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ChargeFlex – Increased  grid  capacity  for  EV  chargingthrough  smart  management  of  available  flexibility

nordic SMART  electric transport  conference,  Oslo  November  20th 2015

Stig  Ødegaard  Ottesen,  Head  of R&D  eSmart  Systems/PhD Candidate NTNU

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Presentation  outline§ Problem  description§ The  ChargeFlex project§ Smart  Charging strategies§ eSmart  Systems

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Problem  description§ Simultaneous  charging  of  EVs  may  lead  to  problems  in  

the  power  system:  Violation  of  capacity  limits

§ Most  probable  in  the  local  distribution  grid  and  at  the  end-­‐users’  premises• Overload  of  transformers,  lines/cables  or  fuses• Economic  problem:  Power/capacity  based  tariffs

§ Possible  solutions• Reinforce  the  grid  • Introduce  battery  banks/local  generation• Control  the  charging  process  -­‐ “Smart  Charging”• Or  a  combination

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The  ChargeFlex project

§ 3  years,  started 2015,  app.  12  MNOK§ Funded by  RCN  Pioneering research and  innovation§ «Increased grid  capacity for  EV  charging through smart  management  of available flexibility»

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Process and  research need

§ Big  data§ Uncertainty§ Dynamics

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Pilots

Ladetorget,  Moss Remmen  kunnskapspark,  Halden

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Charging  site  model

§ Our  problem:  How  to  schedule• Power  to  each  charging  point• Charging/discharging  each  storage  unit• So  that  

• The  capacity  limit  is  not  violated• The  charging  demand  is  met

§ eSmart  Systems  has  developed  two  methods1. A  rule-­‐based  algorithm  2. An  optimization-­‐based  method

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Common  for  both  methods§ We  split  planning  horizon  into  periods  (time  slots)§ Each  EV  

1:  arrives  to  the  charging  site  and  connects  to  a  charging  point,  starts  charging,  2:  gets  fully  charged,  3:  disconnects  and  departs.

§ Each  time  we  enter  a  new  period,  we  receive  new  information  and  we  decide  new  schedules  (iterative  planning)

§ We  base  our  decision  only  on  available  information

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Rule-­‐based  method

§ Simple  rules,  easy  to  implement§ Myopic,  only  see  “here-­‐and-­‐now”,  does  not  

require  additional  information

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Optimization-­‐based  method

§ EV  drivers  enter  information  about  charging  demand  and  preferred/expected  time  for  departure

§ We  have  information  to  postpone   some  charging  and  still  deliver  the  demand  § We  have  flexibility  and  formulate  the  problem  as  a  MIQP§ Objective:  To  deliver  as  much  of  the  charging  demand  as  possible  – if  not  possible:  

to  distribute  the  not  delivered  demand

§ Subject  to  not  violating  the  charging  site  capacity  limit

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Case  study

§ We  have  implemented  the  two  scheduling  methods§ They  are  tested/verified  in  a  case  study

• A  projected  charging  site  outside  office  building• Charging  data  from  a  similar  type  of  building• We  have  sampled  datasets

§ We  analyze  several  combinations  of  technology  and  control  method§ Research  questions:1. If  we  are  going  to  deliver  all  EV  charging  demand,  what  is  the  least  maximum  imported  power  needed?2. If  the  maximum  imported  power  is  given,  how  will  the  different  methods  deliver  the  EV  charging  

demand?

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Summary  of  findings

§ We  perform  a  case  study  to  evaluate  the  methods:• Largest  reduction  in  maximum  power  by  introducing  

either  Smart  charging  or  storage• Combination  of  Smart  charging  and  storage  further  

decreases  max  power,  but  only  slightly• Optimization-­‐based  method  outperforms  Rule-­‐based   in  

all  situations  except  when  situation  is  very  limited  or  only  slightly  limited

• Difference  between  the  two  methods  decrease  when  introducing  storage  and  generation

§ Methods  will  be  tested  in  pilot  site  in  the  ChargeFlexproject

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eSmart  Systems

§ Startup-­‐company,  established 2013§ «Child»  of NCE  Smart  Energy  Markets§ Located in  Halden§ Funded partly through Innovation Norway,  utilities and  employees§ App.  30  employees,  3  full-­‐time  researchers§ Business  idea based on 2  mega  trends

The Nexus of ForcesSource: Gartner 2013

Disruptive Innovation the Way ForwardFor High Value Adding Economy

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Thank you for  your attention!stig.ottesen@esmartsystems.com  +47  90973124