CLEANROOM ENERGY REDUCTION - ISPE Boston€¦ · CLEANROOM ENERGY REDUCTION: POSSIBILITIES FOR NOW & IN THE ... The standard industry model for cleanroom design & operation has not

CLEANROOM ENERGY REDUCTION: POSSIBILITIES FOR NOW & IN THE

NEAR FUTURE

Keith Beattie of EECO2

ISPE Boston Area Chapter Product Show

18th September 2019

Connecting Pharmaceutical Knowledge ispe.org

1. Introduction

2. Cleanroom development history vs What we know

today

3. 3 great energy reduction strategies – guaranteed to

work in cleanrooms

4. Future opportunities

5. Summary

AGENDA


The standard industry model for cleanroom design & operation has not changed for around 50 years.

3

A BRIEF HISTORY

1867 Joseph

Lister uses

Carbolic acid

as antiseptic

1940’s good

ventilation

hinders

infections

1961 Laminar

airflow used in

surgery (Charnley

& Howorth)

WW2 Cleanrooms developed

to aid production of precision

mechanical parts

1985 FFU

developed

1999 ISO

standards

published

1962 Whitfield

creates ultra-

clean room

2000 ULPA

filters

introduced

1978

Multi-zone

cleanroom

concept

First commercial

application of adaptive

cleanroom control in

pharma manufacturing?

2000 1980 1960 1940 2019


• Critical for product protection

• Performance (cleanliness) is dependent on many factors influencing:

• Contamination infiltration – from less clean areas

• Contamination generation – people, process & equipment

• Contamination removal effectiveness – design, filtration

• Air Change Rates are not a reliable indicator of cleanroom performance.

• HVAC systems are designed, constructed, commissioned & validated for “worst case” scenarios.

• Very energy intensive spaces (up to 80% of energy consumption is HVAC) – no correlation to production output/volume

4

WHAT WE KNOW ABOUT CLEANROOMS TODAY


0

500

1,000

1,500

2,000

2,500

3,000

Semicoductorfacility

Non-sterileOintments

Asepticproduction

OfficeBuilding(Typical)

Energy Intensity by Class, W/m2

NC ISO 8 ISO 7 ISO 6 ISO 5

5

ENERGY INTENSITY VS AREA

Typical % Area

NC ISO 8 ISO 7 ISO 6

Data Source: Cleanroom Technology article “Saving energy in cleanrooms” by

Alexander Fedotov (Invar-project), published 04 Aug 2014.

Data Source: eeco2 approximation

Connecting Pharmaceutical Knowledge ispe.org 6

PHARMACEUTICAL HVAC ENERGY REDUCTION STRATEGIES:

Reduce quantity of air

Reduce amount of conditioning

Condition efficiently

Maintain efficiency

Improve

robustness &

compliance

ENERGY REDUCTION:

TODAY WHAT YOU CAN DO TODAY IN YOUR FACILITIES:

• AIR CHANGE RATE REDUCTION

• SETBACK

• CONTROLS OPTIMISATION


• From the fan affinity laws, fan power is related to airflow by a “cube” law.

• A small reduction of airflow (10% in this case), gives a 28% reduction in the fan power consumed.

• That’s why air change rate reduction is such an effective energy reduction strategy.

8

FAN AFFINITY LAWS: WHY AIRFLOW IS SIGNIFICANT FOR ENERGY REDUCTION

10%

28%


1. HOW MUCH AIR DO WE NEED?

24

18

22

2

5

7 6

0

5

10

15

20

25

30

Original Design Site Data BaselineMeasured

New Design(Particle

ConcentrationControl)

New Design (HeatGain Removal)

New Design(Pressurisation)

New FinalBalancing

Site Standard

(Min ACPH)



24

18

22

2

5

7 6

0

5

10

15

20

25

30

Original Design Site Data BaselineMeasured

New Design(Particle

ConcentrationControl)

New Design (HeatGain Removal)

New Design(Pressurisation)

New FinalBalancing

New Site

Standard (Min

ACPH)

Site Standard

(Min ACPH)

Supply Air -72%

Fan Energy -81%


≥0.5 micron shows very small increase

≥5.0 micron shows larger increase but greatly under compliance limits

Improved diffusers selected for revised airflow and improved mixing will mitigate the 5.0 micron increases

Trial demonstrates ACPH’s can be reduced… …without impact on quality compliance

11


0.5μm 5.0μm

5% 9%

2% 4% 4% <1%

1% 7%

6% 19% 1% 5%

1% 4%

% of class limit


• No people = no contamination source

• No production = no risk to product

• When no production turn down air supply rate (+ relax temp/humidity setpoints)

It’s a good idea to:

• Keep people out of area whilst in setback mode

• Provide visual indication for setback mode – to alert operators

• Qualify return to normal operation (particles + micro)

• Might require CV boxes on fresh air to maintain pressure

12

2. SET BACK (TURN-DOWN) – NON PRODUCTION TIME


19°C

23°C

21°C

27°C

3. BAS CONTROLS – FOR EFFICIENCY


19°C

23°C

21°C

27°C

3. BAS CONTROLS – FOR EFFICIENCY

Cooling valve is shown closed,

and heating valve is 100% open,

yet temperature decrease

observed from 23°C to 19 °C OA damper

shown as closed.

Is it really?

Whenever we see valve positions at

100%, then this is often an indication

something is not right. Most likely is

cooling valve has failed or is in manual

bypass.


Part 16 – currently at final review stage (FDIS)

• Expected publication around Q4 2019

• What’s in it?

• Process to follow

• Debunks air change rate myth

• Lots of examples of what to do

• Helpful calculations

• Benchmarking techniques

15

……AND FINALLY: ISO 14644-16

Design cleanroom with efficiency in mind & use performance data in

use to ‘tune’ cleanroom HVAC to the real need.

ENERGY REDUCTION:

FUTURE

ADAPTIVE (DEMAND BASED) CONTROL -

FUTURE CLEANROOM OPERATIONS WILL

BE SUPER-EFFICIENT

16


PARTICLE CONCENTRATION

Time – duration 1 production day

Limit: Grade C (in operation) / ISO 8

Limit: Grade B (in operation) / ISO 7


PARTICLE CONCENTRATION

Log Scale

Count (no of

particles / m3)

Limit: Grade B (in operation) / ISO 7

Limit: Grade C (in operation) / ISO 8

Time – duration 1 production day


CURRENT PRACTICE

Fixed Air Supply

Rate (ACR) Variable

Contamination

Levels

(#particles/m3)

ACR Classification Limit


• We don’t know the actual contamination level at any particular

time or location

• Most of the time particle generation rates are low, therefore air

flow is much higher than needed

• Fan energy accounts for 35-50% of the annual energy

consumption of a cleanroom

• As energy costs increase, cost of production increases

WHAT DOES IT MEAN?


HYPOTHESIS: CAN WE CONTROL TO A FIXED CONTAMINATION LEVEL?

Variable Air Supply

Rate (ACR) Fixed

Contamination

Levels

(#particles/m3)

New ACR

Classification Limit



• Static air change rate (without ICCS): PI controllers implemented in the BMS maintain the ACR for cleanrooms to steady state

• Dynamic particulate control (with ICCS): particle counter based MPC implemented in the PLC platform control the particle concentration dynamically.

• ICCS control setpoint: 20% of classification limit

• People with cleanroom gowning

23

RESULTS – STATIC VS. DYNAMIC CONTROL

0.2% 4.3%

0.1% 1.3% 0.7%

12.9%

0.8%

11.3%

0.0%

20.0%

40.0%

60.0%

80.0%

100.0%

120.0%

0.5um 5um 0.5um 5um

Grade C room Grade B room

Without ICCS With ICCS

Classification limit ICCS control setpoint

GMP EU Classification limit

Maximum particle concentration with and without ICCS (Grade C)

Percentage of

classification limit


RESULTS – ACR IN TEST CLEANROOMS

0

2

4

6

8

10

12

14

16

18

1 4 7

10

13

16

19

22

25

28

31

34

37

40

43

46

49

52

55

58

61

64

67

70

73

76

79

82

85

88

91

94

97

100

103

106

109

112

115

118

121

124

127

130

133

136

AC

R (

/hour)

Time (min)

Air Change Rate (ACR) with and without ICCS (Grade C)

Without ICCS With ICCS

Grade C room


• Particulate count maintained

under 20% of class limit

• 67% energy reduction

compared with static system.

RESULTS - ENERGY

32,938

10,906

-

5,000

10,000

15,000

20,000

25,000

30,000

35,000

Without ICCS With ICCSE

nerg

y (k

Wh)

Energy consumption per year

67% reduction

Static Dynamic


1. Cleanroom energy consumption can be reduced with no

significant impact to performance;

2. Higher classes are more energy intensive – but lower classes

consume more energy;

3. Performance of the cleanroom is critical - Air Change Rate is not;

4. Applicable reduction strategies should be considered on a case

by case basis;

5. Adaptive (demand based) control of cleanroom HVAC has huge

potential for cleanroom energy reduction globally.

SUMMARY

THANK YOU Any Questions?

Find out more at:

www.eeco2.com

Documents

CLEANROOM ENERGY REDUCTION - ISPE Boston€¦ · CLEANROOM ENERGY REDUCTION: POSSIBILITIES FOR NOW & IN THE ... The standard industry model for cleanroom design & operation has not