Schneider-HVAC and Energy Efficiency

HVAC and Energy EfficiencySpeaker : Kelvin Ong

Energy efficiency with Power & Automation

2Schneider Electric Inspiration 2008Energy Efficiency with Power and Automation

What will I explain during this seminar?

Energy Efficiency

HVAC Equipment Overview

Our Solution


Lifecycle solutions for Energy Efficiency

Passive Energy Efficiency

Energy Audit& Measurebuilding, industrial process

Fix the basicsLow consumption devices,Insulation materialPower factor correction

Optimize through Automation and regulationHVAC control, lighting control,variable speed drives

Monitor, maintain, improveMeters installation Monitoring servicesEE analysis software

ControlImprove

ActiveEnergy Efficiency


Control and monitoring technologies will sustain the savings

Ener

gy

Con

sum

ptio

n

100%

70%

Effi

cien

t dev

ices

and

inst

alla

tion

Opt

imiz

ed u

sage

via

auto

mat

ion

Monitoring & Maintenance

Up to 12% per year is lost without regulation and control systems

Time


Overview of a building HVAC system

Water Stage Components Chillers Boiler Cooling Tower Pumps

Air Stage Components Air Handling Unit (AHU) Fan Coil Unit (FCU)

Heating-Ventilation-Air Conditioned System


HVAC typical equipments setup


Chiller systems

Different cooling system

Air cooled Chiller :

Condenser fan Compressor Chiller pump Air handling unit

Water cooled Chiller :

Tower fan Compressor Chiller pump Condenser pump Air handling unit

Rooftop units:

Condenser fan Air handling fan Compressor

Self-contained units :

Tower fan Compressor Condenser pump Air handling fan

Packaged systems


The ChillersA key component of most air-

conditioning systems

One of the major energy consumer

Functions : generate cooling and removing heat from a building

Refrigerant based chiller : the most common type (fridge)

Centrifugal Water cooled

Air cooled


Refrigeration: the states of matter

Heat must be added to a substance to make it change state :

from solid to liquid

and

from liquid to gas

Heat must be removed from a substance to make it change state :

from gas to liquid

and

from liquid to solid

liquidsolid gas

gasliquid

solid


What is inside a chiller?Evaporator

Heat exchanger from water to refrigerant and collect more heat (heat absorbed)

Compressor Vapour compression pump, compress

the refrigerant gas (temperature rise)

Condenser Heat exchanger remove heat from the

hot compressed gas and condense it to liquid (heat released)

Expansion Valve Restricts the flow, forcing the liquid to

go through a small hole which cause a pressure drop (temperature drop)


Air-Cooled Chiller

Compressor

Expansion deviceChilled pump

Condenser Fan

Evaporator

Cooling coil

Air 6C

13C

3C

10C 50C

43C

Chilled Water Loop Refrigerant


Cooling tower fan

Compressor

Expansion device

Condenser pumpChilled pump

CondenserEvaporator

Cooling coil

Air 6C

13C

3C

10C 50C

43C

38C

29C

Chiller

Water-Cooled Chiller

Chilled Water Loop

Heat Rejection Loop

Refrigerant


Chilled Water Loop Cooling Coil :

The cold liquid flowing through the tubes can be water or liquid refrigerant. The heat is exchanged from the air and transferred to the water flowing through the coil.

Evaporator : It s a heat exchanger and basically cools

the warmer water from the outflow side of the cooling coil. The heat is exchanged from the water to the refrigerant inside the evaporator.

Control valve : can be used to vary the quantity of water

flowing through the cooling coil.

Pump : moves water around the loop

Cooling coil

Evaporator

Chilled pump

Air


Heat Rejection Loop

Condenser : transfers heat from the hot refrigerant

to air, water or some other fluid.

Cooling tower : allows heat transfer from the water to

the air.

Pump : needed to move the water in this loop.

Control valve : can be used to vary the quantity of

water flowing to the cooling tower.

Cooling tower fan

Condenser pump

Condenser


Cooling Tower FanCooling tower is an important part of

many HVAC system

The cooling tower fan removes heat from water

The cooling tower fan speed is controlled to maintain the optimal condenser water temperature

The fans are the number-one user of power in a cooling tower, and that's the first place to look for energy savings

There is an advantage using drives because fan power varies as the cube of the air rate and thermal performance varies directly as the air rate


Power ControlCircuits

Pressure/ElectricalTransducer

Set PointController

TemperatureTransmitter

AC Line

Speed Reference

Auto

ManualOptionalBypassCircuit

27C-29CElectrical

CONDENSER WATER RETURN CONDENSER WATERSUPPLY

COOLING TOWER COOLING TOWER

Optional Cooling Towers

Typical Cooling Tower System


Air Handling Unit (AHU)

The AHU is the indoor unit, which includes a coil and an air blower

Its job is to circulate conditioned air throughout the building

In an AHU, the fan is the largest energy consumer


Constant Air Volume - CAV

Room Temperature Control Temperature is monitored at the Return Air (RA) Chilled Water Supply (CHWS) flow through the cooling coil is regulated based on RA

temperature The faster the flow of the CHWS, the faster the cooling rate of the blow air

RETURN AIR

OUTSIDE AIR

COOLING COIL(AHU)

Thermostat

Set temperature: 23C

Return temperature: 25C

Cold air temperature: 22C


Chain Reaction of CAV System

Return Air temperature -> Chilled Water Supply Valve

Chilled Water Supply Valve -> Chilled Water Pipe Pressure

Chilled Water Pipe Pressure -> Chilled Water Pump SpeedChilled Water Pump Speed


Variable Air Volume - VAV

Room Temperature Control Damper opening of each VAV box is regulated

To maintain the temperature at the set pointPressure Control

Damper opening after the AHU is regulated to maintain duct pressureCold Air Supply Temperature

Chilled Water Supply flow rate through the cooling coil of the AHU is regulated based on Return Air (RA) temperature

RETURN AIR

OUTSIDE AIR

COOLING COIL(AHU)

StaticPressure

Thermostat22C

Thermostat23C

Thermostat24C

Thermostat

Set temperature: 23C

Return temperature: 25C

Cold air temperature: 22C


Chain Reaction of VAV System

Temperature of each room -> Damper opening/closing

Damper opening/closing -> Pressure of the main duct

Pressure of the main duct -> AHU Fan SpeedAHU Fan Speed

Return Air temperature -> Chilled Water Supply Valve

Chilled Water Supply Valve -> Chilled Water Pipe Pressure

Chilled Water Pipe Pressure -> Chilled Water Pump SpeedChilled Water Pump Speed


Typical AHU Control System

Pressure Regulation of the AHU using VSD

Power ControlCircuits

Pressure/ElectricalTransducer

Set PointController

PressureTransmitter

AC MotorFan

AC Line

Speed Reference

Auto

ManualOptionalBypassCircuit

3 to 15 PSIElectrical

AC MotorOptional

FanOptional


Why variable torque load can saves energy?

Torque varies as the square of speed (centrifugal load)T = k w

Power = Torque x Speed

Power = k W x W = k W

Hence, power varies as the cubic of speed!

Speed

Torque

Centrifugal Load:FanCentrifugal Pump


Fan Flow Rate Control Using Damper

Placing damper at the DOWNSTREAM to control the flow rate by changing circuits characteristic

LESS efficient

Placing damper at the UPSTREAM to control the flow rate by changing the fans characteristic

MORE efficient


Fan Flow Rate Control Using VSD

Fans characteristic at two DIFFERENT SPEEDs

Shifting of fan curve downwards

Shifting of the fans characteristic at different operating speeds and the resulting flow rate

Energy consumption reduced!

Please visit our booth for LIVE

demonstration!


Where can energy optimisation can be implemented?

Cooling TowerControl cooling tower fan speed by monitoring the returned condenser water

temperature

AHUControl fan speed to maintain pressure of the main duct while the load

changes

Chilled Water PumpControl pump speed to maintain pressure of the piping while the load

changes


Where are the drives potentially can be installed?

Chiller

Fan

Cooling tower

Chilled Water Pump

PumpPump

Condenser Pump

Supp

lyai

r Fa n

Sup p

lyai

r Fa n


Our solution to HVAC

Lifecycle approach EE SolutionS54 IP54 Enclosed Drive with Bypass StarterATV21/61 HVAC Drive


Passive Energy Efficiency

Energy Audit& Measure

Fix the basicsOptimize through Automation and regulation

Monitor, maintain, improve

ControlImprove

ActiveEnergy Efficiency

Measure = Conduct site measurement and study

Fix the Basics = Power Quality, Harmonic mitigation solution, VSD

Optimise = HVAC Control (TAC), Lighting Control (Clipsal)

Monitor and Improve = SCADA (Vijeo Citect) and BMS (TAC)

Lifecycle solution approach


S-54 IP54 Enclosed Drive Offer

Range: 0.75kW to 75kW IP-54 rated enclosure Thermal studies conductedBy-pass starter built-in Local standard adaptation

Target HVAC Market:Commercial buildingsHotelsGovernment facilitiesSchools and Universities

Please visit our booth for this Plug nPlug n PlayPlay

Solution


Design Consideration

Type 1 Coordination component selectionCircuit breaker + contactor + thermal overload Type tested components to ensure maximum safety to personnel

IP54 rating and thermal study of the panelPSB tested

Bypass Starter for Emergency Use < 15kW: DOL Bypass >= 15kW: Soft-starter bypass

VSD with C-Less TechnologyCurrent Harmonic Level, THDi < 35%


Variable speed drives

Variable torque offer for 3-phase asynchronous motors:From 0,75 to 30 kW3-phase 200/240 V and 3-phase 380/480 VUL Type 1 / IP20 and IP54Integrated EMC class A or B filters

Altivar 21A breath of fresh air for yourHVAC applications!

Variable speed drives

Variable torque offer for 3-phase asynchronous motors:From 37 to 220 kW3-phase 200/240 V 380/480 VUL Type 1 / IP20 and UL Type 12 / IP54Integrated EMC class A or B filters

Altivar 61At the heart of yourHVAC applications!


Some example on energy savings...

Energy Saving Calculation Tools

Used in Fan & Pump application


In summary...

EE is not short term effort, but a long term effort.

Active Energy Efficiency - Continuous control and monitoring program shall be in placed in order to sustain the savings

Potential of 30% reduction in energy consumption in existing building, through today technologies, control and automation

Schneider is able to provide comprehensive EE solution to our customer life cycle EE solution approach!


Questions ?

Helping you make the most of your energy!

Speaker : Kelvin OngEmail : [email protected] number : 64855197

Schneider Electric Inspiration 2008Energy Efficiency with Power and Automation

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Schneider-HVAC and Energy Efficiency