Operations and Maintenance Essentials

Operations and Maintenance Essentials

Green Professional Building Skills Training

To understand:

A.How to measure the performance of your building

B.The role of the building envelope and how to improve its impact on the interior environment

C.Ways to improve and minimize water use

D.How heating and cooling systems work and how they can be improved

COURSE OBJECTIVES

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GPRO Certificate Holders

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OPERATIONS AND MAINTENANCE IN GREEN BUILDING

LEED Gold Building, NY

A green building is designed, constructed and maintained to minimize adverse environmental impacts and to reduce energy consumption, while contributing to the health and productivity of its occupants.

A key component is consideration of the building's impacts and performance over its entire lifespan.

A Green Building

Sustainability is about using less by using smart

U.S. Potable Water Used in Buildings

U.S. Energy Used in Buildings

40% 12%

Why Sustainability in Building Operations Matters Page 2

All these complex systems work together, whether they are working well or not.

Why Sustainability in Building Operations Matters Page 3-4

The Whole-Building Approach

• Observe building systems• Monitor operating systems• Measure electric, water, and fuel use• Assess problems (high bills, tenant complaints)• Tune existing equipment• Install new green equipment• Auditing and Retro-Commissioning

The Role of Building Superintendents, Managers, and Engineers

The Role of Building Superintendents, Managers, and Engineers Page 5

TEST YOURSELF:

1. Why does sustainability in building operations and maintenance matter?

2. Why use a "whole-building" approach when thinking about operation of a building's facilities?

3. Give an example of how the operation of one facility system in a building affects another of the building's systems.

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2 BUILDING PERFORMANCE METRICS

Water Meter

• Gallon (gal): volume• Gallon per minute (gpm): fluid flow• Cubic feet (cf) and Hundred cubic

feet (HCF or CCF): large volumes

How Water Usage is Measured

How Water and Energy Usage is Measured Page 6

• 1 cubic foot (cf) = 7.48 gal• 1 HCF = 748 gal

Water Bill Analysis


Electric Power = a rate, measured in Watts (W)• 1 kilowatt (kW) = 1,000 W• 1 megawatt (MW) = 1,000 kW

= 1,000,000 W

How Electric Power is Measured

High-voltage Power Lines


Electric energy = an amount, measured in kilowatt-hours (kWh)•1 kilowatt (1,000 W) x 1 hour = 1 kWh •100 watts (100 W) x 10 hours = 1,000 watt-hours (Wh) or 1 kWh

How Electric Consumption is Measured


Electric Meter

• Maximum power drawn during some time period, usually a month.

• Measured in kilowatts (kW)

Blackout, Eastern U.S. August 17, 2003

Peak Demand


• Demand charges can be a substantial part of your utility bill.

Some measures can reduce demand load AND consumption.

Before Repair

After Repair

Hourly Electric Load Data


• Electricity in kWh• Gas in therms• Steam in Mlb• Oil in gallons

How Fuel Consumption is Measured

Meters


Fuel Type Energy Content

Natural Gas 1,030 Btu / cf

Propane (liquid) 92,500 Btu / gal

Propane (gas) 2,500 Btu / cf

#2 Oil 138,500 Btu / gal

#4 Oil 145,000 Btu / gal

#6 Oil 150,000 Btu / gal

Steam (@ 212°F) 970 Btu / lb

Electric Heat 3,413 Btu / kWh

1 therm = 100,000 Btu, or the energy equivalent of burning 97 cf of natural gas.

How to Compare Different Heating Fuels


• Total amount of energy delivered to a building =

Fuel use (Btu) + electricity use (kWh converted to Btu)

• To convert electric energy to heat units:

Use 3,413 Btu/kWh

Site Energy


EXAMPLE 1:SITE ENERGYQUESTION: A building consumes 500,000 ft3 of gas and 200,000 kWh of electricity per year.

Gas energy content is 1,030 Btu/ft3. Electric energy content is 3,413 Btu/kWh.

What is the site energy?


EXAMPLE 1:SITE ENERGYANSWER: The site energy is the sum of the energy content of the gas and electricity used:

SiteE = 500,000 ft3/year x 1,030 Btu/ft3 (Gas)+ 200,000 kWh/year x 3,413 Btu/kWh (Electricity)

515,000,000 Btu/year + 682,600,000 Btu/year = 1,197,600,000 Btu/year or 1,198 MMBtu/year (each "M" means 1,000, so "MM" means one million)


The amount of energy used to generate electricity (which will be used by a building).

To convert electric energy to source energy:

Use 11,400 Btu/kWh

Source Energy

Useful electrical energy is only 1/3rd of source energy

How Water and Energy Usage is Measured Pages 9-10

EXAMPLE 2:SOURCE ENERGYQUESTION: What is the source energy of the building in Example 1?

The conversion value of the electric energy to source energy is 11,400 Btu/kWh.


EXAMPLE 2:SOURCE ENERGYANSWER: The source energy is the fuel delivered to the building added to the fuel used at the power plant to generate the electrical energy used in the building:

SourceE =

(500,000 ft3/year x 1,030 Btu/ft3) + (200,000 kWh/year x 11,400 Btu/kWh) =

515,000,000 Btu/year + 2,280,000,000 Btu/year = 2,795,000,000 Btu/year or 2,795 MMBtu/year


COMPARE:SITE ENERGY vs. SOURCE ENERGY

SiteE = 1,198 MMBtu/year SourceE = 2,795 MMBtu/year


Carbon Footprint

Carbon footprint from electricity generation varies dramatically depending on the fuel source.

U.S. electricity generation by type of energy in 2009


POP QUIZ:

What is the most expensive fuel?

POP QUIZ:Fuel Type (unit)

Cost /unit

Btu /unit

Cost / million Btu

Natural Gas (mcf) $11.34 1,030,000 $11.01

Propane (gallons) $1.86 92,500 $20.10

#2 oil (gallons) $2.69 138,500 $19.40

#6 oil (gallons) $2.30 150,000 $15.30

Steam (lb) $.024 970 $24.70

Electricity (kWh) $0.110 3,413 $32.20

Data for Dec 2010-Jan 2011 updated April 2011

EXERCISE QUESTION:

What factors affect your energy bills?

• Consumption (kWh)

• Demand (kW)

• Supply and Delivery charges may be on separate bills (both have consumption and demand charges)

Electricity Bill Analysis

Water and Energy Bill Analysis Page 10-11

Benchmarking is an important component of any energy management program because it helps you establish a baseline of energy or water use.

Energy Use Intensity (EUI)•The most common measure for energy benchmarking •Represents the total fuel burned and electricity consumed on a per-square-foot basis, per year•Typically reported as source energy

Benchmarking: Determining Water and Energy-Use Efficiency

Benchmarking: Determining Water and Energy-Use Efficiency Page 12

Source EUI

Can be determined for different energy sources by following these steps:

1.Convert energy sources to Btu (see conversion chart 2.6 on page 8 in your manual)

2.Add up all Btu from all energy sources to find the total Btu used in one year (= source energy/year)

3.Divide the source energy by the building's habitable floor space (= source EUI in Btu/sf/year)


What is the source EUI of the building we looked at in the section on site energy and source energy? It's useful floor area is 23,000 sf.

Benchmarking: Determining Water and Energy-Use Efficiency 12

EXAMPLE 3:SOURCE EUI

We found the source energy to be 2,795 MMBtu/year so:

Source EUI = 2,795,000,000 Btu/yr23,000 sf

= 121,522 Btu/sf/year

Benchmarking: Determining Water and Energy-Use Efficiency 12

EXAMPLE 3:SOURCE EUI

Portfolio Manager is EPA's tool to compare buildings to each other: https://www.energystar.gov/istar/pmpam/

Tools for Energy and Water-Use Efficiency


https://www.energystar.gov/istar/pmpam/

What About the Weather?

What About the Weather Page 13-14

Building performance is directly affected by weather.

The more extreme temperatures are, the harder a building's systems will work to keep its occupants comfortable, which will use more energy.

A Heating Degree Day (HDD) is a measure used to compare the severity of winter temperatures.

• Help us estimate the amount of fuel used for heating in a winter season

• Compare buildings in different climates

To calculate the annual HDD:

1. Find average daily temperature

2. Subtract from 65ºF

3. Add all HDDs for entire season

Heating Degree Days

What About the Weather Page 13-14

CLASSROOM EXERCISE:Day's High

TemperatureDay's Low

TemperatureAverage

TemperatureHDD

40 20 30 35

15 -5

70 50

75 65

What About the Weather? Page 13

Heating Energy Intensity (HEI) = Btu / sf / HDD• Btu = Total energy used for heating per year• sf = Area of entire building (in square feet)• HDD = Heating Degree Day

Heating Energy Index

Heating Energy Index Page 14-15

Calculating Btu

HEI = Btu / sf / HDD

1.Add up all fuel used for the year

2.Subtract the amount used for domestic hot water

3.Multiply by the Btu conversion for each type of fuel

Heating Energy Index Page 15

Calculating Area


1.Measure the floor space of the entire building in square feet

2.Include the basement spaces if they are conditioned

What About the Weather? Page 15

Calculating Heating Degree Days


1.Take the average daily temperature

2.Subtracting it from 65° F (example: For a day with a high of 40° F and a low of 20° F, the average would be 30°F, HDD for that day = 35).

3.Add heating degree days up for an entire season

Heating Energy Index Page 15

GROUP EXERCISE:

See Classroom Exercise #1 on page 89 of your manual:

Calculate the heating energy index (HEI)for the sample building.

Page 82

TEST YOURSELF:1. When would you measure water by cubic feet rather

than by gallons?

2. Why is it important to measure energy and water consumption?

3. What is benchmarking and how does it help manage energy and water consumption?

4. Why pay close attention to water and energy bills? What is an example of something that could cause a jump in your building's fuel bill?

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3 THE BUILDING ENVELOPE

The Function of the Building Envelope

The Function of the Building Envelope Page 16

WET ROOF INSULATION LEAKS HEAT

AIR INFILTRATION BETWEEN DOUBLE-HUNG WINDOW SASHES

MISSING INSULATION AT SPANDREL ALLOWS HEAT TO ESCAPE

WARM AIR ESCAPES THROUGH LOUVERS AT TOP OF ELEVATOR SHAFT

MISSING WALL INSULATION ALLOWS HEAT TO ESCAPE

Three mechanisms of heat transfer:

• Conduction• Convection• Radiation

Heat Transfer

Heat Transfer Pages 16-17

• Air is a poor conductor of heat, especially if it can't move. This makes it a good insulator.

• Insulation is effective because it contains tiny pockets of air, which slow heat flow.

• Minimizing heat flow reduces the energy demands on equipment, operating costs, and environmental impact.

Managing Conductive Heat Transfer


R-Value•Measure of thermal resistance•Expressed as heat flow per inch•Add up all the materials in the building assembly to get total R-Value•Insulation is only as good as the air sealing around it!

Thermal Resistance: R-Value


Applying soy polyurethane spray-on foam

• Batts• Boards / Rigid• Blown-in • Spray-on foam• Pipe


Which Insulation is Right for You?

• R-value comes from fluffiness• Air seal• Can have vapor barrier attached (foil face) on side that is

warm in winter• Don't compress (Always cut around obstructions)

Batts


Insulation Batts Infrared Image: Compressed Insulation

• Standard thicknesses ½" to 6"• Easy to install• High R-Value/inch• Must be air sealed

Insulation Boards

Heat Transfer Page 19


• Loose fill or dense-pack• Can also act as air seal

Blown-In

Blown-in cellulose insulation

• Soy based• Acts as an air seal• Needs to be

professionally installed

• High R-Value/inch

Spray Foam


Applying spray-on foam

Install pipe insulation everywhere!

Pipe Insulation


Polyethylene pipe insulation Fiberglass pipe insulation

• Minimize air infiltration through the envelope for energy efficiency.

• But maintain adequate ventilation to preserve indoor air quality.

Air Barrier Integrity

Air Barrier Integrity Page 20

A majority of a building's heat loss can be traced to air leakage.

Typical Air Leakage in a Home


Wind Effect Stack Effect Mechanical Ventilation

Air Movement in Buildings

Air Barrier Integrity Pages 20-21

Isolate spaces to prevent tobacco, cooking odors or air contaminants (from labs and parking garages) from entering occupied spaces.

Compartmentalization


• Seal and caulk wall penetrations at doors and windows

• Monitor temperature in winter and summer to prevent overheating or overcooling

• Seal wall between garage and occupied spaces to prevent CO infiltration

• Ensure air louvers are unobstructed

• Schedule cleaning and testing of ventilation shafts

• Provide flashings at parapets, window sills and any other penetrations to prevent water infiltration

• Weatherstrip all exterior doors

Air Barrier Integrity

Air Barrier Integrity Pages 21-22

Condensation Control Page 22

• Bulk Water (leaks)

• Condensation

• Vapor

How Water Enters Buildings

Leak at Exterior Wall

In a heating climate, install a vapor barrier on the warm side of the wall in winter.

Condensation Control: Vapor Barrier

Condensation Control Pages 22-23

A sling psychrometer measures relative humidity.


DRY BULB TEMP (˚C)

WET BULB TEMP (˚C)

RELATIVEHUMIDITY(curves)

DEW POINT(100% saturation)

Psychrometric Chart


POP QUIZ:

If the relative humidity in this room is 60%, and we raise the temperature, what happens to the relative humidity?

POP QUIZ:

As Temperature goes up

Relative Humidity goes down

Efflorescence on a brick wall

• Routine visual inspections

• Monitor renovation work

• Log tenant complaints

• Watch for increased heating or cooling demand

• Identify water leaks and repair

Addressing Envelope Problems

Addressing Envelope Problems: Options for Building Managers Page 23

TEST YOURSELF:1. What is the purpose of the building envelope and why is it

important that it works effectively?

2. What are the three types of heat transfer and how does the building envelope control them?

3. Explain the stack effect and two methods used to control it.

4. Describe three things building managers can do to maintain air barrier integrity in a building.

5. Describe how to prevent condensation of water in walls.

6. Describe three things you could see in your building that would indicate the building envelope is not functioning correctly.

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4 WATER USE

Reading the Meter

Consumption is measured in cubic feet (CCF or HCF used for 100 cubic feet)

Sample Reading 1

Single Dial Water Meter

Sample Reading 2

Compound High-Flow and Low-flow meter

Tracking Water Use

Tracking Water Use Page 24-25

SAMPLE READING 1:A 6-unit apartment building has 12 people living in it. The building has a single-dial water meter. The water rate is $4.27 per HCF.

Meter Reading January 1: 001123 cf

Meter Reading March 31: 011623 cf

Amount of water used in 3 months:

011623__- 001123__

10,500 cf

10,500 cf100

= 105 HCF

Cost of water used:

105 HCF @ $4.27/HCF = $448.35

Tracking Water Use Page 25

SAMPLE READING 1:Cost per apartment per quarter:

$448.356 apts.

= $74.73/apt.

Water used (in gallons): (Remember: 1 HCF = 748 gallons)

105 HCF x 748 gal/HCF = 78,540 gal

Cost per apartment per year (at this rate):

$74.73 x 4 = $298.92/apt./year

Gallons per person per day:

78,540 gal / 90 / 12 people = 73 gal/person/day


SAMPLE READING 2:A 30-unit apartment building is served by a compound meter that has a 2" (high-flow) meter and a ¾" (low-flow) meter.


"Amount of water used" equals high plus low flows:105 HCF + 400 HCF = 505 HCF

SAMPLE READING 2:Cost of water used:505 HCF @ $4.27/HCF = $2,156.35

Cost per apartment per quarter:$2,156.35 / 30 apts. = $71.88/apt.

Cost per apartment per year (at this rate):$71.88 x 4 = $287.52/apt./year

Water used (in gallons):505 HCF x 748 gallons/HCF = 377,740 gallons

Gallons per apartment per day:377,740 gal / 90 days / 30 apt. = 140 gallons/apt./day


• Log daily or weekly water consumption

• Logs will help detect hidden leaks sooner and help you understand patterns of usage

Water Use Logging

Water Use Reduction Practices Page 26

Indications of Leakage:•Condensation on toilet bowl: running flushometers•Corrosion on fixtures: dripping faucets

Monitor with:•Building water systems•Daily rounds•Drip gauges•Dye tablets•Moisture meters•Infrared cameras

Common Areas of Water Leakage


Ask occupants to:•Report leaks•Use low-flow fixtures•Purchase ENERGY STAR appliances and WaterSense fixtures•Turn off water when possible •Run washing machines and dishwashers only with full loads

Educate Occupants: Reduce Water Use

Water Use Reduction Practices Page 26-27

Water Broom

Instead of using a typical hose, try these alternatives:

Alternatives to Sidewalk Washing


• Sweeping with a dry broom

• Using a water broom

• Waiting for rainstorms to wash sidewalks naturally

Make sure to check mechanical system components for leaks:

•Excessive use of make-up water in boilers?

•Malfunctions in cooling towers?

•Wasted water in condensate tanks?

•Lost water in closed loop water systems?

Detecting Hidden Leaks in Mechanical Systems

Detecting Hidden Leaks in Mechanical Systems Page 27

• Look for WaterSense and ENERGY STAR labels on fixtures and machines

• Install low-consumption (LC) or high efficiency toilets (HET)

• Install low-flow showerheads

• Choose front-load washers, which are more efficient

Fixtures and Appliances

Fixtures and Appliances Page 28

Typical Water Use in Commercial Buildings

Water use in different types of buildings varies dramatically

Water Consumption Norms: Commercial

Water Consumption Norms Page 28

• Replace conventional plantings with native, climate-adapted plants

• Manage irrigation schedules

• Use a drip irrigation system instead of a hose

• Invest in a sensor and timer that will activate the irrigation system only when needed

• Maintain your irrigation system to prevent leaks

• Irrigate with greywater or harvested rainwater instead of potable water

Reducing Water Use for Irrigation

Reducing Water Use for Irrigation Page 29

BRAINSTORM:

What are ways you are already reducing your water consumption?

What are ways to get management to spend money on water efficiency upgrades?

TEST YOURSELF:1. How is using a single-dial water meter different

from using a compound water meter?

2. What are two ways to check for water leaks in boilers?

3. Name two or three causes of water use spikes.

4. Describe three or four ways tenants can reduce water consumption.

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LET'S TAKE A BREAK!

Green Professional Building Skills Training

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Operations and Maintenance Essentials