Efficient Laboratory Hoods

Summary

Efficient Laboratory Hoods

Laboratory Hoods: Lab21 Efficiency Features vs. Conventional

A package of lab hood efficiency measures including heat recovery and automatic sash positioning.

Synopsis:

Energy use per square foot in a modern laboratory can be five to ten times that of a typical office building. Because laboratories use significant energy and their design can influence energy use, a public-private partnership called Labs for the 21st Century was formed in 2002 to provide design guidelines for efficient lab operations. Many of these guidelines focus on improving laboratory ventilation systems, especially for fume hoods. This information assists laboratory designers and operators and encourages the building of high-performance labs.

Efficient laboratory fume hoods could employ a package of high-performance technologies to minimize energy consumption. The package would include high-efficiency variable speed fans and heat recovery to recover some of the energy in the conditioned air that is being drawn from the laboratory space around the hood. Automatic sash positioning could also be implemented with an occupancy sensor automatically closing the sash when no occupants are detected and the fume hood is not is use.

Depending on the size and needs of the lab, the Lab21 Best Practice guidelines suggest a variety of strategies, including manifolding hood systems for increased efficiency. With this strategy, multiple hoods can be ganged together in the same ducting system so that two variable speed fans can provide ventilation for all of the hoods. The same fans can also supply exhaust ventilation for general laboratory space. Still under development are technologies that will provide acceptable fume capture while dramatically reducing required face velocities and air flow requirements. (http://www.labs21century.gov/pdf/lowenergy_508.pdf, Aug. 2008)

Energy Savings: 30%

Energy Savings Rating: Comprehensive Analysis What's this?

Level	Status	Description
1	Concept not validated	Claims of energy savings may not be credible due to lack of documentation or validation by unbiased experts.
2	Concept validated:	An unbiased expert has validated efficiency concepts through technical review and calculations based on engineering principles.
3	Limited assessment	An unbiased expert has measured technology characteristics and factors of energy use through one or more tests in typical applications with a clear baseline.
4	Extensive assessment	Additional testing in relevant applications and environments has increased knowledge of performance across a broad range of products, applications, and system conditions.
5	Comprehensive analysis	Results of lab and field tests have been used to develop methods for reliable prediction of performance across the range of intended applications.
6	Approved measure	Protocols for technology application are established and approved.

Details

Efficient Laboratory Hoods

Laboratory Hoods: Lab21 Efficiency Features vs. Conventional

A package of lab hood efficiency measures including heat recovery and automatic sash positioning.

Item ID: 185

Sector: Commercial, Industrial

Energy System: HVAC--Other HVAC Systems

Technical Advisory Group: 2009 HVAC TAG (#2)

Synopsis:

Baseline Example:

Baseline Description: Lab Facility with conventional design approaches
Baseline Energy Use: 140 kWh per year per square foot

Comments:

Labs are energy intensive facilities. Labs21 estimates labs use 5-10 times more energy than a typical office building (NREL, 2000). The 2009 Commercial Building Stock Assessment gives the actual electrical building energy use index (EUI) for various types of heating and cooling systems (Table D-EA5, ( NEEA, 12/21/2009)). Office buildings with electric heating and cooling have an EUI of 20.1 kWh/sf/year. Those with electric cooling have an EUI of 14.8 kWh/sf/year. For a lab facility, assume 140 kWh/sf/year, which is approximately 10 times the office building case with no electric heating and 7 times the case with electric heating and cooling.

Manufacturer's Energy Savings Claims: Currently no data available.

Best Estimate of Energy Savings:

"Typical" Savings: 30%
Low and High Energy Savings: 20% to 50%
Energy Savings Reliability: 5 - Comprehensive Analysis

Comments:

Savings will varying depending on the application and the range of design strategies incorporated. The Lab21 document makes a projection of 30% energy savings.

Energy Use of Emerging Technology:

98 kWh per square foot per year What's this?

Energy Use of an Emerging Technology is based upon the following algorithm.

Baseline Energy Use - (Baseline Energy Use * Best Estimate of Energy Savings (either Typical savings OR the high range of savings.))

Technical Potential:
Units: square foot
Potential number of units replaced by this technology: 10,106,200
Comments:

This is a design strategy that applies to new construction. Laboratories are a small fraction of commercial and industrial floor space. For the purposes of this analysis assume that approximately 1% of new commercial construction and major renovations will consist of laboratory space. CBSA data can be used to make projections of commercial building square footage ( NEEA, 01/1/2014). Using a 1% annual growth rate and 2% replacement rate (3% total), we estimate that over 10 years new construction and major renovations will be 34% of existing commercial square footage: 3,118,000,000 * 0.34 = 1,060,120,000 sf. One percent of this is 10,106,200 sf.

Regional Technical Potential:
0.42 TWh per year
48 aMW
What's this?

Regional Technical Potential of an Emerging Technology is calculated as follows:

Baseline Energy Use * Estimate of Energy Savings (either Typical savings OR the high range of savings) * Technical Potential (potential number of units replaced by the Emerging Technology)

First Cost: Currently no data available.

Cost Effectiveness:

Simple payback, new construction (years): N/A

Simple payback, retrofit (years): N/A

What's this?

Cost Effectiveness is calculated using baseline energy use, best estimate of typical energy savings, and first cost. It does not account for factors such as impacts on O&M costs (which could be significant if product life is greatly extended) or savings of non-electric fuels such as natural gas. Actual overall cost effectiveness could be significantly different based on these other factors.

Reference and Citations:

NEEA, 01/01/2014. Total Pacific Northwest Building Stock Based on Preliminary Numbers from the 2013 Update to the CBSA
Northwest Energy Efficiency Alliance

CADMUS, 12/21/2009. Northwest Commercial Building Stock Assessment (CBSA): Final Report
Prepared by the CADMUS Group for the Northwest Energy Efficiency Alliance

NREL, 10/31/2000. Laboratories for the 21st Century: An Introduction to Low-Energy Design
National Renewable Energy Laboratory

LBNL, 08/07/2007. Laboratories for the 21st Century: Best Practice Guide – Manifolding Laboratory Exhaust Systems
Lawrence Berkeley National Laboratory

Rank & Scores

Efficient Laboratory Hoods

2009 HVAC TAG (#2)

Technical Advisory Group: 2009 HVAC TAG (#2)
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