lawrence Livermore National Laboratories ;; Pennsylvania Lawrence Livermore National Laboratories Pennsylvania R&D Pilot-scale Commercial State University; University of Texas State University; University of Texas Bench-scale Demonstration •• Beacon Power; Boeing Phantom Works Beacon Power; Boeing Phantom Works20 Source: DOE, EPRI, ESA.
  • 21. Ultracapacitors are an effective way to buffer high power requirements, but still fall short of battery energy levels Ultracapacitors Technical Overview Technology Highlights Technology Highlights Description Description •Ultracapacitors are two series capacitors with an electric double •Ultracapacitors are two series capacitors with an electric double •• Ultracapacitors’ electric double layer (EDL) is formed between Ultracapacitors’ electric double layer (EDL) is formed between layer (EDL) of very high surface area. These systems have layer (EDL) of very high surface area. These systems have each of the electrodes and the electrolyte ion layers. The each of the electrodes and the electrolyte ion layers. The 100,000x energy density over standard capacitors, beginning to 100,000x energy density over standard capacitors, beginning to distance over which the charge separation occurs is just a few distance over which the charge separation occurs is just a few approach lithium ion batteries. Their widespread use is hampered approach lithium ion batteries. Their widespread use is hampered angstroms. The extremely large surface area makes the angstroms. The extremely large surface area makes the by self discharge and cost issues. by self discharge and cost issues. capacitance and energy density of these devices thousands of capacitance and energy density of these devices thousands of times larger than those of conventional electrolytic capacitors times larger than those of conventional electrolytic capacitors •• The electrodes are often made with porous carbon material. The electrodes are often made with porous carbon material. •• The electrolyte is either aqueous or organic. The electrolyte is either aqueous or organic. •• Aqueous ultracaps have a lower energy density due to a lower Aqueous ultracaps have a lower energy density due to a lower cell voltage, but are less expensive and work in a wider cell voltage, but are less expensive and work in a wider temperature range. temperature range. •• Asymmetrical ultracaps use metal for one of the electrodes Asymmetrical ultracaps use metal for one of the electrodes have a significantly larger energy density than the symmetric have a significantly larger energy density than the symmetric ones do and also have a lower leakage current. ones do and also have a lower leakage current. •• Lower energy density than batteries, but can be cycled Lower energy density than batteries, but can be cycled 100,000x and are much more powerful than batteries (fast 100,000x and are much more powerful than batteries (fast charge and discharge capability). charge and discharge capability). •• Have been used for wind turbine blade-pitch control devices to Have been used for wind turbine blade-pitch control devices to control the rate at which power increases and decreases with control the rate at which power increases and decreases with changes in wind velocity. changes in wind velocity. Ultracapacitor Overview Schematic Technology Maturity Key Players Key Players •• Maxwell, Kwanwa. Maxwell, Kwanwa. R&D Pilot-scale Commercial Bench-scale Demonstration21 Source: ESA.
  • 22. SMES is utilized to enhance power quality in a few areas, but do not see widespread use due to cost Superconducting Magnetic Energy Storage (SMES) Technical Overview Technology Highlights Technology Highlights Description Description SMES offer efficient energy storage with 5% loss, since there are SMES offer efficient energy storage with 5% loss, since there are •• SMES systems store energy in the magnetic field created by SMES systems store energy in the magnetic field created by none of the inherent losses associated with energy conversion none of the inherent losses associated with energy conversion the flow of direct current in a superconducting coil which has the flow of direct current in a superconducting coil which has Power is available almost instantaneously, and very high power Power is available almost instantaneously, and very high power been cryogenically cooled to a temperature below its been cryogenically cooled to a temperature below its output is provided for a brief period of time output is provided for a brief period of time superconducting critical temperature. SMES system include: superconducting critical temperature. SMES system include: – Superconducting coil, all practical SMES systems – Superconducting coil, all practical SMES systems installed to date use a superconducting alloy of niobium installed to date use a superconducting alloy of niobium and titanium (Nb-Ti), which requires operation at and titanium (Nb-Ti), which requires operation at temperatures near the boiling point of liquid helium, about temperatures near the boiling point of liquid helium, about 4.2 K (-269°C or -452°F) – 4.2 centigrade degrees above 4.2 K (-269°C or -452°F) – 4.2 centigrade degrees above absolute zero absolute zero – Cryogenic refrigerator to maintain the coil at a – Cryogenic refrigerator to maintain the coil at a temperature sufficiently low to maintain a temperature sufficiently low to maintain a superconducting state in the wires; commercial SMES superconducting state in the wires; commercial SMES today this temperature is about 4.5 K (-269°C) requiring today this temperature is about 4.5 K (-269°C) requiring 200 to 1000 watts of electric power for each watt that 200 to 1000 watts of electric power for each watt that must be removed must be removed – Power conversion system – Power conversion system – Control system, establishes a link between power – Control system, establishes a link between power demands from the grid and power flow to and from the demands from the grid and power flow to and from the SMES coil SMES coil •• The superconductor material is one of the major costs of a The superconductor material is one of the major costs of a superconducting coil and SMES system superconducting coil and SMES system SMES schematic Technology Maturity Key Players Key Players •• American Superconductor American Superconductor R&D Pilot-scale Commercial Bench-scale Demonstration22 Source: DOE, EPRI, ESA.
  • 23. Defining the need for storage Possible storage solutions Energy Storage Technologies Key Findings Summary23
  • 24. Our first breakout sessions was devoted to large-scale energy management technologies • Compressed Air Energy Storage (CAES) – Chair: Georgianne Peek, Sandia • Bulk Electrochemical Storage: Liquid metal/flow batteries/metal air) – Chair: John Boyes, Sandia • Advanced Batteries: Advanced Li-ion/NiCd/Pb-Acid/beyond Li-Ion) – Chair: Ali Nourai, AEP • Other Bulk Storage Approaches: Underground Pumped Hydro/Chemical Storage – Chair: Klaus Lackner, Columbia University • Power Conditioning Systems and Balance of Plant – Chair: Brad Roberts, ESA24
  • 25. Whereas our second round of breakout sessions focused on high power applications necessary for seconds-to-minutes management • Bulk Electrochemical Storage: Liquid metal/flow batteries/metal air) Chair: Ali Nourai, AEP • Advanced Batteries: Advanced Li-ion/NiCd/Pb-Acid/beyond Li-Ion) – Chair: John Boyes, Sandia • Ultracapacitors/SMES – Chair: Dan Rastler, EPRI • Flywheels and Other Power Focused Storage Applications – Chair: Haresh Kamath, EPRI25
  • 26. Each breakout session was asked to answer a list of questions about their candidate technologies for discussion with the group Key questions for each technology breakout session: • Highest ARPA-E mission impact storage applications and why – Reduction of energy-related emissions, including greenhouse gases – Improvements in efficiency of power generation and delivery – U.S. technological lead • Required performance and cost for significant deployment in these applications vs state of the art • Key technical and cost barriers/challenges • Promising emerging technology opportunities/approaches to overcome barriers • “Holy grails”/grand challenges that if solved would be game changers • Existing funding gaps (government, private investors, corporate R&D) – Development stage gaps, Technology funding gaps • Ideal roles of ARPA-E vs Office of Electricity @ DOE • Level of development required for private sector hand-off • Required levels of funding for meaningful progress – Proof of Concept – Meaningful prototype (scale?) – Meaningful small-scale demonstration26
  • 27. Workshop participants agreed on the general cost and performance metrics for any future ARPA-E Grid Storage Programs General Metrics to Evaluate Grid Scale Energy Storage Projects • Performance Metrics – Multi-hour storage for energy, seconds to minutes for power – High cycle efficiency, – Peak power capability, – Cycle life, – Calendar life, – Operation at temperature ext. • Cost Metrics – $/kWh cycled (over lifetime) – $/kW*h, capital cost – Total lifecycle cost • How to measure R&D program successes – Include market pull as requirement in proposals – Build national utility scale testbed- badly needed – Understand storage reduction of GHG if charged with coal27
  • 28. For new technologies to be adopted however, the members urged consideration of the whole grid storage development landscape Technology Challenges New Storage Industry Risks Cost Metrics Requirements Stakeholders New Drivers – Technical – Capital Costs – Power Quality – Regulators – Climate Bill/Law – Identification of – Construction – Power Storage – RTO/ISO – Executive Risk Levels Costs Time – Environment Order (Calif.) – Mitigation – Operations – Life Cycle – FERC – National Activities – Maintenance – Technical – DOE Security • Prototype – Life Cycle Parameters – Industry – NIST Standards • Fabrication – Schedule – Gov’t/ Industry • Testing Analysis Partnership – Risk Impacts – Cost Sharing – Performance Metrics First-of-a-kind Demonstration Plant – Reliability (FOAK) Storage (Usually administered – Availability Through DOE/OE)28 Energy Storage
  • 29. Many participants concurred with the EPRI goals/opportunities for grid energy storage paradigms Grid Storage Energy System Requirements Flow Li-Ion NaS Pumped CAES Ultra SMES Flywheels Battery Battery Battery Hydro Capacitors •Footprint • Improved • Lower cost • Lower • Machinery- • Develop • Increase • Friction Optimized for Electrolyte of chrome investment Apply nano-carbon Superconduc Reduction, Site plating for costs Higher materials to tor joint durability • Improved increase temperature battery can temperature • New •Double Anode and • Reduced carbon and/or go expansion materials for Energy Cathodes environment surface area reduced Density • Reduce from al impact turbines to • Increase cell friction •Reduce Content of aluminum to CAES (go voltage (from • Flywheel Permitting Cobalt and steel casing from 2100F 2.5 to 3V to tipspeed Issues graphite • Beta to 2500 F) twice that) control • Reduce • Improve Alumina • Above Capital Safety Tube: ground Operating Improve piping •Scale-Up Characteristi and • Demo Maintenance cs surface DR Costs over • Improve CAES 20 years cell seal: Systems • Incorporate ceramic to • Reduce Thermal metal bond cost of Management piping and into design potential • Optimize corrosion of Electrolyte high concentration pressure with pipe Electrode systems surface area29 Source: Daniel Rastler, Market Driven Distributed Energy Storage System Requirements for Load Management Applications, EPRI, 2006.
  • 30. Finally, the group applauded the efforts of the AEP Storage Group for their efforts to define residential storage standards • At current renewable generation growth rates, residential storage is forcasted to see wide deployment within five years • No standards of performance are currently established/accepted by industry, but will be required for broad adoption – Standards development for energy storage should be pursued by DOE AEP Guidelines for Residential Energy Storage Key Parameters Value Power 25 kVA Energy 50kWh Voltage 120/240 V Round Trip Energy Efficiency >85% Target cost parameters are $1000/kW and $500/kWh Similar guidelines are needed in other storage sectors Source: American Electric Power, “Functional Specification for Community Energy Storage (CES)30 Unit.”, available at www.aeptechcenter.com/ces.
  • 31. The participants also described enabling technologies and high-risk concepts that would greatly advance grid scale energy storage • Reliable, inexpensive, rechargable metal-air batteries, • Fuel as electrical storage media • Electrochemical conversion to methanol • Thermal storage cycles • Economically viable Ericsson cycles for storage • Storage system scalability • Organic active materials for flow batteries. • Algae farms growing carbon electrodes • Hybrid supercaps to provide hours of energy • Multiple platforms vehicle + grid A 34-MW, 245-MWh NaS battery installation. • Combine thermal + electrical storage • Integrated renewable production (wind + storage + engine) • Seasonal power storage • Better balance of plant electronics • More focus on Molten Salt Systems31
  • 32. In summary, the workshop revealed enormous unexplored territory across the grid storage energy space… Opportunities in Grid Scale Reasons why project haven’t Energy Storage already been developed • Large Scale Diurnal Storage, • Without significant government especially on the coasts backing and testing, utilities • Rapid increase in delocalized wouldn’t adopt new technologies residential generation will cause • Proposed new storage techniques unmet demand for storage were deemed too risky • The increase to 20% generation • Grid research topics in general have from renewables from many states been ignored for decades will require significant storage to – In 2006, the total Grid Storage maintain grid output quality Budget of EPRI was < $50k • Wind generation providers are nationally! beginning to look at storage • FERC previously financially integration on their sites. disincentivized research by utilities None of these reasons still apply! … and a community of innovators waiting for the right environment to turn ideas into reality. That time is now!32

×