1

Integrated Design of Commercial Buildings for Primary Energy Efficiency: Contributions of CHP

Martha Krebs and James D. Freihaut at the

En Banc Hearing May 5, 2014

Drexel University, Philadelphia, PA

2

CHP Technical Potential for the Commercial Sector

191 294

1,189

2,030

2,838

1,892

337

Delaware

DC

Maryland

New Jersey

Pennsylvania

Virginia

West Virginia

3

• Reducing building energy use is a national priority (EPAct 2005)

• Despite ~50% improvement in equipment efficiency (since 1970s), building energy use has only declined by 15%

• Challenge: SMSCB* are diffuse (>95% of comm. bldgs.), ~half (>47%) of commercial building energy consumption, and has received little attention

Why SMSCB* Energy Efficiency is Challenging and Important

Residential Buildings

22%

*Small and Medium Sized Commercial Buildings (less than 250k square feet)

Based on data from NREL, DOE, and the National Trust for Historic Preservation

Annual Energy Use by Sector in USA

SMSCB*

Large Commercial Buildings

Commercial Buildings

18%

Industry 32%

Transportation 28%

Residential Buildings

22%

(focus of CBEI)

The CBEI Approach

•Develop cost-effective packages of technology solutions that have demonstrated energy savings

•Adapt solutions to the technical level of SMSCB owners and service providers who are engaged in planning and execution of demonstration efforts

•Engage with key stakeholders (retrofit industry, building owners, tenants, cities, regulators)

•Build on DOE innovations

5

Technology Systems and Market Efforts Are Interconnected and Iterative

National & Private

Sector Labs

Building Owners/

Operators/ Installers

City/State/ Local

Agencies

Private Financing

Solution Vendors

Nonprofits/ Knowledge

Transfer Entities

Utilities CBEI

Technology Integration

Market Needs

End Users Technology Developers

Enablers

6

The Challenge of Retrofitting Small and Medium Buildings

•Building Owners are inexperienced about energy efficiency.

•Energy Efficiency Best Practices are not easily available or tailored for this sector.

•Service Providers for this sector are not experienced for deep energy retrofits.

•Financing is difficult. •Tenant interests don’t match Owner/Operator interests.

7

Impact of Energy Efficient Buildings • A 50 percent reduction in buildings’ energy usage would

be equivalent to taking every passenger vehicle and small truck in the United States off the road.

• A 70 percent reduction in buildings’ energy usage is equivalent to eliminating the entire energy consumption of the U.S. transportation sector.

? WHY ? 84% of energy consumed in buildings is during the use of the building

DESIGN, CONTROL AND OPTIMIZATION OF WHOLE BUILDING SYSTEMS IS THE ONLY WAY TO GET THERE …

8

Principal Building Activity

Electricty EUI

(kBTU/ft2-yr) Fossil EUI

(kBTU/ft2-fr) λ thermal/elect

Education 24.7 54.6 2.211 Food Sales 163.9 49.6 0.303 Food Service 96 149.5 1.557 Health Care 76.6 163.8 2.138 Lodging 39.1 88.2 2.256 Mercantile and Service 35.5 40.9 1.152 Office 57.9 39.3 0.679 Public Assembly 35.9 77.8 2.167 Public Order and Safety 30.8 66.4 2.156 Religious Worship 8.8 28.6 3.250 Warehouse and Storage 17.1 21.2 1.240 Other 60.2 112 1.860 Vacant 5.2 16.3 3.135

Every Building Type Has a Specific Thermal/Electric Demand Ratio, λ D ,Signature

9

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0

λ D of Building

Theoretical All Thermal Building

η Primary Energy Utilization of Building

All Electric Building (Many Exist)

λ D Range of Most Commercial Buildings

Separate Heat and Power Commercial Buildings Efficiency Limited by Electric Generation, Transmission, Distribution Efficiency

10

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0

λ D of Building

All Thermal Building

Design Day Method Oversized HVAC Equipment Part load Inefficient Operation 95% of Time No Integrated Systems Design = No Coordination of Lighting, HVAC, Envelope Design & Operation No Dynamic Control of Building Subsystems

η Primary Energy Utilization of Building

All Electric Building

Separate Heat and Power Commercial Buildings Efficiency Limited by Electric Generation, Transmission, Distribution Efficiency

11

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

0.0 5.0 10.0 15.0 20.0

η Primary Energy Utilization of Building

λ D of Building

Combined Heat and Power Commercial Buildings Efficiency Overcomes Electric Generation, Transmission, Distribution Inefficiency

12

Thermal Load

Kw Load

24 hr Day

Conventional SHP Load Profiles

24 hr Day

Desired Load Profiles for CHP & Dynamic Controls Optimization

Increase Building Thermal Capacitance Controlled and Known Infiltration (Latent Load) Integrated Daylight and Lighting Controls Short Term Electric and Thermal Storage Reliable, Cost Effective Dynamic Controls

CBEI Integrated Design Paradigm Shift

Thermal Electric

13

24 hour cycle

Kw Demand

Thermal Demand

Prime Mover Kw , Thermal

Steady State Output

Prime Mover Recoverable

Thermal

Short Term Electrical Storage

Short Term Thermal Storage

Prime Mover Recoverable

Kwh

Innovation Needed in Short Term Storage Systems for General Applicability of CHP Design Paradigm

14

Background

15

PA Future CHP Technical Potential

Source: ICF International February 2013

(Current Commercial CHP is ~ 600 MW)

16

PA Commercial Tech Potential

Number of MW by SIC Code Total: 2,838 MW

Source: ICF International February 2013