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• This version of the presentation includes the theory portion of the session. Examples from Prism projects and clients are not included. For further information or details, please contact the presentor

SPONSOR: Heather Scholefield, Program Manager Commercial Marketing Reid Arkinstall , Marketing Specialist, Conservation and Energy Management

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Prism Engineering provides consulting services to address technical, behavioral and organizational aspects of Energy Management We design and implement cost effective approaches to address comfort, efficiency and reliability.

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• Schedules

• Setpoints

• Sequences

• O&M Practices

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Item Measure 1 Reduce Equipment Runtime

2 Optimize Economizer Operation

3 Eliminate Simultaneous Heating and Cooling

4 Optimize Supply Air Temperature

5 Optimize Zone Temperature Setpoints

6 Eliminate Unnecessary Lighting Hours

7 Optimize Ventilation Rates

8 Volume Control for Pumps and Fans

9 Add / Improve Chilled Water Temperature Reset

10 Eliminate Passing (leaky) Valves

Schedules

Sequences

Sequences

Sequences

Sequences

Setpoints

Setpoints

Setpoints

O&M

Schedules

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• Real examples from Prism Engineering energy audits, COp, Energy Manager roles and DDC optimization contracts

• Practical scenarios that can be applied to your buildings

• Sectors include MURBs, education, health care, municipalities, offices, retail/hospitality

• 50 screen shots from a wide variety of DDC system providers

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• Weekly Schedules

• Occupancy Feedback

• Exception Schedules

–Holidays

–After Hours Use

–Special Events (ie Voting Day)

• Optimal Start

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• Optimal start/stop setback / setup

– In heating mode: Bring systems on earlier on colder days when needed and later on warmer days

–Can amount to 3% of heating energy savings

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1. Align system schedule with occupancy

2. Ensure target temperature setpoint aligns with room temperature setpoint

3. Set reasonable maximum start limits

School

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• Maintain Energy Efficient Space Temperatures with a deadband

– Heat to 21C

– Cool to 24C

– Revise based on particular space needs

• Maintain Humidity and Pressure

– Meet requirements of space

Overheating or overcooling of spaces results in higher ventilation loads and thermal losses

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• Reset Temperatures (Water and Air)

• Outside and mixed air damper controls

• Simultaneous Heating and Cooling

• Shut down pumps

• Static Pressure Reset

• Zone Isolation

• Optimize VAV Operation

• Demand Control Ventilation

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• Full recirculation mode for warm up / set back period

– Reduce outside air that needs to be heated when there are no occupants

• Automatic supply temperature reset on demand

– Varying reset with season & occupancy

– Avoids unnecessary reheating during spring & fall

– Typical savings of 3% of heating energy required

• Reset of heating water temperature on OAT

– Applies to heating water systems (boilers) and radiation systems

– Reduces overheating

– Can reduce boiler standby if boiler water temperature is also reduced

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Proper operation of mixing dampers

–Bring in only as much outside air as is needed

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• Air handling systems are designed to provide adequate fresh air to meet code and guidelines (ASHRAE 62.1)

• Minimum damper setting should be sufficient to provide these ventilation requirements

• Install CO2 transmitters and provide feedback to modulate outside air damper

• Under periods of low occupancy, reduce outside air rate

• Works best for spaces with variable occupancy (gymnasiums, auditoriums, etc.)

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• Warm weather shut down:

– Typical standby losses: 5-6% of rated input if boiler is pumped continuously

– 1MBH boiler on hot standby: 60,000 BTU/h of losses

• Multiple Boiler sequencing

• Run boiler pumps only when boiler is firing

• Optimize Condensing

• Ensure heat recovery is recovering heat!

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• Reduce compressor cycling

• Optimize multiple chiller sequence

• Optimize the condenser loop

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• Calibrate / commission sensors

– Temperature

– Pressure

– CO2

– Flow

• Identify / repair broken dampers

• Identify / repair passing valves

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• A management system is needed to establish: Who does what and when?

• Need to track activities. Log books?

• Engage DDC operators, maintenance staff, planning (work orders?) and the relationship between these parties

• Caution: do not make any changes without considering impact on codes

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• Graph shows natural gas savings but there are lower runtime hours for the 50 HP fan so electrical savings as well.

• DDC changes made:

– Monday start up time was 02:30h which we moved to 06:30h.

– T-F weekday start up time for the building was at 04:30h on weekdays - we moved it 06:30h.

– There was a schedule to heat the building for the occasional weekend. We changed that schedule from 8-16:00h Sat and Sunday to 9-12:00h

1000 GJ savings in last 12 months

Municipal Hall

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• two of our most energy intensive buildings at UNBC

• combination of scheduling changes to more closely match occupancy times (lighting, air exchange, temperature), and staged pump control.

• As lab buildings, they have significantly greater energy consumption needs.

• DDC is the place to start for scheduling automated building controls.

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• Schedules – Align Equipment Operating Schedules with Occupancy

– Use Holiday and exception scheduling effectively

• Setpoints – Ensure Temperature Setback/Setup during Unoccupied periods

– Put in place optimal temperature and pressure setpoints

– Ensure that all outside ambient lock outs have correct set points

• Sequences – Use air and water reset schedules

– Ensure that all heating and cooling pumps are shut down when not needed

– Reduce or eliminate simultaneous heating and cooling

– Temperature and ventilation reset on demand

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• O&M practices – Ensure that outside air sensors are calibrated and reading correctly. An

outside air sensor is used in various programs for scheduling.

– Ensure proper operation of dampers and valves

– Ensure proper outside air quantities

• Process and Procedures – Need management process for optimizing DDC

– WHO needs to do WHAT and WHEN

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Robert Greenwald, P.Eng., MBA, President

@Rob_Prism

Tel: 604-205-5500

robert@prismengineering.com

www.prismengineering.com

320 - 3605 Gilmore Way, Burnaby, BC V5G 4X5