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HomeMy WebLinkAbout8-12-2012 Deering CommentsMayor  Stephanie  Scott   Haines  Borough,  Alaska      12  August  2012         Dear  Mayor  Scott,     Following  our  discussions  regarding  my  (and  others)  concerns  about  the  Alaska   Energy  Engineering  (AEE)  report  studying  the  feasibility  of  wood  pellet  boilers  for   several  Borough  buildings,  Mr.  Darsie  Culbeck  asked  if  I  could  briefly  evaluate  the   potential  of  converting  the  Chilkat  Center  to  pellet  heat.    I  spent  a  few  hours  this   weekend  on  that  effort.     Pease  note  that  the  following  document  does  not  reflect  a  position  of  the  United   States  Coast  Guard.    I  am  providing  this  analysis  as  a  private  citizen  with  a  strong   interest  in  our  regional  energy  strategy.    On  1  October  I  will  be  moving  from  the   Coast  Guard  to  the  Forest  Service  on  a  one-­‐year  special  assignment  to  lead  the   development  of  a  regional  biomass  energy  strategy.    This  effort  is  a  ‘warm-­‐up’  for   that  larger  assignment.    I  have  no  financial  stake  in  the  biomass  industry,  and  no   financial  stake  in  the  outcome  of  the  Haines  decision.    I  am  not  being  financially   compensated  for  this  analysis.     I  must  preface  this  exercise  with  several  significant  caveats:     1. I  have  never  been  the  Chilkat  Center.    I  have  limited  knowledge  about  its   heating  systems  or  energy  performance.    All  of  my  analysis  is  based  on  a  few   pieces  of  known  data  and  some  (hopefully)  reasonable  assumptions.    For  that   reason  I  have  attempted  to  lean  toward  the  conservative  side  with  my   estimates.           2. The  AEE  report  states  that  the  replacement  of  the  heating  system  would   likely  cost  about  $400,000,  and  the  lifecycle  cost  would  be  about  $600,000,   but  it  provides  little  analysis  and  no  calculations  to  support  those  statements.     Note  that  the  AEE  report  also  finds  that  pellet  heat  would  be  cost  effective   based  on  current  energy  usage.     3. Based  on  online  drawings,  it  appears  that  the  Chilkat  Center  is  roughly   20,000  gross  square  feet  in  size.    That  is  what  I  based  equipment  sizing  on.    A   25%  deviation  in  either  direction  won’t  significantly  change  the  results.   4. I  assumed  that  adequate  3-­‐phase  electrical  service  was  available  at,  or  could   be  brought  into  the  building  at  a  reasonable  expense.   5. I  also  assumed  that  the  electric  utility  could  provide  short-­‐term  backup   heating  energy  as  necessary  year-­‐around  (though  perhaps  not  economically).     I  also  assumed  that  it  could  easily  provide  for  all  of  the  building’s  heating   load  during  the  summer,  when  the  hydro  system  was  likely  to  have  excess   capacity  going  to  waste.     6. The  AEE  report  refers  to  recent  energy  assessments  of  the  building  that   indicate  that  the  building  is  not  operating  in  an  efficient  mode.    I  have  not   seen  those  reports  but  I  made  allowances  for  increased  building  efficiency  in   my  analysis,  and  generally  assumed  a  20%  heating  energy  reduction,  which   can  be  modified  to  suit  reality  in  the  spreadsheet  included.    In  general,   efficiency  improvements  yield  the  largest  payback  on  an  investment,  so   should  be  pursued  first  if  possible.     7. I  used  a  delivered  pellet  price  of  $338  per  ton.    This  is  the  price  that  was   awarded  last  week  in  the  Defense  Logistics  Agency’s  Coast  Guard  pellet   contract  for  AIRSTA  Sitka.    The  contract  was  competitively  advertised,  with   multiple  bidders.    Sealaska  was  not  the  winning  supplier.    Even  if  the  original   study  price  of  $360/ton  is  used,  the  results  do  not  significantly  change.     8. I  have  accepted  the  AEE  inflation  rate  assumptions  for  oil  and  pellets,  though   there  has  been  considerable  debate  as  to  whether  they’re  suitable.    For  the   purposes  of  my  rough  analysis  they’re  ‘close  enough’.     9. And  finally,  this  analysis  was  conducted  over  a  few  brief  hours  during  the   weekend.    It  almost  certainly  contains  errors  and  oversights,  despite  my  best   efforts.    It  has  been  briefly  peer  reviewed  by  an  engineer  colleague.    Caveat   emptor.     The  two  boilers  at  the  Chilkat  Center  have  reached  the  end  of  their  operational  lives.     The  approach  proposed  by  AEE  is  to  replace  the  two  existing  oil  boilers  inside  the   building  with  new  oil  boilers,  and  then  add  another  pellet  boiler  in  a  container   exterior  to  the  building.    The  AEE  report  largely  used  the  same  approach  for  the   other  Haines  Borough  buildings.    As  has  been  pointed  out  in  my  comments  on  the   AEE  report,  along  with  comments  by  the  Forest  Service  and  Alaska  Energy   Authority,  the  AEE  approach  does  not  yield  an  optimal  solution  for  Haines,  for   numerous  reasons.     I  recommend  consideration  of  a  different  approach:  Remove  both  oil  boilers  and   replace  them  with  a  single  wood  pellet  boiler  and  a  single  electric  boiler,  both   contained  inside  the  Chilkat  Center  mechanical  room  (assuming  space  permits).     While  a  pellet  boiler  may  be  somewhat  larger  than  a  comparable  oil  boiler,  an   electric  boiler  is  much  smaller,  so  space  should  not  be  an  issue.     A  pellet/electric  hybrid  offers  several  advantages.    Pellet  fuel  is  by  far  the  lowest   cost  energy  of  the  three  sources  evaluated  here,  and  should  be  the  preferred  fuel   source  for  most  of  the  heating  demand.    However,  during  periods  of  low  heating   demand,  such  as  late  spring,  summer,  and  early  fall,  a  combustion  boiler  (pellet  or   oil)  is  not  operating  in  its  most  efficient  mode,  with  short  cycling  and  a  significant   proportion  of  jacket  heat  losses.    At  those  times  an  electric  boiler  shines,  as  it   operates  at  near  100%  efficiency  regardless  of  load.    The  Coast  Guard  has  taken  this   approach  with  its  conversion  to  pellet  heating  in  Sitka  –  it  has  added  an  electric   boiler  for  summer  heating  demand,  when  the  electric  utility  has  spare  capacity   going  to  waste  over  the  dam  spillway.           During  the  warmer  months,  the  electric  boiler  could  be  used  exclusively  to  meet  the   buildings  heating  demand.    While  electric  rates,  at  $0.25/kWh,  are  fairly  high,  the   actual  heating  demand  during  the  5  warmest  months  only  represents  19%  of  the   total  annual  heating  load,  based  on  Haines  climate  data.    The  period  of  transition  to   electric  heat  is  entirely  under  the  control  of  the  facility  manager,  and  can  be   adjusted  based  on  a  number  of  factors  such  as  available  excess  hydropower  (in   coordination  the  Haines  electric  utility),  the  current  weather,  the  current  cost  of   pellets  and  electricity,  planned  maintenance  on  one  of  the  boilers,  etc.    As  the   building  staff  learns  the  new  configuration,  they  will  be  able  to  optimize  its   operations  for  best  economics.    I  assumed  that  a  simple,  inexpensive  control  system   would  be  adequate  to  shift  duties  between  the  two  boilers,  and  a  trained  facility   operator  could  make  intelligent  decisions.         In  the  winter,  the  electric  boiler  could  provide  peaking  supply  during  the  few   instances  where  the  pellet  boiler  could  not  meet  the  heating  demand  during   extreme  cold  spells.    This  would  allow  the  pellet  boiler  to  be  sized  to  a  smaller   capacity,  thus  reducing  capital  costs  and  increasing  boiler  efficiency.         Note  that  shifting  to  electric  heat  for  several  months  out  of  the  year  provides  an   additional  benefit.    Electric  boilers  are  nearly  maintenance-­‐free.    Besides  daily   checks  of  the  system  as  part  of  normal  facility  rounds,  electric  boilers  require  little   ‘care  and  feeding’.    By  idling  the  pellet  boiler  for  possibly  5  months  per  year,  that   significantly  reduces  overall  annual  maintenance  expenses,  to  below  that  of  the   status  quo  oil  boilers.       Note  that  the  AEE  report  indicates  (Fig.  1:    Cost  of  Heat  Comparison)  that  electric   heating  in  Haines  is  projected  to  become  less  expensive  than  the  cost  of  oil  heating   in  around  13  years,  so  installing  an  electric  boiler  is  consistent  with  longterm   trends.    If  additional  hydro  capacity  comes  online  in  Haines  in  the  future,  resulting   in  decreased  electrical  rates  and  increased  capacity,  the  electric  boiler  is  in  position   to  take  advantage  of  it.    Likewise  if  other,  currently  unforeseen,  electrical  power   generation  sources  develop.    Investing  in  new  oil  boilers,  which  will  remain  in  place   for  the  next  30  years,  is  an  investment  in  a  future  almost  guaranteed  to  yield  much   higher  heating  expenditures.      The  subject  of  redundancy  was  a  key  discussion  of  the  AEE  report.    The  report   provided  fully  redundant  solutions  for  each  building  when  looking  at  pellet  heating,   as  required  in  the  contract  RFP.    The  AEE  approach  for  each  Haines  Borough   building  was  to  include  or  replace  the  existing  oil  boilers,  and  then  add  pellet  boilers   in  an  exterior  container  or  building,  and  as  noted  above,  that  was  the  approach   recommended  by  AEE  for  the  Chilkat  Center.    Unfortunately,  the  AEE  report  failed  to   provide  a  redundant  solution  when  the  report  evaluated  the  status  quo  situation,   meaning  most  buildings  only  ended  up  with  one  boiler,  as  they  previously  had.    This   led  to  a  highly  skewed  lifecycle  cost  comparison  between  a  one-­‐boiler  and  a  two-­‐ boiler  system.    Not  surprisingly,  a  single  boiler  costs  less  than  two  boilers  when  it   comes  to  capital  costs  and  maintenance  expenses.    An  ‘apples-­‐to-­‐apples’  comparison   would  have  added  a  second  oil  boiler  in  an  exterior  container  for  the  status  quo   option  –  the  lifecycle  costs  would  likely  have  been  significantly  different  then.     In  my  approach  to  the  Chilkat  Center,  the  electric  boiler  would  be  capable  of   providing  100%  backup  heat.    Obviously,  at  $0.25/kWh,  it  would  not  be  desirable  to   run  the  electric  boiler  for  long  periods  during  the  winter.    That  might  also  add   undesirable  load  on  the  electric  utility.    But  a  backup  system  is  not  intended  for   longterm  usage,  with  the  concept  being  that  the  primary  boiler  would  be  brought   back  online  promptly.     Another  backup  option  that  the  Coast  Guard  has  adopted  at  AIRSTA  Sitka  appears  to   have  promise  for  Haines.    We  have  purchased  a  portable,  trailer-­‐mounted  oil  boiler,   complete  with  an  onboard  oil  tank.    This  boiler  is  sized  to  meet  the  largest  building’s   heating  demand.    We  have  plumbed  quick  disconnects  into  each  building’s  heat   distribution  system  (a  simple  &  inexpensive  modification)  which  allows  us  to   quickly  plug  in  the  portable  boiler  in  the  event  of  a  primary  boiler  failure.    We  are   even  considering  modifying  other  Coast  Guard  buildings  outside  of  Sitka  with  this   feature  so  if  we  experience  a  boiler  failure  we  can  quickly  transport  the  portable   boiler  to  the  location  via  ferry  or  C130  airplane.     Haines  could  use  this  same  approach.    Purchase  a  single  portable  boiler  (oil  or   pellet)  large  enough  to  meet  the  load  of  the  Chilkat  Center  (or  other  large  building),   and  then  equip  all  of  the  Borough  buildings  (Administration,  Library,  Vocational  Ed,   High  School,  Chilkat  Center…)  with  connection  fittings  to  accommodate  it.    The   boiler  could  be  drained  of  water  when  not  in  use,  or  stored  in  a  heated  structure,  so   the  use  of  glycol,  and  the  associated  complexities  of  heat  exchangers  and  pump   systems  could  be  avoided.  By  meeting  this  critical  backup  function  with  the  portable   boiler,  it  would  decouple  that  role  from  the  pellet  boilers,  allowing  them  to  replace   the  existing  oil  boilers  inside  the  buildings,  thus  greatly  reducing  the  capital  and   lifecycle  costs  of  the  pellet  boiler  solution.    My  expectation  is  that  the  pellet  boiler   solution  would  then  have  the  lowest  lifecycle  cost  for  every  building,  even  including   the  purchase  of  the  portable  boiler.    Haines  would  also  benefit  by  owning  a  highly   flexible  backup  heating  solution,  which  might  be  applicable  to  several  other  facilities   in  Haines.    Installing  electric  boilers  in  each  building  could  also  satisfy  the  backup   requirement,  while  providing  off-­‐season  heating  efficiency  opportunity.                Following  are  my  findings.    Pease  note  that  I  didn’t  run  them  at  various  inflation   scenarios,  simply  using  the  ‘base  case’  numbers  except  as  noted.                   Life  Cycle  Cost  Comparison  –  Chilkat  Center             Heating  System  Construction  Operating  Energy  Total  LCC   Status  Quo:  Renew  Two  Oil  Boilers  $250,000  $111,825  $1,161,027  $1,522,852   Pellet  &  Electric  boiler  $345,153  $53,458  $740,139  $1,129,023       I  hope  you  will  find  this  analysis  helpful.    Please  note,  again,  that  it’s  based  on   numerous  assumptions  that  could  not  be  validated  over  a  short  weekend.    If  you   provide  me  additional  information  regarding  the  Chilkat  Center,  I  can  endeavor  to   update  it  more  fully.    I  am  providing  my  spreadsheet,  which  you  are  free  to  modify   in  an  attempt  to  find  your  optimal  solution.    Regardless,  before  making  any  final   decisions  on  your  path  forward,  I  recommend  bringing  in  an  independent  third   party  to  help  evaluate  your  options,  perhaps  as  part  of  the  design  process.     I  would  also  recommend  reevaluating  the  other  AEE  recommendations  from  the   perspective  of  adding  electric  boilers  and/or  a  portable  backup  boiler.    My  belief  is   that  the  lifecycle  costs  will  prove  considerably  more  favorable  for  a  pellet  boiler   solution,  though  I  have  not  performed  a  detailed  lifecycle  cost  analysis  to  confirm  it.     Again,  it  may  be  appropriate  to  have  an  independent  third  party  make  this   evaluation.     Making  longterm  investments  in  oil  heating  is  not  a  prudent  strategy  for  Southeast   communities.    There  is  little  doubt  that  oil  prices  will  continue  to  increase  faster   than  the  rate  of  inflation,  and  will  be  accompanied  by  future  price  shocks  due  to   global  market  and  geopolitical  factors  beyond  Alaskans’  ability  to  predict  or  control.     Investing  in  developing  our  local  energy  resources  is  our  best  hedge  for  the  future.     Biomass  is  an  abundant  and  available  resource  that  has  barely  been  tapped  in   Southeast.    Meeting  a  substantial  portion  of  the  heating  (and  possibly  some   electrical  power)  needs  of  Southeast  Alaska  by  the  responsible  and  sustainable  use   of  biomass  is  entirely  possible.    Failure  to  do  so  will  lead  to  unaffordable  heating   costs  and  unsustainable  loads  on  our  regional  hydropower  resources.     The  development  of  a  regional  or  local  biomass  industry  could  also  lead  to  a   significant  price  reduction  for  biomass  fuel.    As  the  AEE  report  notes,  transportation   accounts  for  56%  of  the  cost  of  wood  pellets,  imported  from  the  Lower  48  and   Canada.    Regionally  produced  pellets  could  greatly  reduce  that  transportation  cost.     As  provided  to  you  previously  by  Dan  Parrent  of  the  Forest  Service,  Tongass  Forest   Enterprises  of  Ketchikan  has  published  a  rate  sheet  quoting  local  Ketchikan   customers  a  fixed,  five-­‐year  contract  to  supply  locally  produced  pellets  at  $275/ton,   24%  less  than  the  quoted  price  used  in  AEE’s  report,  and  35%  less  than  the  Chikoot   Indian  Association’s  cost.    Is  it  possible  that  a  similar  ‘home-­‐grown’  fuel  supply   could  be  developed  for  Haines,  providing  low-­‐cost  biomass  fuel  while  creating  local   jobs  and  economic  activity?           The  study  performed  by  AEE  has  yielded  a  significant  side  benefit.    It  has  generated   discussion  within  the  community  about  its  energy  economy.    This  is  a  discussion   that  will  need  to  take  place  in  communities  throughout  Alaska.    No  energy  solution   exists  in  a  vacuum.    Decisions  we  make  about  oil,  hydropower,  biomass,  and  other   potential  energy  supplies  and  utilization  need  to  be  coordinated  throughout  the   community  to  achieve  the  best  outcomes.    The  decisions  made  by  the  Haines   Borough  are  highly  relevant  to  that  discussion.     If  you  have  any  questions  regarding  this  document,  or  if  I  can  be  of  any  further   assistance,  please  don’t  hesitate  to  ask.    Feel  free  to  share  this  as  you  see  fit.         Bob  Deering   Juneau,  AK