integrated design of commercial buildings for primary ... · 1 integrated design of commercial...
TRANSCRIPT
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
15
PA Future CHP Technical Potential
Source: ICF International February 2013
(Current Commercial CHP is ~ 600 MW)