Iowa Public Building Benchmarking Introduction to the Public - - PowerPoint PPT Presentation

▶
iowa public building benchmarking
SMART_READER_LITE
LIVE PREVIEW

Iowa Public Building Benchmarking Introduction to the Public - - PowerPoint PPT Presentation

Mar 07, 2023 46 likes •252 views

Iowa Public Building Benchmarking Introduction to the Public Website Presented by Xiaohui Joe Zhou, PhD, PE, Iowa Energy Center Outline Introduction of Building Energy Benchmarking Basic Concepts and Terminologies Iowa Public

slide-1
SLIDE 1

Iowa Public Building Benchmarking

Introduction to the Public Website

Presented by Xiaohui “Joe” Zhou, PhD, PE, Iowa Energy Center

slide-2
SLIDE 2

Outline

  • Introduction of Building Energy Benchmarking
  • Basic Concepts and Terminologies
  • Iowa Public Building Energy Benchmarking

Public Site

  • How to Interpret the Results
slide-3
SLIDE 3

Introduction - Benchmarking

  • Energy Benchmarking

 For cars we use:

Miles per gallon

 For lighting efficiency (more accurately luminous efficacy):

Lumens per Watt

 For buildings we use Energy Use Intensity (EUI):

kBTU per square foot per year

slide-4
SLIDE 4

Introduction - Benchmarking

  • Building Energy Benchmarking

Building Energy Benchmarking Methods

  • Compare with similar buildings, within a portfolio, or nationally?
  • Compare to self in a baseline year?
  • Compare to an energy code-compliant building of the same size,

type, and function?

Iowa Public Building Energy Benchmarking

  • Does all three methods
slide-5
SLIDE 5

 Energy Use Intensity (EUI):

  • Total energy of all fuel sources consumed by the building in one

year, converted to kBTU and divided by the total gross floor area

  • f the building
  • Unit: kBTU/SF/yr;
  • BTU: British Thermal Unit. A traditional unit of energy. A BTU

represents the amount of energy needed to cool or heat one pound of water by one degree Fahrenheit.

  • 1 kBTU = 1000 BTU = 293 Watt-Hour = 0.293 kWH
  • 1 kWH = 3.412 kBTU

Introduction - Terminology

slide-6
SLIDE 6

Introduction - Terminology

City Chicago Denver Minneapolis Climate Zone 5A 5B 6A Large Office 43 36 46 Medium Office 48 41 54 Small Office 51 45 57 Warehouse 24 23 29 Stand-alone Retail 81 69 93 Strip Mall 85 72 99 Primary School 65 58 75 Secondary School 76 64 89 Supermarket 195 179 208 Quick Service Restaurant 657 604 713 Full Service Restaurant 527 481 570 Hospital 148 130 153 Outpatient Facility 271 271 280 Small Hotel 80 74 87 Large Hotel 138 131 150 Mid-Rise Apartment 47 41 54

  • However, EUI alone is

not a reliable indicator for building energy

  • performance. Many

factors have impact:

  • Weather
  • Building type
  • Building function
  • Occupancy

* DOE Commercial Building Benchmarks – New Construction. EUIs (kBTU/sf/yr). October 2009

slide-7
SLIDE 7

 Benchmarking EUI

  • Building Energy Codes: minimum requirements for energy efficient

design and construction of new and retrofit buildings

  • Benchmarking EUI: Predicted annual Energy Use using simulation based
  • n the energy-code compliant building with the same size, space types,
  • ccupancy, and local weather conditions

 Benchmarking Index Ratio

  • Index Ratio = Actual EUI / Benchmarking EUI
  • Smaller the better. e.g., a 0.75 number means the building uses 25%

less energy than an energy-code compliant building. A 1.5 number means the building used 50% more.

Introduction - Terminology

slide-8
SLIDE 8
  • A building may have its own meters thus 1 site = 1 building, however…
  • Some buildings share 1 or more meters with other buildings, thus 1 site =

various buildings

  • Each participating organization may have one or more sites

E G G

Site

E G

Site

Introduction - Basic Concept

G: Gas meter; E: Electric meter

slide-9
SLIDE 9

Iowa Public Building Benchmarking

1200 buildings (Phase I) 600 buildings (Phase II so far)

slide-10
SLIDE 10

Introduction – Public Site

Sector Selection Menu Result Window Result Selection Tabs Result Map Window Expand Windows

slide-11
SLIDE 11

 Sectors

  • 1: All Sectors
  • 2: Cities (default)
  • 3: Counties
  • 4: Public Schools
  • 5: Community Colleges
  • 6: Higher Education
  • 7: State Agencies

How to Interpret the Results

Organizations within the same sector may be more comparable.

slide-12
SLIDE 12

 Main Table – by EUI

How to Interpret the Results

Rank or sort by average EUI for all completed buildings

slide-13
SLIDE 13

 Main Table – by Benchmark

  • Benchmark Star Ratings correspond to Index Ratio ranges

How to Interpret the Results

Rank or sort by Benchmarking Index Ratio

slide-14
SLIDE 14

 Main Table – by Energy $/SF

How to Interpret the Results

Rank or sort by average unit energy cost for all completed buildings

slide-15
SLIDE 15

 Main Table – by Potential Savings

  • For any organization that has benchmarking ratio > 0.85

How to Interpret the Results

MMBTU: 1 Million BTU = 1,000,000 BTU

Rank or sort by energy savings (MMBtu/yr) or cost savings ($/yr) for all completed buildings

slide-16
SLIDE 16

 Main Table – by Freshness of Data

How to Interpret the Results

Rank or sort by the “freshness” of utility data

slide-17
SLIDE 17

 Map – sorted by EUI

How to Interpret the Results

Result summary

slide-18
SLIDE 18

 Help

How to Interpret the Results

slide-19
SLIDE 19

 Summary

  • In reviewing an organization’s results, first look at benchmarking

index ratio (and therefore benchmarking five-star rating)

  • Then look at potential energy savings and cost savings
  • Look at energy $/SF
  • Freshness of data
  • Compare within the same sector

How to Interpret the Results

Note: This website is designed to inform the public about how Iowa public buildings perform and for organizations to make better informed decisions when doing energy efficiency work. All participating organizations have voluntarily started the process to measure their buildings’ performances. The Iowa public building benchmarking team fully appreciates their participation and co-operation.

slide-20
SLIDE 20

More Questions?

Xiaohui “Joe” Zhou, xhzhou@iastate.edu Katie Schmitt, katies@twgi.com