# Presentation: 020698

## Energy Efficient Laboratories for the 21st Century:  Five Big Hits

**Energy Efficient Laboratories for the 21****st**** Century:  Five Big Hits**

- Dale Sartor, P.E.
- Group Leader, Applications Team
- 	Building Technologies DepartmentLawrence Berkeley National Laboratory
- Federal Environmental Symposium, June 4, 2008

## Lab Energy Intensity

**3 to 8 times as energy intensive as office buildings**

**Total Site Energy Use Intensity BTU/sf-yr ****for various laboratories in the Labs21 Benchmarking Database**

## Why Sustainability for Labs?

- Laboratories are very energy intensive
- 3 to 8 times as energy intensive as office buildings
- Substantial efficiency opportunities
- 30%-50% savings over standard practice
- Triple bottom line** **
- Reduce life cycle costs
- Improve workplace quality and safety
- Reduce environmental impact

## Labs21 Program

**A joint EPA/DOE-FEMP program to improve the environmental performance of U.S. laboratories**
- Optimize whole building efficiency on a life-cycle basis
- Assure occupant safety
- Minimize overall environmental impacts

## Labs21 Program Components

**Partnership Program**
- Draws together lab owners and designers committed to implementing high performance lab design.
- LBNL is a partner
**Training Program**
- Includes annual technical conference, training workshops, and other peer-to-peer opportunities.
**Tool Kit for Sustainable Design**
- Resources for owners, designers, and operators

## Core information resources
Design Guide
Case Studies 
Energy Benchmarking 
Best Practice Guides
Technical Bulletins 
Design process tools
Env. Performance Criteria 
Design Intent Tool 
Labs21 Process Manual 

***Core information resources***
- Design Guide
- Case Studies
- Energy Benchmarking
- Best Practice Guides
- Technical Bulletins
***Design process tools***
- Env. Performance Criteria
- Design Intent Tool
- Labs21 Process Manual

**Labs21 Toolkit**

**Notes:**
Questions for Design Team:
How active are you in Labs21?
What Labs21 tools do you use?

## Key Energy Efficiency Strategies for Labs	

## Lab Energy Use is Dominated by HVAC

**Ventilation is the largest component of energy consumption in most labs**
- % varies by lab type and location
**In some labs, 10-20% savings in ventilation is equivalent to total lighting energy use**

**Notes:**
Energy is the big environmental hit in Labs

Questions for Design Team:
What are the big energy “hits” in a lab, and how do you address them?

## Major Efficiency Strategies for Laboratories

**Ventilation Systems**
- Optimizing ventilation rates
- Minimize areas requiring high ventilation rates
- High performance fume hoods – VAV, low-flow
- Multi-stack exhaust plenum with staged exhaust fans
- Low-pressure drop design

**Heating and Cooling Systems**
- Energy recovery (latent and sensible)
- Right-sizing HVAC systems
- Systems that minimize or eliminate reheat
- Multiple cooling loops at different temperatures.
- High part-load heating and cooling efficiency
**Lighting Systems**
- Daylighting and controls
- High-efficiency electrical lighting systems
- Occupancy controls

## Five BIG HITS

**Scrutinize the air changes: Optimize ventilation rates**
**Tame the hoods: ****Compare exhaust device options **
**Get real with loads: ****Right-size HVAC systems**
**Just say no to re-heat: ****Minimize simultaneous heating and cooling**
**Drop the pressure drop: ****Use lower pressure-drop HVAC designs**

## #1  Scrutinize the Air Changes

***Air change rates have large peak and total cost impact***
**Don’t assume air changes are driven by thermal loads**
**What do you use as minimum air change rate (ACR)?**
- Why? Why? Why?
**When is ten or more air changes safe and six air changes (or less) not?**

**Notes:**
The minimum outside air change rate in the Foundry is 6 per hour – at the low end of the range, however, others are finding creative ways to safely reduce the rate.

Questions for Design Team:
What drives outside air change rates in your laboratory projects?
Is ten air changes safer than six?  Why?

## Scrutinize the Air Changes

**Options to consider**
- cfm/sqft rather than ACR
- Panic switch concept
- Cascading air from clean to dirty
- Setback ACR when lab is unoccupied
- Demand controlled ventilation (based on monitoring of hazards and odors)
- Control Banding (one rate doesn’t fit all)
- Modeling and simulation for optimization
**Ventilation effectiveness is more dependent on lab and HVAC design than air change rates (ACR)**
**High ACR can have a negative impact on containment devices**

**Notes:**
Question for Design Team:
How do you optimize the effectiveness of ventilation in labs and minimize its energy consumption?

## #2  Tame the Hoods

**#2****  Tame the Hoods**

***Fume hood Energy Consumption***

## Tame the Hoods

**Reduce the number and size of hoods**
**Restrict the sash opening**
**Use Two “speeds” occupied and un-occupied**
**Use variable air volume (VAV)**
**Consider high performance hoods **
**Say no to Auxiliary Air hoods**

**Notes:**
Hoods generally don’t drive the ventilation in the Foundry where restricted sash and VAV was utilized.

## #3  Drop the Pressure Drop

**Up to one half HVAC energy goes to fans**
**How low can you go?**

**Notes:**
Question for Design Team:
What role does duct sizing and configuration play in the architecture of your projects?

## Low Pressure Drop Design

**Notes:**
Question for Design Team:
What typical face velocities do you use in lab air handlers?

## Annual Energy Cost for Cleanroom Recirculation Fans

*Operating cost range for same cleanliness*

## Low Pressure-Drop Design Guidelines

| Component  | Standard | Good | Better |
| --- | --- | --- | --- |
| Air handler face velocity | 500 | 400 | 300 |
| Air Handler  | 2.5 in. w.g. | 1.5 in. w.g. | 0.75 in.w.g. |
| Heat Recovery Device  | 1.00 in. w.g. | 0.60 in. w.g.  | 0.35 in. w.g. |
| VAV Control Devices  | Constant Volume, N/A | Flow Measurement Devices, 0.60 - 0.30 in. w.g. | Pressure Differential Measurement and Control, 0.10 in. w.g. |
| Zone Temperature Control Coils  | 0.5 in. w.g. | 0.30 in. w.g. | 0.05 in. w.g. |
| Total Supply and Return Ductwork  | 4.0 in. w.g. | 2.25 in. w.g. | 1.2 in. w.g. |
| Exhaust Stack | 0.7” w.g. full design flow through entire exhaust system, Constant Volume | 0.7” w.g. full design flow through fan and stack only, VAV System with bypass | 0.75” w.g. averaging half the design flow, VAV System with multiple stacks |
| Noise Control (Silencers) | 1.0” w.g. | 0.25” w.g. | 0.0” w.g. |
| Total | 9.7” w.g. | 6.2” w.g. | 3.2” w.g. |
| Approximate W / CFM | 1.8 | 1.2 | 0.6 |

**Low Pressure-Drop Design Guidelines**

**Notes:**
Note: Foundry was designed for 7.5” and is operating at 1⁄2 that (3”-4”) due to VAV. 

Question for Design Team:
Do you typically use silencers in your lab duct design?  If not, how do you assure quiet operation?

## Labs21 Benchmarking Tool – Vent. W/cfm

**Labs21 Benchmarking Tool – Vent. W/cfm**

***standard***

***good***

***better***

- Standard, good, better benchmarks as defined in
- “How-low Can You go: Low-Pressure Drop Laboratory Design”  by Dale Sartor and John Weale

**Notes:**
Note that these benchmarks are 1⁄2 in previous table because it is based on just supply cfm, not total supply and exhaust

Question for Design Team:
What typical W/cfm or overall design pressure drop would you design to?

## #4  Get Real with Plug Loads

**Save capital cost and operating cost**
**Measure actual loads in similar labs**
**Design for high part- load efficiency**
- Modular design approaches
**Plug load diversity in labs increases reheat**

**Notes:**
The Foundry project measured actual plug loads in several existing laboratories and significantly reduced capital and operating costs by “right sizing.”  Further a modular heating plant at the Foundry will allow for efficient part load efficiency.  Although the chiller plant includes a variable speed drive, the average load is low and it will be difficult to run the chillers efficiently.

Question for design team:
What plug loads do you typically assume in labs of this sort (watts per square foot)?  

## Measured vs. Design – UC Davis Case Study

**Significant over-sizing not unusual**

## Measured Plug loads in Labs

**Sandia PETL Lab**
- Designed for 6 W/nsf;
- Metered data: 1.8 W/nsf (avg.), 2.7 W/nsf (peak)
**Fred Hutch Cancer Research Center**
- Phase 1 designed for 15-30 W/nsf
- Phase 2 reduced design to 8 W/nsf based on Phase 1 experience
**Pharmacia **
- Designed for 12 W/nsf
- Metered data: 2.7 W/nsf

## Benefits of Right-sizing at LBNL-MFL

**$2.5 million first cost savings for right-sizing HVAC systems**
- Based on measured data from comparable labs
**LEED Silver (expected)**
- Rightsizing savings allowed additional green features with 4% cost savings over baseline.

*The Molecular Foundry*
*Lawrence Berkeley National Laboratory*

## #5  Just Say No to Reheat

**Reheat (simultaneous heating and cooling) causes major energy use in labs**
- High-load areas require lower supply air temperature, so reheat occurs in other spaces

**Notes:**
Simultaneous heating and cooling is more problematic in labs, where variations of internal loads can be enormous
A single zone requiring cooling can create a larger heating and cooling load for the other zones
At peak design conditions (hottest outside air), all the supply air is cooled to 55 degrees or less, and the volume of air is increased to the warm zones, thus significantly increasing the size of the cooling plant
Most zones require reheat even at peak outdoor temperature conditions
Most engineers underestimate the impact/waste of reheat by assuming that their plug loads are constant
Controls often fall out of “calibration” and energy waste increases

## System Alternatives to Minimize Reheat 

**Dual-duct systems**
**Ventilation air with zone coils**
**Ventilation air with fan coils**
**Ventilation air with radiant cooling**
**Ventilation air with inductive cooling coils**

**Notes:**
Separating ventilation and cooling systems significantly reduces the size of the ventilation system and the chiller plant (often by a factor of 2)
When all costs and savings are considered these systems are generally no more expensive than VAV reheat

The Foundry used VAV reheat. 

Question for Design Team:
What alternatives to VAV reheat have you used in labs? What was the cost implication?

## For More Information

- 	     **http://www.labs21century.gov **

***Contacts******:****** ***

**For More Information**

- Dale Sartor, PELawrence Berkeley National LaboratoryPhone: 510 486-5988E-mail: dasartor@lbl.gov

## Supplemental SlidesLabs21 Environmental Performance Criteria(Beyond LEED)	

## Labs21 Environmental Performance Criteria (EPC)

**Rating system specifically for laboratories**
**Leverages and builds on LEED**
- Modifications and additions to improve applicability to labs
**Developed with over 40 industry volunteers**
**Used on many lab projects**
- Specified in UC Regents policy
- Used on Molecular Foundry at LBNL

## LEED and EPC

**LEED is a USGBC product**
**EPC is a Labs21 product**
- No certification
**USGBC is developing a LEED Application Guide for Laboratories (LEED-AGL) “LEED for Labs”**
- Based on the EPC
**Both tools are useful, but beware of “point-chasing”**
- Avoid design by checklist

**Notes:**
Questions for Design Team:
Are you familiar with the Labs21 EPC?
How does it compare to LEED and have you used it?

## LEED and EPC

## Labs21 EPC - Sustainable Sites

**1. Minimize impact of air effluents**
- Use mathematical modeling, physical modeling and/or post-construction testing and certification to prove compliance
**2. Prevent release to sanitary sewer**
- Prevent releases of hazardous chemicals and other pollutants to sanitary sewer, using containment and engineering controls

*Source: Cermak Peterka Petersen*

## Labs21 EPC - Water Efficiency

**Labs21 EPC - Water Efficiency**

**Prerequisite: Avoid one-pass water for cooling**
**Credits: Reduce process water and process wastewater**
**Strategies:**
- Use closed loop cooling
- Reduce, reuse, recycle.
- Flow control – turn off when not in use
- Reuse last rinse for first rinse of next cycle
- Treat process wastewater for down-cycled use in cooling towers, etc.

*Nidus Center. Source: Hedrick-Blessing*

## Labs21 EPC – Indoor Environmental Quality

**Prerequisite: Minimum requirements**
- Meet ANSI Z 9.5
**Credits for user health ****and safety**
- 1. Optimize indoor airflow based on CFD or physical modeling.
- 2. Commission all fume hoods per ASHRAE 110, with performance rating of 4.0 AI 0.1
- 3. Self-identifying and fail-safe alarm systems

*Source: RWDI*

## Sustainability Begins with  the Program

**Global Ecology Center, Stanford**
- High heat-load equipment moved to un-cooled warehouse; Most temperature-sensitive equipment in separate room, reducing the area with tight temperature control requirement
- 41% efficiency savings + 17% program savings = 58% total savings (vs. CA Title 24)

*Source: EHDD Architecture*

*Source: Timothy Hursley*

**Bren School, UC Santa Barbara**
- Office and classroom wing  separated out from lab wing to allow for full natural ventilation.
- LEED Platinum rating