Fostering the development of cost

effective and innovative energy solutions for Alaska and beyond

Energy Storage Overview

Gwen Holdmann

Alaska Center for Energy and Power

ACEP (907) 474 1143 www.uaf.edu/acep

Alaska  Center  for  Energy  and  Power      h5p://www.uaf.edu/acep/        (907)  474  1145  

Overview  

•  Why?  •  Types  of  storage  •  ACEP  ba5ery  tesHng  experiences  •  Energy  storage  in  Alaska    

Why  Storage  and  Why  Now?  

•  Balance  supply  and  demand  •  Load  leveling  •  Load  shiOing  •  UPS  –  UninterrupHble  Power  Supply  •  PotenHal  to  save  fuel  and  $$$    

Types  of  Storage  

•  PotenHal  – ElevaHon  difference  – Electrochemical  – Super  capacitors  – Chemical  – MagneHc  – Mechanical  

•  KineHc  •  Thermal  

Overview  

Source:  U.S.  Energy  InformaHon  AdministraHon,  based  on  Energy  Storage  AssociaHon  

Compressed  Gas  

Hydroelectric  

•  Reservoir  storage  •  Energy  =  mgh  •  Pumped  hydroelectric  

~70%  efficient  Needs  the  right  circumstances  ElevaHon  change  

         

Super  Capacitors  

•  “Ba5ery”-­‐like  characterisHcs  •  Extremely  rapid  charge  and  discharge  •  Virtually  no  degradaHon  •  High  self-­‐discharge  rate  •  Not  suitable  for  long  term  storage  

Flywheels  

•  KineHc  energy  storage  •  Energy=1/2  mv2  

•  Changed  from  heavy  rotors  to  fast  rotors  •  Turn  around  efficiency  up  to  85%  •  Short-­‐term  storage  •  Containment?    

BaAeries  

•  Electrochemical  storage  •  Can  be  efficient  •  The  technology  is  rapidly  improving  •  Most  types  degrade  

Other  examples  •  Liquid  metal  ba5ery  •  MagneHc  storage  •  Thermal  storage  •  Hydrogen  •  Biomass  •  And…  

Resident  installs  thermal  electric  storage  system    (from  Intelligent  Energy  Systems  website)  

Power  System  IntegraEon  Lab  

Power  System  IntegraEon  Lab  

Flow  BaAery  TesEng  at  ACEP  

Flow  BaAery  TesEng  at  ACEP  

•  Vanadium  redox  ba5eries  •  VRB  and  Prudent  Energy  •  Turn  around  efficiency  65%-­‐75%  •  Very  low  degradaHon  •  High  self-­‐discharge  rate  •  The  “stack”  was  reliable  •  The  VRB  balance  of  plant  was  not  

 

Pumps  

Leaks  

Existing Alaska Battery & Flywheel Projects

Wales

Metlakatla

Kokanok

GVEA (Fairbanks)

Lime Village Kwigillingok

Kodiak

Kotzebue

St Paul

Usibelli  Coal  Mine  

•  Electrically-­‐operated  dragline  •  6  MW  draw,  2  MW  regeneraHon,  60  second  cycle  Hme  

•  Caused  grid  stability  problems  •  40  ton,  1000  rpm  Flywheel  was  installed  and  reduced  the  fluctuaHons  from  8MW  to  .5  MW  

•  Installed  in  1982  and  sHll  in  use  

Premium  Power  Ba5ery  

•  500  kW,  3.4  MWhr  •  Delivered  to  Kotzebue  in  October  2011  •  Zinc-­‐Bromide  chemistry  •  Intended  to  provide  storage  during  Hmes  of  excess  wind.  

•  Never  commissioned  •  Being  returned  to  the  manufacturer…  

Wales  

•  Wind-­‐diesel  hybrid  system  •  Ba5ery  and  thermal  storage  enabled  diesel-­‐off  operaHon  

•  System  proved  it  could  work  •  For  a  variety  of  reasons,  the  system  is  no  longer  used  and  Wales  is  once  again  100%  diesel  

Golden  Valley  BESS  

•  Largest  ba5ery  in  the  world  •  Nickel-­‐Cadmium  chemistry  •  25  MW  •  6.25  MWh  capacity  •  Electrical  Energy  equivalent  to  ~400  gallons  of  fuel    

•  It  works  

Conclusions  

•  Doable  •  Expensive  

•  No  magic  bullet  

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      

h5p://www.uaf.edu/acep/        (907)  474-­‐1145