Energy Storage, The
Key Enabler for the
Future Smarter Grid
Dale Bradshaw
CEO Electrivation
dtbradshaw@electrivation.com
423-238-4052
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Why is Energy Storage Critical to
Improving Affordability and
Reliability
Shift wind and solar to meet the peak and make wind
and solar dispatchable.
Provide demand reduction or avoid need for new
capacity
Buy low cost electricity at night and run during high cost
daily peaks
Provide for fast (<4 cycle) backup power for hours to
improve system reliability
Delay or avoid the need to build new transmission or
distribution lines in high cost areas
Provide frequency regulation and spinning reserve
Reduce carbon emissions
Reduce consumption of oil and natural gas
Month
Typical Wind Farm Output
Pattern
Hour
Battery Energy Storage Systems
History Review
Golden Valley Electric Association
NiCad – 27 MW BESS for 15
minutes for reliability
improvement (3 to 82 outages
covered each year)
Advanced Battery
Breakthroughs
• Long Life (defined by number of charge and discharge
cycles is needed)
– Cycle lifetime of 5,000 to 10,000 cycle is now possible
– Charging and discharging daily implies 300 or more
cycles a year, 9,000 cycles in 30 years
• Costs have decreased by 30% to 50%
– $2,000/kW now for 7 hours of storage instead of
$3,500/kW
• Large battery complexes are being built in >1 Mw sizes
• Acceptable efficiency of 70% or more
Lithium Ion (Li-ion) Battery
Attributes
Attribute
Rating
AltairNano Li Ti 1 MW for 15
minutes at 750 to 1050 V
Capital cost
Poor - $800/kW-hr to
$3,000/kW-hr
Round trip efficiency
Excellent – 90 to 95%
Lifetime in Cycle Life
Excellent (7,000 to
16,000 DOD cycles and
28,000 to 250,000 partial
discharge cycles )
Vanadium Redox Battery (VRB)
Attributes-Prudent Energy
Attribute
Rating
Capital cost
Fair - $500/kW-hr to
$800/kW-hr
Round trip efficiency
Fair – 70 to 75%
Lifetime in Cycle Life
Excellent (10,000
cycles?)
NAS battery Attributes and Ratings
S&C Electric and NGK
Attribute
Rating
Capital cost
Fair - $400/kW-hr to
$500/kW-h
Round trip efficiency
Good–80% to 90%
Lifetime in Cycle Life
Good (4,000 to 5,000
cycles)
Sodium Sulfur (NAS) Construction
Cells
Modules
ZnBr Battery Attributes
Premium Power Corporation & ZBB
Attribute
Rating
Capital cost
Excellent - $250/kW-hr
Round trip efficiency
Fair–70% to 75%
Lifetime in Cycle Life
Excellent (>10,000 cycles)
Basic Zinc-Flow Technology (Plating
and de-plating of Zinc)
Zinc-Flow Battery Tower
Module
Premium Power Corporation TransFlow 2050-7
Zinc Bromide battery on a trailer 500 kW, 7.4 hours and
3.8 MW-Hr & ~$1 million
Why Interest in the Premium Power
Corporation Zinc Bromide Battery?
• Lifetime of more than 10,000 cycles of deep charge and
discharge
• Lowest cost battery of all the advanced options based on
CRN due diligence report
• Potentially very low environmental impacts
• PPC ZnBr is UL, FCC, and NFPA certified
• PPC has recently completed the production of its first
TransFlow 2050-5 (500 kW, 2.8 MWh, 5.6 hours)
• PPC has production capacity to meet the needs of the
participating co-ops in this proposal.
• The PPC ZnBr batteries are made in the U.S.
• PPC is well capitalized.
• PPC ZnBr has the potential for fast frequency regulation and
nearly unlimited cycle life.
NRECA CRN projects
• Confirmed addition of a TF-2050-7 for Kotzebue
Electric Association (KEA) in Kotzebue Alaska to
provide:
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Time shift wind to daily peak
Frequency regulation and spinning reserve
Arbitrage
Reduce diesel generator start-ups and O&M
Emergency back-up
Blackstart
Improved fossil plant efficiency
• Other possible future projects in Kauai, South
Carolina, and Floriday
Possible Value Streams for Energy Storage
(Potential Net Present Values)
• Capacity credit or demand charge reduction ($500/kW to
$2500/kW)
• Arbitrage value (Buy low and sell high ranging from $900/kW
to $1500/kW)
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Firming and Shifting Renewables (wind and solar)
Improved thermal plant efficiency
Reduce CO2 emissions from thermal plants
Improve Thermal Plant Reliability
• T&D capital asset deferral ($200/kW to $1300/kW)
– Avoid or delay need for second transformer or transformer bank
– Reduced congestion and line losses
• Frequency regulation ($1600/kW to $4000/kW)
• Dynamic VAr Support ($100/kW)
• Improved service reliability
Range of Values for 6 hours of Energy Storage assuming 2% real discount rate
low gas of $3/MBtu, wind energy off-peak, 70% gas on peak, etc.
Value for 6 hour Energy Storage
Pre se nt Value
(2%)
$8,000
$7,000
$6,000
$5,000
$4,000
Improved off peak
efficiency
Frequency Regulation
Avoided T&D credit
$3,000
$2,000
$1,000
$-
ZnBr price for
7.4 hours is
about $2500/kW
installed
Capacity credit
low
expected
high
Range of Assumptions
Arbitrage value
Future Trends with Advanced Batteries
• Costs in $/kW-hr will drop (mass production) as the value for
installing batteries will increase (increased costs for natural
gas and oil, for carbon emissions, new capacity, etc.)
• Commercial feasibility of advanced batteries will be
established in 2010 with large orders possible by 2011
• Example of expansion (PPC ZnBr batteries):
– 100 MW-hr capacity in 2008
– 400 MW-hr capacity in 2009
– 1500 MW-hr to 4000 MW-hr in 2010
• G&T’s with distribution coops should examine/evaluate
where application of advanced batteries can add value and
reduce cost of electricity and rates.
• Advanced batteries compete with CAES when natural gas
price exceeds $8/MBtu with CAES at $1,000/kW or $3/MBtu
at $2,000/kW assuming no carbon tax. Currently significant
uncertainty in CAES capital cost and natural gas prices
Residential Scale via RedFlow’s
ZnBr at 5 and 10 kW