Scope of Work. See for resources available

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Marcus Johns
8 years ago
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1 HVAC SWG Summary

2 Background Pool energy-efficiency knowledge Increase cost-competitiveness Develop resources aimed at assisting in reducing HVAC energy consumption Address barriers to energy-saving HVAC initiatives through collaboration and case studies Implement demonstration projects

reducing HVAC energy consumption Address barriers to energy-saving

3 Scope of Work Participating Companies Brainstorming Workshop Deliverables Site Assessments Literature Review URS Development Audit tool for HVAC System Operating costs for HVAC System Benchmarking Demonstration Projects Case Studies See for resources available

tool for HVAC System Operating costs for HVAC System Benchmarking

4 Site Assessments Management 19% Opportunity Frequency Distribution Air Change Reduction 20% Waste Heat Recovery 4% Ancillary Equipment 14% Setpoints 14% Schedule Optimisation 6% Maintenance 3% Heating Cooling Issues 3% Design 14% Controls 3%

Ancillary Equipment 14% Setpoints 14% Schedule Optimisation

5 Savings Potential Opportunity Savings Potential Waste Heat Recovery 8% Setpoints 9% Management 1% Air Change Reduction 31% Schedule Optimisation 16% Maintenance 1% Heating Cooling Issues 10% Design 4% Controls 2% Ancillary Equipment 18%

Reduction 31% Schedule Optimisation 16% Maintenance 1%

6 Where do I start?!!!!!!!!!!!!!!!

7 Where to start Energy Service Requirements ACPH Temperature Humidity Controls Operation / Maintenance Management Etc.

8 Top 3 Opportunity Categories Understanding of Energy Service Requirement Optimum HVAC Control Efficient Operation and Manintenance

9 Energy Service Requirement What is the HVAC system for? Temperature requirement Humidity Requirement? Do we need humidity control? % Fresh air Does the original design intent still hold true? Know the factor of safety. (To be sure to be sure?)

10 Control What drives the HVAC system? Are we operating at 100% all the time Consider demand control ventilation. (System operating the same with only security in the building) Consider floating setpoints. Consider different control strategies for HVAC system. Look at other services servicing the HVAC system. Chillers LTHW steam compressed air etc.

(System operating the same with only security in the building) Consider floating

11 Controls Understand the consequences of differing control strategies from an energy viewpoint 6 different strategies simulated Fixed and floating parameters Temperature Humidity Fresh Air / Return Air % Full Fresh Air (Strategies 1 and 2) 15% Fresh Air (Strategies 3 and 4) Modulating Dampers (Strategies 5 and 6) No Deadband Deadband Percentage Reduction 12,161 9, % 9,352 5, % 5,060 3, %

Air % Full Fresh Air (Strategies 1 and 2) 15% Fresh Air (Strategies 3 and 4) Modulating Dampers

12 Energy Consumption (kwh) Controls Energy Consumption Comparison 250, ,000 Electrical Energy Thermal Energy 150, ,000 50,

13 Operation and Maintenance Significant potential for energy wastage in operation and maintenance. Checklist currently being developed in Spin III Valves passing. Set points changed Filters blocked Systems in operation unnecessarily Lack of understanding of the consequences of changes to operation.

Checklist currently being developed in Spin III Valves passing.

14 Look inside and outside the box Space Condition not an indication of efficiency

15 Maintenance Hidden energy losses Recognise the consequences of mechanical failure or calibration requirements Check chilling load in winter and boiler load in summer

16 Effective Maintenance Maintenance Activities Insulate supply ducts Opportunity Discussion Action Typically supply ducts should be insulated on all new systems. Change filters when recommended maximum differential pressure is exceeded Check AHU control sensor calibrations as part of annual maintenance Repair passing control valves Repair Passing Heating Coil Valve Repair Passing Cooling Coil Valve Repair passing reheat batteries Time based activities have historically been selected but the marginal efficiency loss is negated by replacement costs From an energy standpoint the instrumentation that can significantly affect energy usage should be put on a calibration schedule Review operation of heating and cooling valves periodically for "tightness" and correct positioning Review valve operation via observations on BMS, temperature profiles across units etc to ensure correct operation. Insulate ducts to appropriate standards Modify maintenance activities to condition based maintenance as opposed to time based where appropriate. Review instrumentation calibration requirements and add to calibration schedule as appropriate Repair or calibrate identified faulty valves Identify valves and repair / replace as appropriate

Valve Repair Passing Cooling Coil Valve Repair passing reheat batteries Time based activities have historically been selected but the marginal efficiency loss is negated by replacement costs From an

17 Benchmarking Pharmaceutical Benchmarking LIEN Benchmarking Like for Like comparison (Internal benchmark preferable)

Analysis of HVAC Control Strategies

PUBLICATION DATE: Q1 2009 REF NUMBER: HVAC SWGII 006 03 HVAC SPECIAL WORKING GROUP Analysis of HVAC Control Strategies 06 Table of Contents 1 Introduction 2 2 Scope 3 3 Analysis 4 3.1 Strategy 1 4 3.2