Energy Storage Overview Thomas Johnson Alaska Center for Energy
and Power ACEP (907) 474 1143 www.uaf.edu/acep Alaska Center for
Energy and Power http://www.uaf.edu/acep/ (907) 474 1145
Slide 2
Overview Why? Types of storage ACEP flow battery experiences
Energy storage in Alaska
Slide 3
Why Storage and Why Now? Balance supply and demand Load
leveling Load shifting UPS Uninterruptible Power Supply Potential
to save fuel and $$$
Slide 4
Types of Storage Potential Elevation difference Electrochemical
Super capacitors Chemical Magnetic Mechanical Kinetic Thermal
Slide 5
Fossil Fuel & Biomass
Slide 6
Hydrogen Yes, hydrogen can be used for energy storage In most
applications there are better alternatives
Slide 7
Compressed Gas
Slide 8
Hydroelectric Reservoir storage Energy = mgh Pumped
hydroelectric ~70% efficient Needs the right circumstances
Elevation change
Slide 9
Super Capacitors Battery-like characteristics Extremely rapid
charge and discharge Virtually no degradation High self-discharge
rate Not suitable for long term storage
Slide 10
Flywheels Kinetic energy storage Energy=1/2 mv 2 Changed from
heavy rotors to fast rotors Turn around efficiency up to 85%
Short-term storage Containment?
Slide 11
Batteries Electrochemical storage Can be efficient The
technology is rapidly improving Most types degrade
Slide 12
Other Liquid metal battery Magnetic storage Thermal storage
And
Slide 13
Flow Batteries at ACEP
Slide 14
Vanadium redox batteries VRB and Prudent Energy Turn around
efficiency 65%-75% Very low degradation High self-discharge rate
The stack was reliable The VRB balance of plant was not
Slide 15
Pumps
Slide 16
Leaks
Slide 17
Storage in Alaska Installations throughout the state Various
levels of success Or lack thereof A few examples:
Slide 18
Usibelli Coal Mine Electrically-operated dragline 6 MW draw, 2
MW regeneration, 60 second cycle time Caused grid stability
problems 40 ton, 1000 rpm Flywheel was installed and reduced the
fluctuations from 8MW to.5 MW Installed in 1982 and still in
use
Slide 19
Chena Hot Springs Batteries 1 MW Battery module intended as a
UPS Lead acid chemistry Not suitable for load leveling Never
commissioned
Slide 20
Premium Power Battery 500 kW, 3.4 MWhr Delivered to Kotzebue in
October 2011 Zinc-Bromide chemistry Intended to provide storage
during times of excess wind. Never commissioned Being returned to
the manufacturer
Slide 21
Wales Wind-diesel hybrid system Battery and thermal storage
enabled diesel-off operation System proved it could work For a
variety of reasons, the system is no longer used and Wales is once
again 100% diesel
Slide 22
Golden Valley BESS Largest battery in the world Nickel-Cadmium
chemistry 27 MW 6.25 MWh capacity Electrical Energy equivalent to
~400 gallons of fuel It works
Slide 23
Questions?
Slide 24
For more information on the Alaska Center for Energy and Power,
please visit http://www.uaf.edu/acep/ Or call (907) 474-1145 Alaska
Center for Energy and Power http://www.uaf.edu/acep/ (907)
474-1145
