Enhancing The Efficiency Of New And Existing Cooling Systems Dr Robert Lamb CEng FInstR Group Sales & Marketing Director Star Refrigeration Ltd

Why Should I Focus On Enhancing Efficiency?

Data taken from DECC – 2012 Energy and Emissions Projection Annex F

Total Cost Of Ownership EnergyAftercare

Start Measuring

Cooling Load What Factors Affect Efficiency? Operating Temperature Equipment Selection Equipment Operation Efficiency

Cooling Load What Factors Affect Efficiency? Efficiency

What Make Up The Cooling Load? Cooling Load Ambient Temperature Insulation Air/Moisture Ingress Product Load Electrical Load PeopleDefrosting

Reducing The Cooling Load Eliminate Poor Door Control Ambient Air = +32°C/70% RH Chamber= +2°C 1m 3 /s air ingress = 101kW Refrigeration CoP= 3 Refrigeration Power= 33.7kW Electrical Cost = 6p/kWhr

Reducing The Cooling Load Insulation Thickness Panel Thickness (mm)U Value (W/m 2 K)

Reducing The Cooling Load Insulation Thickness

Reducing The Cooling Load Free Cooling

Reducing The Cooling Load Free Cooling

Reducing The Cooling Load Switch To LED Lighting Original Install: 7 x 250W lights Continuous Operation 15,330 kWhr/yr LED Install: 7 x 48W lights Intelligent Operation 2,943 kWhr/yr 24/7 Operation 80% Saving 85% to 90% with intelligent control Improved visibility

Cooling Load What Factors Affect Efficiency? Operating Temperature Efficiency

Evaporating Temperature

Case Study - Room Temperature Change

Measured Saving At 5 UK DCs

Case Study - Room Temperature Change

Case Study – Data Centre Chillers

Condensing Temperature

Minimising Condensing Temperature Avoid Air RecirculationKeep Condensers Clean Efficiency Electronic Expansion Valves Time Temperature TEV EEV

Cooling Load What Factors Affect Efficiency? Operating Temperature Equipment Selection Efficiency

Main Electrical Consumers - Refrigeration PLANTROOM Electrical Consumption Compressor = 90% Condenser= 5% Evaporator(s)= 5%

Main Electrical Consumers - Chillers PLANTROOM Electrical Consumption Compressor = 75% Condenser=15% Pump(s) = 10% PUMP SECONDARY CIRCUIT

Evaporating Temperature

Compressor COP Vs Temperature - Chillers

Compressor Selection - Chillers Screw ChillerCentrifugal Chiller 1MW Chiller For Data Centre Cooling

Compressor Comparison - Chillers

Cooling Load What Factors Affect Efficiency? Operating Temperature Equipment Selection Equipment Operation Efficiency

Compressor VSD Case Study Process Cooling Case Study

Compressor VSD Case Study Process Cooling Case Study

Compressor VSD Case Study Process Cooling Case Study Pre-InstallInstall PeriodPost-Install

Condenser Fans Time Compressor head pressureFan control Without VSDs Temperature Without VSDs Off On 16.6kW On 33.3kW VSDs

Cooling System Condenser VSD efficiency OnOff Rejected heat OffOn Efficiency VSD Control

Cooling System Condenser VSD efficiency OnOff On Efficiency VSD Control

Cooling System Condenser VSD efficiency OnOff On Efficiency VSD Control

Condenser VSD Case Study Air Vol (%) Time (%/yr) Power (kW) hr/YrkWhr/yr ,62857, ,05117, ,57717, ,3147, ,1900 Total99,733 Example Calculation: Fan Motor 22 kW Days/Yr 365 Days Hr/Yr 8760 Hrs Inverter Loss 5 % Fixed Speed Operation

Condenser VSD Case Study Air Vol (%) Time (%/yr) Power* (kW) hr/YrkWhr/yr ,62860, ,05110, ,5774, , ,1900 Total75,978 Saving23,754 Example Calculation: Fan Motor 22 kW Days/Yr 365 Days Hr/Yr 8760 Hrs Inverter Loss 5 % Variable Speed Operation * Including Inverter Loss

Condenser VSD Case Study SiteTotal Fan Power (kW) Install Price SavingsAdditional Saving * Payback A37£34,828£5,094£1, B74£37,464£10,188£1, C60£33,494£8,260£1, D44£34,028£6,058£1, Total£139,814£75,978 Total Estate Estimated Savings 4 Sites 8 Condensers Calculations based on 8.5p/kWhr * Maintenance savings – motors, belts, better control

Condenser VSD Case Study Measured savings 13% higher than estimates

Reduce Load Summary Raise Operating Temperature Careful Equipment Selection Optimise Equipment Control Improving Efficiency

Star Refrigeration – From Humble Beginnings to the Natural Choice Pioneering Natural Refrigeration Technology since 1970 Star Refrigeration – From Humble Beginnings to the Natural Choice More than 300 staff in 11 locations across the UK and a number of agents in Europe and Asia Has expanded from an industrial refrigeration company to a multi- faceted engineering group The largest and most successful independent cooling and heating contractor in the UK Pioneering development of sustainable solutions & natural refrigeration technology