=
vs.
Pesky
Data
BelieveThisandYouCanUse
ThermalStorageto
SolveEverything
*
…un:ltheRealWorldGetsintheWay
HenrySpindler,Ph.D.DCMLogic
NEBHX2017
*NBAMemphisGrizzliescoachDavidFizdale
The“Conven:onal”WaytoDo
ThermalStorage
En#ty
ThermalStorageVolume
Natureof
Volume
Guidance
NYSERDA
2gal/kbtuh
Minimum
requirement
Required
USFS/WES
1gal/kbtuh(chips)
0.75gal/kbtuh(pellets)*
Ruleofthumb
Advantageous
Viessmann
1galper1.3kbtuh,or
0.77gal/kbtuh
Recommended
-
Belief
=Basedonatheoryor
datasupportunknown
*Technicalinforma:onprovidedbyWES
Tank
Stra#fica#on
=Supportedbydatafrom
realworldopera:on
Whatarewealltryingtoaccomplish?
OverallGoal
HighEfficiency
LowEmissions
Responsiveness
Whatcharacteris:csarenecessary?
(maybe…)
OverallGoal
HighEfficiency
LowEmissions
Responsiveness
ProposedPlantCharacteris:cs
toAchieveOverallGoal
ExtendedCycleLengths
BoilerRun:meat100%Maximized
HighResponsivenesstoImposedLoads
Whatprovidesthosecharacteris:cs?
(maybe…)
OverallGoal
HighEfficiency
LowEmissions
Responsiveness
ProposedPlantCharacteris:cs
toAchieveOverallGoal
ExtendedCycleLengths
BoilerRun:meat100%Maximized
HighResponsivenesstoImposedLoads
ProposedMethodtoAchievePlantCharacteris:cs
InstallaPar:cularVolumeBufferTank
CoreBeliefsaboutThermalStorage
•  ThermalStorageVolumeAffectsCycleLength
•  ThermalStorageEnsuresHighFiringRate
Opera:on
•  ThermalStorageVolumeAffects
ResponsivenesstoChangingLoads
•  ADoseofReality—notBufferin
Take2gal/kbtuhand
callmeinthesummer
Belief
BoilerCyclingisaProblemAND
“ProperlySized,ProperlyDeployed”
ThermalStorageMinimizesCycling
(“PrimerintheUseofThermalStorage,”USFS/WES)
(“GuideforM&VforWood-Hea:ngSystems,”NYSERDA)
Belief
Belief
Real
World
ButCycleLengthIsUncorrelated
withThermalStorageSizing!
3.5
60%
%ofmaxcyclelength
Cyclelength
0.5 1 1.5 2 2.5 3
StorageVolume(gal/kbtuh)
ShoulderSeasonAnalysis
RequiredTS
volume/output
3.5
80%
CycleLengthIncreasesDrama:callywith
MoreStorage,thenDiminishingReturns
Storagevolume/output
3.0
Hea:ngSeasonAnalysis
100%
40%
20%
0%
0.0
0.5
1.0
1.5
2.0
2.5
120%
100%
80%
60%
40%
20%
0%
0
No“SweetSpot”forSizingRuleofThumb
CoreBeliefsaboutThermalStorage
•  ThermalStorageVolumeAffectsCycleLength
•  ThermalStorageEnsuresHighFiringRate
Opera:on
•  ThermalStorageVolumeAffects
ResponsivenesstoChangingLoads
•  ADoseofReality—notBufferin
Take2gal/kbtuhand
callmeinthesummer
Belief
IfonlytherewereThermalStorage,there
wouldbeless:meatLowFiringRate…
%ofHea#ngTime
50%
Belief
40%
30%
20%
FrequencyofFiringRates,2-boilerplant,
2016-2017hea:ngseason
10%
0%
FiringRate
…ExceptthereISthermalstorageinthisinstalla:on!
ThermalStorageprovidessignificant
run:meatHighFiringRate...
Belief
%ofHea#ngTime
50%
40%
30%
FrequencyofFiringRates,1-boilerplant,
11-12/2016
20%
10%
0%
10-20% 20-30% 30-40% 40-50% 50-60% 60-70% 70-80% 80-90% 90-100%
FiringRate
…ExceptthereISNOthermalstorageinthisinstalla:on!
Whydowecare?
BecauseallboilerEfficiency&Emissions
sufferatLowFiringRates,right?
Belief
Labtestdatashowsliqleefficiencyoremissions
degrada:onbetweennominalloadand30%ofnominal
100%
30%
Real
World
Source:Viessmann
Efficiency&EmissionsDONOTsufferatLowFiringRatesinallcases.
(¡¿Islabdatarelevantintherealworld?!)
CoreBeliefsaboutThermalStorage
•  ThermalStorageVolumeAffectsCycleLength
•  ThermalStorageEnsuresHighFiringRate
Opera:on
•  ThermalStorageVolumeAffects
ResponsivenesstoChangingLoads
•  ADoseofReality—notBufferin
Take2gal/kbtuhand
callmeinthesummer
Belief
“ProperlySized”ThermalStorage
EnsuresResponsiveness...
Belief
...butstoragevolumeandresponsivenessareuncorrelated!
BPE,ameasureof
“Responsiveness”
100%
80%
60%
Nocorrela:on
40%
20%
n=47
0%
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
Storagetanksize/capacityofindividualboilerinplant(gal/kBTUh)
CoreBeliefsaboutThermalStorage
•  ThermalStorageVolumeAffectsCycleLength
•  ThermalStorageEnsuresHighFiringRate
Opera:on
•  ThermalStorageVolumeAffects
ResponsivenesstoChangingLoads
•  ADoseofReality—notBufferin
Take2gal/kbtuhand
callmeinthesummer
Belief
Promiseof“ProperlySized”Thermal
StorageFailstoDeliveronAllCounts
OverallGoal
?{
✖
HighEfficiency
LowEmissions
Responsiveness
ProposedPlantCharacteris:cs
toAchieveOverallGoal
✖
✖
✖
✖
ExtendedCycleLengths
BoilerRun:meat100%Maximized
HighResponsivenesstoImposedLoads
ProposedMethodtoAchievePlantCharacteris:cs
InstallaPar:cularVolumeBufferTank
Evendesirability
oftheseis
ques:onable!
8
QualityofControlsDoesAffect
CycleLengthANDResponsiveness
100%
Controls1
90%
Controls2
6
BPE,ameasureof
“Responsiveness”
Hea:nghoursperstart
7
5
4
3
2
Controls1
Controls2
80%
88%
70%
60%
50%
55%
40%
30%
20%
1
10%
0
0%
>60kW
boilers
N=10,35
≤60kW Single-boiler Before/Awer
boilers
plants
aControls
Retrofit
N=31,13 N=13
N=1
ControlType
“Controls”here=
•  stagingcontrol
•  modula:oncontrol
Source:Aselec:onofboilersmonitoredbyDCMLogic2013-2016.
Conclusions
Xgal/
kbtuh
Goal
Plant
Characteris:cs
Method
•  Sugges:ngacertainamountofthermalstorage
forallbiomassboilersisclearlyindefensible
•  AllthistalkaboutTSiscompletelymissingthe
point!
–  #1TASK:UseDATAtodetermineexactlywhatwe
wanttheboilers/boilerplanttodoinordertomeet
ouroverallgoals
–  #2TASK:UseDATAtodeterminehowtodo#1.
•  Belief-basedasser:onsarenothelpfulin
improvingemissions,efficiencyand
responsiveness
•  Beware“Conven:onal”Wisdom!
*
*NBAMemphisGrizzliescoachDavidFizdale
=
vs.
Pesky
Data
BelieveThisandYouCanUse
ThermalStorageto
SolveEverything
*
…un:ltheRealWorldGetsintheWay
HenrySpindler,Ph.D.DCMLogic
NEBHX2017
*NBAMemphisGrizzliescoachDavidFizdale