Arenas Workshop

Fredericton, March 22nd, 2011

Energy Efficiency in Arenas and

Curling Rinks

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Our Mission

About Efficiency NB

Crown Corporation established in November 2005. (White Paper can be found at: http://www.gnb.ca/0085/toc-e.asp)

Located in Saint John.

Efficiency NB offers sound advice and practical

solutions to help New Brunswickers

use energy more efficiently;

make better energy choices;

manage energy expenses; and

lessen the impact of energy use on the environment.

Defining the Sectors

RESIDENTIAL COMMERCIAL LARGE INDUSTRIAL

Target: Base Building Energy

Efficiency

Target: Process Improvement,

Co-Gen, etc.

EXISTING ENERGY SMART

SMALL & MEDIUM

MANUFACTURERS

and LIGHT INDUSTRIAL

(BNB, ACOA, NRCan, others)

NEW HOMESSMART START &

CORE PERFORMANCE

MURBs

Marketing and Public Outreach

Energy Management 101

www.nwcommunityenergy.org/biogeo/efficiency

Commercial

Energy Efficiency Programs

Energy Smart for Retrofits

Grant of up to $3,000 for an energy audit Grant of up to $50,000 toward the energy retrofitting project cost

Start Smart for New Construction

Modelling Path

Grant of up to $60,000

Start Smart for New Construction

Prescriptive Path

Grant of up to $60,000

Energy SmartFinancial Incentives Breakdown

* *

Energy Savings

24.3% 22.8% 10.3%Average decrease in

energy costs:

Start Smart Program Options

Minimum Performance: 30% better than the Model National Energy Code of Canada for Buildings (MNECB 1997). ENB currently accepts models completed with EE4 or eQUEST software.

Modelling Path Requirement

Minimum Performance: 30% better than Model National Energy Code of Canada for Buildings (MNECB 1997) by complying with the Core Performance Guide Efficiency NB Edition

Prescriptive Path

Requirement

Incentive is 2x

estimated annual

energy savings up

to $60,000 max.

Incentive is

$1.50/sq/ft up to

$60,000 max.

Agenda for the day

Objectives The fundamentals: Energy context and energy efficiency Arenas & Energy Typical Arena Profile Energy Use in Arenas and Utility Data (M&T) Refrigeration Loads Energy Efficiency Measures

Lunch Break

Benefit / cost analysis: making the case for energy efficiency Available Tools for Arenas and Curling Rinks Energy Management Planning Measurement and Verification (M&V)

Energy Efficiency in Arenas

and Curling Rinks Workshop

Objectives

Objectives

Promote sustained energy efficiency improvements in New Brunswick Arenas and

Curling Rinks Stock

Provide information for adequately evaluating the energy use in arenas

Enable to qualify the savings estimates obtained for energy efficiency measures

Assist in successfully implementing energy efficiency measures

Provide methods for ensuring savings persistence

Objectives

Present energy efficiency as a process, not an isolated

action: the Energy

Management Plan Requires to know where

energy goes

Need to know the major factors influencing energy use

Identify the efficiency measures and tools available

The fundamentals:

energy context and energy efficiency



Why energy efficiency?

Customers want energy services (light, heat, automotion), not energy (kWh, GJ)

Energy services can be delivered with more or less energy (ergo more or less productively).

EE is not a virtue; it is a process by which we focus on the service required, and how to deliver it the most

efficiently

An energy efficiency project can thus be compared with a regular project on their merits.

Energy context and efficiency

Benefits of energy efficiency

Least cost

B/C tests to confirm and select options

Least risk

No fuel price volatility CO2 market what will it mean

Least environmental impacts

Climate change is energy Greenhouse gas emissions rising due to growing energy demand


Reduced risks Energy consumption primarily based

on two ressources: Electricity

Approx. 45% of NB energy mix Fuel Oil

Approx. 35% of NB energy mix

Both energy sources carry a significant price uncertaintyin the near future


Electricity generation in NB 45% of energy consumption

Strong presence of carbon-based fuelsSince 2008, new renewables in the electricity mix

mix


Carbon-based electricity Greenhouse gas emissions constraints will increase in

the near future

NB has committed to a Renewable Portfolio Standard 10% Eco-logo certified energy by 2016

Low-impact, low GHG electricity Utilities will lower their carbon intensity in response to the

market pressure.

Carbon constraints will potentially lead to higher RPS target upward pressure on $/kWh

Electricity generation NB Power (2009): 0.578 kg CO2e / kWh Canadian Electricity Industry (2009): 0.29 kg CO2e / kWh


Fuel oil 35% of energy consumptionPrice volatility -

65

75

85

95

105

115

125

135

145

July

, 2006

January

, 2007

July

, 2007

January

, 2008

July

, 2008

January

, 2009

July

, 2009

January

, 2010

July

, 2010

January

, 2011

NB Furnace Oil price

85

90

95

100

105

110

115

120

March-10 to March-11


1850 1875 1900 1925 1950 1975 2000

Emissions x 20

Energy x 30

1860=1

Efficiency = environment

Climate change IS energy Greenhouse gas (GHG) emissions rising due to

growing energy demand

Two options to reduce GHG:

Greener supply Lower demand



Homo sapiens appearIndustrial

era begins

Last Ice Age

(1/3 ice cover)

2005: 379.1 ppm



Arenas & Energy

Market Overview

In Canada2 300 Arenas1 300 Curling Rinks

A typical arenaUses 1 500 000 kWh eq./yrHas $ 100 000/yr energy cost

Unit Cost and UseApproximately 40 ekWh/ft2 or 1.7 GJ/m2

Approximately $2.80/ft2 or $30/m2

Market Overview

In New Brunswick90 Arenas38 Curling Rinks

A typical arenaUses 930 000 kWh eq./yrHas $ 95 000/yr energy cost

Unit Cost and UseApproximately 26 ekWh/ft2 or 1.0 GJ/m2

Range of 0.3 to 2.2 GJ/m2

Approximately $2.70/ft2 or $29/m2

Market Overview

A typical Curling RinkHas 3 curling sheetsUses 180 000 kWh eq./yrHas $18 000/yr energy cost

Unit Cost and Use approximately 20 ekWh/ft2 or 0.8 GJ/m2

approximately $2.00/ft2 or $22/m2

Market Overview

Importance of market segmentTotal of General Service clients in the Province

Estimated at 2 600

Total Arenas and Curling Rinks Estimated at 128 customers

Less than 0.5% of all General Service customers

Electrical Energy Use Total for General service customers: 2 600 GWhTotal for Arenas and Curling Rinks: 80 GWhRepresents over 3% of total General Service670% more than their representation in terms of

number of customers

Market Overview

Market Overview

Global Efficiency PotentialA study done by CanmetENERGY suggest a 41%

reduction potential for the existing arenas stock

New efficient design can target a 50% reduction using an integrated approach: Refrigeration and HVAC are inter-linked in the

design

For New Brunswick:Over 30 GWh of recurrent savings For the average arena:

300 000 ekWh reduction $23 000/year savings

Market Overview

Global Efficiency PotentialTop measures identified (no specific order)

1. Low emissivity ceiling

2. Brine pump optimization

3. Discharge pressure control

4. Heat recovery for resurfacing hot water

5. Heat recovery for domestic hot water

6. Ice temperature control

7. HVAC control (scheduling)

8. Lighting retrofit

9. Heat recovery for space heating

10. Humidity control



Typical Arena Profile


Typical ArenaSingle ice sheet: 16 000 ft2

Total building size: 30 000 to 35 000 ft2

Operation: mi-September to mid-April Installed refrigeration capacity: 80 Tons Refrigerant: AmmoniaEvaporative condensersSingle running brine pump55 Floods/week @ 65 oCRink lighting: 18 kW, Metal HalideCeiling emissivity: 0.85Constant condensing pressure


Typical ArenaHVACMakeup air for dressing rooms, no HRVExhaust fans for the bleacher/rink sectionBaseboard and force flow heaters (some with

boiler/hydronic heating)

Bleacher: limited heating 5 oC average interior temperature (rink/bleacher zone)

No heat recoveryDehumidifiers (direct expansion)Mostly manual controls or local controllers (ice

plant), no BAS (Building Automation System)


Typical Arena Refrigeration Layout No integration

with heating or

hot water



Energy Use in Arenas & Utility Data

Taking it from the Top

Steps in controlling energy use and cost Utility Data and Rates You cant control what

you dont measure Benchmarking compare your building Find When Energy is Used Find Where Energy is Used Eliminate Waste Maximize Efficiency Optimize Energy Supply

Energy Rates

Commercial Rate Structure - Electricity

Example General Service

First 20 kilowatts of demand No charge

Additional kilowatts of demand $9.66/kW

First 5000 kilowatt hours 12.07/kWh

Balance kilowatt-hours8.56/kWh

10 100 W bulbs running for 1 hour in a month in an arena would represent an energy

cost of $0.0856 and a demand cost of $9.66, if

they were on during Peak time.

Energy Rates

Commercial Rate Structure Gas, OilExample General Service

Delivery$12.42 /GJ

Commodity$7.50/GJ - No multi-tier structure

Oil rate per L

Estimating energy use and cost Having an inventory of your electrical and fuel-fired

equipment helps in getting insight into your energy

usage and cost.

Energy Rates

Arena Electrical Equipment (partial)

hp kW BTU/h h kWh MMBTU

Compressors 160 400 35,808

Brine pump 20 744 8,325

Rink Lights 18 225 4,050

Outdoor Lights 4 370 1,480

Condenser Fans 10 300 1,679

Cooking Appliances 30 120 1,800

Infra-red heaters 450,000 180 81

Total 190 52 450,000 53,142 81

1 hp = 0.746 kW

Assume 75% motor loading, 50% kitchen appliance cycling

Cost Estimation

hp kW

kW On

Peak

$

Demand kWh

$

Energy

$

Gas

Compressors 160 90 $ 672 35,808 $ 3,669

Brine pump 20 11 $ 108 8,325 $ 713

Rink Lights 18 18 $ 174 4,050 $ 347

Outdoor Lights 4 0 $ - 1,480 $ 127

Condenser Fans 10 6 $ 54 1,679 $ 144

Cooking Appliances 30 15 $ 145 1,800 $ 154

Infra-red heaters 0 $ - 0 $ - $ 1,702

Total 190 52 139 $ 1,152 53,142 $ 5,152 $ 1,702

Estimating energy use and cost Cost estimate can be difficult due to the demand and

multiple tier structure for electricity

Energy Rates

Assume that base demand and consumption attributed to the compressors

1.05506 GJ = 1 MMBTU

Energy Use Index

Comparing Apples to ApplesConvert all energy use into the same set of units, such as:

All in GJAll in equivalent kWh (ekWh)

Gas 1 GJ : 277.78 ekWh

1 GJ : 26.86 m3

1 m3 : 10.342 ekWh

Oil 1 GJ : 277.78 ekWh

1 GJ : 25.82 L

1 L : 10.76 ekWh

Electricty 1 GJ : 277.78 ekWh

Propane 1 GJ : 277.78 ekWh

1 GJ : 39.08 L

1 L : 7.11 ekWh

Energy Use Index

The Energy Use Index (EUI) allows comparing (benchmarking) your facility

Convert all utility data into GJ or ekWhObtain Facilitys total conditioned area: for Arenas

and Curling rinks, includes the ice shed.

EUI = Sum of all energy consumption/Area

Example: 25 000 ft2 arena, 650 000 kWh and 15 000 m3 of gas EUI = 32.2 ekWh/ft2

Benchmarking

The Energy Use Index (EUI) allows comparing (benchmarking) your facility Compare internally with historical data Compare externally with regional, provincial or national

data (when available)

Benchmarking

Benchmarking Pitfalls Benchmarking data is often limited Benchmark database includes Facilities with very

different profiles, such as: All-year round ice Multiple ice Facilities Large and very small Facilities Heated and Unheated Facilities, etc.

Floor areas used in Benchmarking is not always consistent

Benchmarking against historical data is better or against a more local and better defined dataset

Energy Fingerprint of the Facility

Provides better clues to energy usage than the single EUI indicator

Can provide some End-Use breakdown information

Using monthly data is a necessity in a good energy management plan

Raw utility data often needs to be processed Variable reading periods

Estimated readings (mostly for gas)

Varying weather conditions

Monthly Utility Data

Variable reading periods


Read Date Days Demand Total Consumption Daily Average17Jan2006 33 188 81,760 2,47815Feb2006 28 183 76,640 2,73716Mar2006 28 99 40,640 1,45113Apr2006 27 211 81,280 3,010

16May2006 32 65 30,720 96015Jun2006 29 61 28,000 96617Jul2006 31 61 29,920 965

01Aug2006 13 185 41,026 3,15601Sep2006 30 185 87,913 2,93017Oct2006 46 185 140,661 3,05816Nov2006 29 181 82,400 2,84114Dec2006 27 189 61,920 2,29316Jan2007 32 107 79,520 2,48514Feb2007 28 107 68,000 2,42915Mar2007 28 188 78,720 2,81116Apr2007 31 178 60,800 1,961

16May2007 29 52 33,280 1,14815Jun2007 29 59 24,960 86117Jul2007 31 59 26,560 857

What happened?

Average daily data shows a more accurate picture


Moving annual totals: overall trend


Weather-sensitive component: consumption above the neutral month usage

Provides a estimate for heating due to weather (excludes heating caused by the ice sheet cooling effect)


Baselines

All electric arena

Oil heating and resurfacing water

Typically what is above the baseline = weather-dependant load

For combustible, the baseline represent loads such as service hot water (oil, gas) and cooking (gas)

Pitfalls for Arenas and Curling Rinks: For electrically heated building, the heating load will be

hidden by a reduction in refrigeration consumption during

the colder months and a higher one for the warmer months

The baseline will be difficult to define for these buildings


Energy monitoring and targeting is primarily a management technique that uses energy

information as a basis to eliminate waste, reduce

and control current level of energy use and

improve the existing operating procedures. It

builds on the principle you cant manage what you dont measure

It essentially combines the principles of energy use and statistics

Monitoring and Targeting

(M&T)

What do you need? Utility data for the last 12 to 36 months

Rink operating periods for that time span

Monthly Heating Degree-Days for that time span (can be obtained at no cost at http://www.climate.weatheroffice.gc.ca/climateData/canada_e.html

Basic knowledge of Excel

Time (the most difficult ingredient)


(M&T)

Note: Heating degree-days is an indicator of the heating

requirements for a building. It is derived from the difference

between the daily average exterior temperature and a

reference temperature (typically 18 degC)

HDD = summation over a period (ref temp - average temp)..

What to do Next Compile the Moving Annual Total as shown previously

Add a line for the Moving Annual Total for heating degree-days -> see if the energy trend follows the weather trend

Update monthly

You can stop here

but there is more


(M&T)

What to do Next Find a formula that predicts the baseline energy use and

compare the prevision to the actual utility data

Summing up the differences month after month provides you with the efficiency trend of the building this is called CUSUM analysis (CUMulative SUMmation)


(M&T)

kW

h/M

on

th

Energy Use in Arenas

Where is the energy going?Billing analysis provide mostly the WhenObtaining an End-Use breakdown is important in

a good EMP as it provides

Magnitude of each potential efficiency target in terms of energy and annual cost

Allow judging claims with regard to potential savings

An End-Use breakdown is a typical feature of an energy audit


Where is the energy going? Despite their many variations, arenas have

sufficiently similar characteristics to provide a fairly

typical breakdown (based on the typical arena presented earlier)


Where is the energy going?

End-Use kWh Cost

Refrigeration 389,453 $ 39,783

Pumps 60,000 $ 6,129

Hot Water- process 53,299 $ 5,445

Hot Water- sanitary 40,000 $ 4,086

Lights 140,000 $ 14,301

Fans 28,509 $ 2,912

Heating 129,067 $ 13,184

Miscellaneous 92,149 $ 9,413

Total 932,477 $ 95,253


For a partially heated rink with some mechanical ventilation, such as our typical arena, the heating

load is divided as follows



Refrigeration Loads

Refrigeration Loads

Refrigeration is by far the largest single End-UseMost opportunities will be linked to

refrigeration

Most complex mechanical system in an arena or curling rink

It is important to understand what makes up the load on the refrigeration

system

Refrigeration Loads

Typical load break down (based on the typical arena profile)

Refrigeration Loads

Typical peak load break down equipment sizing (based on the typical arena)

Refrigeration Loads

Summary of Heating and Refrigeration Loads in an Arena

Air infiltration

Roof Heat Loss

Air Temperature

and Humidity

Infrared

radiation

Lights

Skaters

Floodings

Exhaust & Fresh Air

Walls Heat Loss

Under slab heating

Slab Heat Loss

Source: retscreen.net

Refrigeration Loads

Typical load break down (based on the typical arena profile)

Load Component kWh of Load Cost of Load

Air temperature 112,898 $ 11,533

Humidity 80,696 $ 8,243

Ceiling radiation 57,795 $ 5,904

Ground and piping 28,140 $ 2,874

Resurfacing 52,263 $ 5,339

Lighting 16,816 $ 1,718

Pumps 28,743 $ 2,936

Skaters 12,102 $ 1,236

Total 389,453 $ 39,783



Energy Efficiency Measures


As indicated earlier, the energy efficiency potential for Arenas and curling rinks is

significant

It is important to know the most common measures

The measures are all articulated around the stated principles of: Eliminating Waste a combination of low cost

and capital cost measures Maximizing Efficiency typically capital cost

measures Optimizing Energy Supply in our energy

efficiency context, concerns mostly renewable energy


Refrigeration-related Measures1. Low emissivity ceiling

2. Brine Pump Control

Infrared sensor Two-speed pumps Variable speed pumps

3. Ice temperature control scheduling

4. Discharge pressure control

5. Bleacher temperature control

6. Dehumidification

7. Ice thickness control

8. Adequate water volume for resurfacing

9. Condenser Heat Recovery for underfloor heating

10. Condenser Heat Recovery for snow melting


HVAC-related Measures1. Time scheduling of fans and exhaust

2. Temperature set back

3. Condenser Heat Recovery for space heating

4. Exhaust air heat recovery

5. High efficiency boilers and heaters

6. Heat pumps Air source and ground source


Hot Water-related Measures1. Desuperheater for resurfacing water

2. Desuperheater for resurfacing sanitary water

3. High efficiency water heaters (other than electric)

4. Low flow shower heads


Lighting Measures1. T5 or T8 for Rink Lighting with multilevel control

2. T12 replacement with T8 lamps

3. Lower wattage T8 lamps

4. Occupancy sensors


New Construction1. Integrated Design combining Refrigeration, HVAC and

Hot Water

EEM - Refrigeration

Low emissivity (low-e) Ceiling Every object emits infrared radiation (IR) Up to 30% of the ice sheet refrigeration load can be due to IR

radiation

Common materials have emissivity of 0.8 and more Low-e ceiling can have emissivity ranging from 0.05

(aluminized films) to 0.25 (special paints)

Emissivity is a measure of the propensity of

an object to emit IR radiation. A value of 0

indicate that it will not emit any IR while a

value of 1 shows that it is a perfect emitter.

Savings are strongly dependant on interior temperatures (ceiling,

floors and walls)

EEM - Refrigeration

Low emissivity (low-e) Ceiling Typical cost $30 000 Typical saving 60 000 kWh Savings will also be reduced when there is a radiant floor.

EEM - Refrigeration

Brine Pump Control IR Sensor Brine pumps are typically 20 hp in arenas and 15 hp in curling

rinks. They typically run 24 hours a day.

Approximately 90% of the energy consumed by the pump motor is transformed into heat in the brine loop

This is like having a 10 to 15 kW heater in your brine loop An infrared temperature sensor system will allow cycling the

brine pump to maintain the proper ice temperature.

EEM - Refrigeration

Brine Pump Control IR Sensor Typical cost $5 000 with sophisticated model reaching $20 000 Savings 30% - 40% of pumping energy and refrigeration impact 28 000 kWh for our typical arena

Refrigeration impact: Since most of the

pumping energy turns into a refrigeration

load, savings from pumping measures will

also save compressor energy. This also

applies to any measure that reduces the

refrigeration load.

How to estimate these interactive savings:

1- Estimate the load reduction kWhr2- The additional savings will be equal to

the load reduction divided by the average

efficiency of the refrigeration plant, often

call the Coefficient of Performance (COP)

3- Get the total savings as

kWh total = kWhr + kWhr/COP

A COP of 2.0 to 2.5 for an average age

refrigeration plant is typical.

EEM - Refrigeration

Brine Pump Control Two-speed pump Brine pumps are sized to deliver enough flow to satisfy peak

refrigeration loads that occur only a few hours a year. A two-

speed pump, or a smaller secondary pump, can operate most

of the time at low speed for major savings.

An infrared temperature sensor system is required to control the operation of the pump.

Typical savings: 50% of pumping energy and refrigeration impact

45 000 kWh Typical Cost: 15 000 $

EEM - Refrigeration

Brine Pump Control Variable pump Further savings can be achieved by continuously adjusting

the flow to the refrigeration load. Using a variable speed drive

on the brine pump can allow further savings compared to a

two-speed pump.

An infrared and a brine return temperature sensor system are required to control the operation of the pump.

Typical savings: 60% of pumping energy and refrigeration impact

55 000 kWh Typical Cost: 22 000 $

EEM - Refrigeration

Ice Temperature Scheduling Savings of about 1.5% of the total energy use can be obtained

for each oC of reduction of ice temperature (yearly averaged

reduction)

Adjusting the temperature for the type of activity and operating schedule is the optimal procedure.

Time scheduling is more easily implemented

Typical recommended ice temperatures Hockey: -6C to -5C Figure skating: -4C to -3C Free skating: -3C to -2C No activity: -2C to -1C Curling: -4C to -5C

EEM - Refrigeration

Discharge Pressure Control In many refrigeration systems, compressor discharge (head)

pressure is kept at a fixed, high level to assure safe, reliable

operation over a range of outdoor temperatures.

Its far more efficient to allow head pressure to float with ambient wet-bulb temperature, down to a minimum

safe level for a given system

For every degree you reduce the

discharge temperature the

efficiency will increase by

approximately 1%

Source: Energy Center of Wisconsin

EEM - Refrigeration

Discharge Pressure Control The minimum setting is very dependant on the systems

characteristics and consulting a refrigeration expert with

experience with floating head pressure is needed.

Using a lower pressure setting will result in longer operating times for condenser fans and using variable speed drives

would further increase the savings.

Typical cost to implement :$5 000

Typical savings:50 000 kWh

EEM - Refrigeration

Bleacher Temperature Scheduling Decreasing the stands average temperature set point has a

double effect in arenas. It results in heating savings as well as

refrigeration savings (interactive effect)

Savings of 2%/oC to 4%/oC

of the total

facilitys energy use are available

Dehumidification Will lower the latent load (humidity) on the ice and provide

better ice conditions.

Savings result from the higher efficiency of the dehumidifiers

EEM - Refrigeration

Dehumidification Desiccant dehumidifiers offer the largest savings More efficient at low indoor temperature Requires a heat source to regenerate the wheel, optimal

scenario is a gas regeneration to limit peak demand

Typical cost $60 000 Typical savings 70 000 kWh

EEM - Refrigeration

EEM - Refrigeration

Ice thickness control Typical ice thickness ranges from 25 to 40 mm thick. In some ice rinks with uneven slab surfaces, thickness

approaches 75 mm

Keeping ice thickness to about 25 mm provides the optimal energy usage

EEM - Refrigeration

Adequate water volume for resurfacing This is a purely operational measure aiming at insuring that

the amount of water put in the resurfacer and used in

resurfacing is optimal.

Loading a extra 10% water volume in the resrufacer translates into an annual cost of $550

Too much water for floods builds up ice thickness and results in additional use for freezing the water and decreases

refrigeration efficiency from thicker ice.

A typical flood only adds 0.25 mm to the ice sheet.

EEM - Refrigeration

Condenser Heat Recovery for underfloorheating Extended use facility usually have underfloor heating to

prevent frost heaving.

The typical heating capacity required is 5 to 10 kW Since the temperature required for underfloor heating is low, it

is an ideal application for condensing heat reclaim.

Savings: 20 000 kWh Cost: $10 000

EEM - Refrigeration

Condenser Heat Recovery for snow melting Some arenas can dump the snow outside the building Other must have snow melting pits that uses hot water to melt

the snow

Using recovered heat is a perfect application given the low temperature

The snow pit can be used to subcool the refrigerant going back to the compressors, further increasing the savings

It is important to avoid warming up the water past its freezing point to limit the humidity load going back into the arena.

The total energy use for melting

a full year worth of resurfacing is

equal to 70 000 kWh

EEM - HVAC

Condenser Heat Recovery for space heating A typical arena, or curling rink, rejects much more energy

than is required to meet its entire heating and hot water load

The majority of the energy is available at a low temperature, of 38 oC or less

Spaces with a low set points, such as the bleachers, can use this low grade heat

Spaces with higher set points can also benefit from heat reclaim but may need to use heat pumps to boost the

temperature level of the heating air

Implementation of building-wide heat reclaim in an existing facility is an expensive and often complex measure

EEM - HVAC

Condenser Heat Recovery for space heating Heat reclaim can technically replace all of the bleacher

heating but in practice there are times when the available heat

rejection does not match the heating need

Typical savings (bleachers recovery):

75 000 kWh

Typical cost: $50 000 The measure will

limit the minimum

discharge pressure

- there is an optimal

setting

EEM - HVAC

Heat pumps Air source and ground source Heat pumps in arenas can be used in combination with heat

reclaim for areas that have higher set points

Without heat reclaim, a high efficiency air-source heat pump will save 40% of the heating cost

A ground-source heat pump system will typically save 65% of the heating cost

For arenas, heat recovery will usually be used first Savings from heat pumps will be based on the remaining

heating cost

Energy savings are often not additive and have a cumulative

impact on each other. For example, a measure that results in

20% heating savings combined with another that brings 15%

does not result in 35% savings but 32% savings (0.8 x 0.85 = 0.68

or 32% total saving).

EEM - HVAC

Exhaust air heat recovery This is a standard EEM for any type of building and consist of

installing a heat recovery exchanger in the buildings make up air unit. A typical cost for the exchanger is $5 to $8 per CFM

(cubic foot minute) of outdoor air flow. It will about 15 kWh/yr

for a system operating 12 h/day.

Time scheduling of fans and exhaust Turning off ventilation provides large savings. Using a

programmable thermostat or time clock is an inexpensive way

for implementing this measure. Using a Building Automation

System (BAS) will allow more complex scheduling and other

control optimization. A BAS will typically produce a 15%

energy reduction, excluding refrigeration and hot water.

EEM - HVAC

Temperature set backA 1oC = 3% of heating bill (spaces other than rink). The measure can be implemented using programmable

thermostats or a BAS

High efficiency boilers and heatersBoiler tune-ups provides typical gains of 2.5% of boiler consumption

High efficiency condensing boilers have efficiencies of 90%+

EEM Hot Water

Desuperheater for resurfacing water Approximately 25% of the heat rejected by the refrigeration

system is available at a higher temperature sufficient to heat

the water needed for resurfacing

This part of the rejected energy is called the superheat. A specific heat exchanger, the desuperheater can be used to preheat the water needed for resurfacing

An additional storage tank is typically required since the energy available at the compressor and the demand for

resurfacing do not always match

Typical savings: 48 000 kWh Typical cost, with storage tank: $30 000

Desuperheater for resurfacing water -schematic

EEM Hot Water

EEM Hot Water

Desuperheater for service hot water This measure is similar to that for the resurfacing water The one significant difference is that a special heat exchanger

is required since the water is used for sanitary purposes.

Typically, a double-wall vented heat exchanger is needed.

Additional storage capacity is often added Typical savings: 36 000 kWh Typical cost, with storage tank: $25 000

EEM Hot Water

Other Hot Water Measures High efficiency water heaters (other than electric): An oil fired

hot water tank will have an Energy Factor of about 0.5 with the

best one at around 0.68. Gas heaters will have a base EF of

about 0.59 but can be as high as 0.70.

Low flow shower heads: All shower heads sold since the early 90s have a maximum flow of 3.5 usgpm. However, there are an

increasing number of models at 2.5 usgpm or less. Savings

will be less than the % of flow reduction since it has been

shown that lower flow translates into warmer and/or longer

showers. Expected savings would be reduced by a factor of

20%.

The Energy Factor is used to express the efficiency of

residential-type heaters. It represents the amount of heat

required to warm up a years worth of hot water divided by the amount of energy input into the heater to warm that water.

Energy output

Type

Luminous

efficacy

(lm/W) CRI

Typical Life

(h) Heat

Visible

light Infrared

Rink

Load

Incandescent 15 95+ 1 000 7% 9% 84% 93%

Halogen 24 95+ 2 000 8% 13% 79% 92%

Halogen - infrared 30 95+ 4 000 8% 13% 79% 92%

White LED 50 80+ 60 000 80% 20% 0% 20%

CFL 60 80 6 000 40% 25% 35% 60%

PL (U-tube) 70 80 10 000 40% 25% 35% 60%

T8 80 80 20 000 40% 25% 35% 60%

T5 90 80 16 000 40% 25% 35% 60%

Metal Halide 70 65 20 000 27% 23% 50% 73%

Metal Halide - pulse start 80 65 20 000 27% 23% 50% 73%

Sodium (HPS) 100 25 24 000 23% 30% 47% 77%

EEM - Lighting

Lighting retrofit is one of the most common EEM, if not the most common

It is important to know the efficiencies of the light sources For arenas, we must also consider the amount of heat sent to

the ice by the various types of lamps.

EEM - Lighting

Light source efficiency is not the only factor: the Colour Rendering Index (CRI), the lumen maintenance as well as the

fixture efficiency need to be considered.

Light levels need to be adjusted as per the requirements of the activities

Lumen depreciation: There is a

significant reduction in light output for

some type of lamps, called lumen

depreciation. For example, Metal Halide

lamps can loose up to 30% of their

output over their lifetime.

EEM - Lighting

T5 or T8 for Rink Lighting with multilevel control A measure that is becoming more and more common consist

in replacing the typical 400 W Metal Halide lamps with either

high output T5s or T8 fixtures

T5s and T8s have better CRI, lumen maintenance and equal or better luminous efficacy. Many fluorescent fixtures also have

better overall efficiency.

The fluorescents provide quicker start/restrike time the metal halide, easier multi-level control (6 lamps/fixture) and even

light distribution

EEM - Lighting

T5 or T8 for Rink Lighting with multilevel control Typical savings, including refrigeration impact: 35 000 kWh

using a bi-level switching scheme

Typical cost: $20 000

Before Total kW Hours per weekUsage -kWh/yr

Refrigeration impact -kWh/yr

Total -kWh/yr

40 - 400 W MH 18 100 54240 18018 72258After40 - 6T5HO 13 50 19440 5308 2474840 - 6T5HO 6 50 9720 2654 12374Savings (kWh) 35137Savings ($-Energy) $ 3,008 Savings ($-Demand) $ 346 Cost $ 20,000 Useful LifeFixture 20yrsLamp 16000hBallast 50000h

EEM - Lighting

For the other section of the arena, there are a large number of conventional

lighting measures, such as: T12 replacement with T8 lamps Lower wattage T8 lamps: using 28 W or 25 W T8 lamps to

replace 32 W lamps if the foot-candle requirement is still met

Occupancy sensors: for spaces with variable occupancy, such as conference room, or the cafeteria/snack bar section

of the arena

Interactive effect: More efficient lighting uses less energy but also

produces less heat. As a result, there is an increased load on your

heating system in the winter and a reduced load on your air

conditioning systems in the summer. This impact is commonly

called interactive effects or cross effects. For a typical heating dominated building, this impact result in a 50% reduction in net

savings (non air conditioned building)

EEM - Others

Many Facility specific EEM are possible, common ones include: Recommissioning (O&M) Renewable energy:

Solar air heating Solar water heating

Maintenance: Some significant savings are possible with good maintenance practice, especially in regard to

refrigeration (e.g. refrigerant levels, suction line filters, etc.)

Recommissioning (RCx) or Existing Building Commissioning (EB-

Cx): Consist in a systematic analysis of the operation and controls

of existing building equipment to insure that they meet the current

operating requirements in the most optimal manner. RCx projects

typically provide 10% to 30% savings with a payback of less than

two years. The smaller the building, the longer the typical payback.

EEM New Construction

Integrated Design combining Refrigeration, HVAC and Hot Water



Benefit cost analysis:

Making the case for energy efficiency

Energy efficiency

benefits

Tangible and intangible benefits

Improved reliability

Reduced utility expense

Improved employee productivity

Less pollution

Numerous organization barriers exist to energyefficiency projects

Need to be adressed in the business case

Barriers

Capital vs operation Energy is often considered as a fixed cost incurred to the

operation budget Higher capital investment in energy efficient technologies

lead to reduced operating costs Little incentives for engineers and managers to specify

higher cost equipments with long term potential energysavings

Capital investment opportunities Limited capital energy efficient project leading to reduced

expenses vying for same capital as other projects that may generate additional revenues

Barriers

Organizational commitment

in energy efficiency and energy management is critical to a successful energy management plan and to long term energysavings

Energy efficiency knowledge deficit

Regarding valuation techniques Regarding available technologies and benefits Regarding energy consumption of the facility

The first step

Energy audits are a requirement Know your baseline

Identify potential opportunities Allow to evaluate cost effectiveness of improvements

What is the value of my future savings compared to the cost of the project?

3 levels of audit standard guidelines can be found at: http://oee.nrcan.gc.ca/publications/fbi/m92-84-

1994/audit_contents.cfm?attr=20

Valuation techniques

Different techniques for different purposes

Simple / incremental payback

Annualized savings

Internal rate of return

Lifecycle cost analysis

Simple/incremental

payback

Simple / incremental payback

Amount of time required to return the value of the investment

Total first cost of improvements / first yr energy savings

Highly simplified technique

Best suited for general discussion than proper B/C analysis

Mostly used indicator but

Wrongly seen as a good indicator of cost-effectiveness

Simple/incremental

payback

Pros: easy, simple

Cons: does not evaluate time-value of money Does not value energy savings after the pay-back period,

even though they still occur

Does not answer the question: How much does it cost NOT to make the project?

Project parameters Financial parameters

Measure: Low-e ceiling Energy cost ($/kWh) 0.0856

Cost of project $ 30,000

Energy savings (kWh) 46089

Measure life (years) 20

B/C analysis

Yearly savings ($) $ 3,945

Simple paypack 7.60

Example: Low-e ceiling retrofit

Annualized savings

Annualized savings

Technique that takes into account the estimated usage life of the measure

Initial capital costs converted to annual equivalent over the expected life

Take into account time-value of money

Account for operation & maintenance costs

Net annualized savings =

annualized cost yearly savings

Annualized savings


Measure: Low-e ceiling Energy cost ($/kWh) $ 0.0856

Discount rate 6%




B/C analysis

Yearly savings $3,945.22

Annualized costs $2,615.54 Initial investment over project life - discounted

Annualized savings $1,329.68

Pros: Considers the complete life of the measure Take into account the time-value of capital investment

Cons: No sense of yield of investment




Often used for big capital projects

Defined as the Rate of return required for the present value of future savings to be equal to the current price of the

investment

Need to know the time series of future savings Does not consider the cost of capital


Measure: Low-e ceiling Energy cost ($/kWh) $ 0.0856

Discount rate 6%




B/C analysis

Yearly savings $ 3,945

Internal rate of return 6.28%


Lifecycle cost (LCC) analysis

Total cost of system over anticipated useful life

Initial capital costs Ops & Maintenance costs Financing costs Estimated usage life and residential value Expressed as the value of future cost and savings in todays

dollar as reflected by an appropriate discount rate Used to compare alternatives


Project parameters Financial parametersMeasure: Low-e ceiling Energy cost ($/kWh) $ 0.0856

Discount rate 6%

Cost of project $ 30,000 Interest rate 7%

Energy savings (kWh) 46089 Equity 50%Measure life (years) 20 Debt term (years) 15

B/C analysis

Yearly savings $ 4,323 Total lifecycle benefits $ 52,560 (Present value)

Project costs

Equity $ 15,000

Debt payments $ 1,647 Total lifecycle costs $30,995(Present value)Total lifecycle analysis $ 21,564


Summary - B/C analysis

Benefit cost analysis need to consider the completecosts of measures, as well as the total energy

savings of the project

Initial capital costs

Financing costs

O&M costs

Energy savings for the completeduration of the project

Time-value of money use appropriate discount rate

Summary - B/C analysis

Internal rate of return Is a measure of the investment efficiency Should not be used for mutually exclusive projects

Annualized life-cycle savings

Provide a measure of the value of the project


Provides the best evaluation of the current value of an energy efficiency project

Accounts for all costs and savings for the entire durationof the project

Discounts future money streams compared to currentdollars.

Additional benefits

Financial benefits are only one part of the equation

Additional benefits: Optimized operations Regulatory compliance Strategic maintenance planning Increased reliability and reduced downtime

The business case for energy efficiency should alsoclearly state the non-financial and indirect financial

benefits of the investment

And dont forget to include any grants or incentives during the B/C analysis



Available Tools

Available Tools

A number of free, publicly available tools on the marketRETScreen Arena & Supermarket ModeleQuest Hourly simulation2 versions, one with a simplified model and

one with a detailed modeling capability

CanmetENERGY CEFOR Excel spreadsheetEE Wizard for Arenas On-line tool, developed

for CBIP limited use for LEED, based on hourly

simulation

Available Tools

RETScreenExcel-based tool, easy to usePre-feasibility toolCosting and financial analysisGHG analysisLimitations due to its simplicityLimited Building envelope and HVAC

definition

No entries for Brine pumpsLimited Schedules

Available Tools

RETScreen Example

Available Tools

eQuestDetailed, hourly-based simulation tool Complex to useFeasibility/technical study toolCan be used for M&VLimitations due to its complexityRequires very detailed descriptionsRequires high user expertiseCalibration should always be done to within

10% of monthly utility data and less than 5%

of annual utility data

Must use weather data matching utility period

Available Tools

eQuest Example

Available Tools

EE WizardSimplified, hourly-based simulation tool Easy to usePre-feasability or feasibility tool depending on

user expertise

LimitationsWeb-based version has some pre-establish

defaults that cannot be changes

Limited HVAC systems availableWeb-based version does not allow using

local weather data matching utility data

period

Available Tools

EE Wizard Example (stand-alone)



Energy Management Plan

Energy Managment Plan

Recall Energy efficiency should not be an isolated

action: the Energy

Management Plan Requires to know where

energy goes

Need to know the major factors influencing energy use

Identify the efficiency measures and tools available

Need to formalize the

process and adapt it to

your specific Facility


Audits alone will often not achieve the full potential available in a facility. An audit, done

without an overall plan, is likely to have few of

its proposed measures implemented.

The audit should be a step taken within a broader Energy Management plan.

The plan must have the buy-in of all players involved, from the operating staff to the

facilitys manager and the owner. The plan must set specific goals and must

insure to provide the means to achieving these

goals.


Key Points in the Energy Management Plan Proper training for staff Coordination and prioritized by manager Financial backing from owner Availability of technical expertise, such as through audits Clear and achievable goals: avoid setting unreachable

goals based on hearsay Audits can help in setting goals Regular updates to the plan: there are always

emergencies that will be more pressing, the Champion

must take charge.

Clear responsibilities for everyone involved Communications: if goals cannot be met, need to re-

assess the goals, not looking for whos fault it is.


Key Points in the Energy Management Plan If one link fails, the entire chain breaks Operators must see the advantages of the Plan and have a

say

Managers must understand the rink operation and constraints

Owners must be aware of realistic goals


Typical Team Members Building operator To provide day-to-day experience,

opportunities, constraints

Representative from Facility Management Technical expertise, possible project management resource

Representative from the Financial Department insure the plan is done within the proper budgetary guidelines, and

other contractual and financial considerations

Representative for the Owner Overall plan orientation, priorities


Steps The EMP should be multi-year, spanning a minimum of

three years in its first instance.

The EMP should define the measures that will be taken for each year, the targeted savings, capital and training

requirements.

The EMP will need a sound technical base in establishing its targets and measures: the Energy Audits


The Energy Audit Integral part of the EMP Provides basis to establish quantifiable targets Provides list of measures to integrate into a multi-year

plan and capitalisation plan

Provide the baseline information on the Facility Provides the energy break down by End-Uses for the

Facility

Must cover all aspect of energy use Equipment Operational Maintenance Behavioural

Beware of sales pitch disguised in single measure audits


Type of Audits (ASHRAE)

Level 1 Walk Through AssessmentAssess a buildings energy cost and efficiency by

analyzing energy bills and conducting a brief survey of

the building. A Level 1 energy analysis will identify and

provide a savings and cost analysis of low-cost/no-cost

measures. It will also provide a listing of potential capital

improvements that merit further consideration, along with

an initial judgment of potential costs and savings.



Level 2 - Energy Survey and AnalysisIncludes a more detailed building survey and energy analysis. A breakdown of energy use within the building is

provided. Identifies and provides the savings and cost

analysis of all practical measures that meet the owners

constraints and economic criteria, along with a discussion

of any effect on operation and maintenance procedures. It

also provides a listing of potential capital-intensive

improvements that require more thorough data collections

and analysis, along with an initial judgment of potential

costs and savings. This level of analysis will be adequate for

most buildings and measures.



Level 3 Detailed Analysis of Capital Intensive ModificationsThis level of analysis focuses on potential capital-

intensive projects identified during Level II and involves

more detailed field data gathering and engineering

analysis. It provides detailed project cost and savings

information with a high level of confidence sufficient for

major capital investment decisions


Energy Audits The most commonly done type is the Level II. The major elements that should be found in a complete

Level II audits are:

1. Building Description: space functions and sizes,

applicable schedules, occupancy levels

2. Thermal envelope: General condition, type of

construction, estimated insulation levels, type and

size of fenestration, infiltration issues

3. HVAC: List of HVAC systems, identification of HVAC

type, main specifications of HVAC equipment,

operating schedule and control logic, estimated

outdoor and exhaust flows, description and

specifications of heating and cooling central

equipments and pumps


Energy Audits The major elements that should be found in a complete

Level II audits are:

4. Refrigeration: Description of system layout and

control logic. Equipment specifications

(compressors, pumps, condensers, heat recovery).

Document the major load components such as # of

resurfacing, low-e ceiling, bleacher set point

5. Domestic hot water: Type of heaters, capacity and

storage volume, set points and estimated usage.

6. Lighting: A room-by-room or Facility-wide lighting

count is often performed with identification of lamp

type, voltage and wattage

7. Maintenance: Type and frequency, general condition

of the various equipment covered in the audit.


Energy Audits The major elements that should be found in a complete Level

II audits are:

8. Plug Load and Equipment: Document other

miscellaneous loads, such as plug load and kitchen

equipment. A detailed count of small loads is not usually

done.

9. Past and proposed EEM: document EEMs that have

been installed recently (e.g. past 5 years) and those

already planned

10. An utility data analysis, preferably for the last 36

months. The analysis will often provide a weather

regression and trend analysis. Look at peak demand,

power factor and any anomaly

11. An energy break down by End Use, not based on typical

values, but specific to the facility.


Energy Audits The major elements that should be found in a complete Level

II audits are:

12. Benchmarking.

13. Proposed EEM: the list of EEM must cover the no-cost

and low-cost measure that pertain to operation,

maintenance, awareness as well as the capital cost

measures. Level II implementation costs are budgetary-

only. Savings estimate ($) must not be based on annual

average unit cost. Any practical constraints and other

requirements with regard to the EEM are also provided.

14. Incentives: Many Level II audit will provide information

(qualitative and/or quantitative) on applicable incentives

for the proposed measures.



Measurement and Verification

M & V

What is it? M&V is the process of using measurement to reliably

determine actual savings created within an individual

facility by an energy management, energy conservation or

energy efficiency project or program. As savings cannot

be directly measured, the savings can be determined by

comparing measured use before and after implementation

of a project, making appropriate adjustments for changes

in conditions. - Efficiency Valuation Organization (EVO)

Savings cannot be directly measured since savings represent the absence of something

M&V and M&T are closely related. M&V formalises the reporting of savings.

M & V

Why? Allow adequate feedback to EMP: funding, reinforcement,

recognition

Avoid Placebo Effect Trust but verify

M & V

How? There is an international standard that is widely accepted

for verifying savings: IPMVP

It outlines four different options that can be used to measure and verify savings

Savings = Base Year Usage Post Retrofit Usage +/- Adjustments

Options A and B (Isolation Retrofit Approach): Options A and B focus on the performance of specific ECMs such as items of equipment and installed retrofits that can be measured in

isolation from the rest of the building. Before and after

measurements are taken and compared to determine the

savings. A lighting retrofit is a good example for Option A.

Installation of variable speed drives is a good example for

Option B.

M & V

How?Savings = Base Year Usage Post Retrofit Usage +/- Adjustments

Options C and D (Whole Building Approach) These options are used when the nature of the ECM is not easily measured

in isolation from the rest of the building operations. This

could be typical of operational and control changes that

affect many areas of the building. The Option C approach

assesses savings at the whole-facility level by analyzing

utility bills before and after the implementation of the ECMs. Option D uses computer simulations and modeling of the

whole facility, usually when base year energy data is not

available or reliable. Installation of energy management

control systems (EMS) and training/awareness programs are

good examples for Option C.

Option C is the most common procedure adopted.

M & V

When? A proper M&V plan must be considered at the on-set of a

project, prior to its implementation

This is required since pre-implementation measurements may be needed

M&V can be done formally by an independent third-part, usually an Certified M&V Professional (CMVP) or it can be

done internally with a less formal approach as long as the

basis for the adjustments are done properly



Wrap-up

Arenas Workshop

Documents

Transcript of Arenas Workshop