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Realising energy savings: a practical guide to understanding, specifying and operating building control systems . Name of Presenter: Dr. Andy Lewry Date: April 1st 2014. Building Research Establishment A world leading centre of expertise for the construction industry providing: Research
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Realising energy savings: a practical guide to understanding, specifying and operating building control systems Name of Presenter: Dr. Andy Lewry Date: April 1st 2014
Building Research Establishment A world leading centre of expertise for the construction industry providing: • Research • Consultancy • Information services to customers worldwide
Our Staff… • Over 650 staff • Over 400 professionally qualified • Many national and international experts • An integrated team of professionals …people at the heart of our business
BRE’s experience in Energy Efficiency • 40 years experience since 1970’s oil crisis • 100 professionals working on all aspects of EE in construction • Developed UK Government’s Best Practice programme • Represent UK on concerted action • Demonstration projects and testing on-site • European and international standard work • Modelling team producing UK Govnt software • Rolled out experiences to several other countries – currently working in the Balkans rolling out the recast EBPD in Croatia, Serbia, FYI Macedonia, Kosovo and BiH - Federation. • Training and CPD courses • Certification schemes to accredit professionals • Certification services
Today’s agenda • Why manage energy? • Control systems available • The specification of controls and control systems • Functionality – must be linked to a servicing strategy • Understanding your needs as an end user • “10” key issues to address
Why managed Energy? Business drivers • Security of supply • Rising costs • Wastage and good management practice • Green Credentials • Legislation
Why managed Energy? Life costs of a building • Energy is 40% of running costs • Need to manage this effectively • Controls are essential • Need a strategy - Demand based control is the most energy efficient
Control systems available • Building Management System (BMS) • Building Energy Management System (BEMs) • Demand Control or zone control • Sequencing • Weather compensation • Boiler load optimisation • Occupancy controls • Variable controls • Interlock controls
Performance of controls • Can be assessed by BS EN 15232:2012
The specification of controls and control systems Building regulations • Underpinned by the advice given in Approved Document L (ADL) or Part L • Standards laid out in the Non-Domestic Building Services Compliance Guide (NDBSCG) • Provides suggested minimum requirements • Controls package for each technology area and application • Proposed that controls meet the requirements of Class C of BS EN 15232:2012 Therefore, basic functionality required to operate a building but not necessarily in the most efficient manner.
UK’s Enhanced Capital Allowance (ECA) scheme (1) • Tax break on investments in certain energy saving equipment • The scheme is underpinned by the Energy Technology List (ETL) - https://etl.decc.gov.uk/etl/site.html • Currently has criteria for: • Heating, Ventilation and Air Conditioning (HVAC) controls (now Building Environment Zone Controls); • Hot Water Systems Optimising controls (now Heating Management Controllers); • Lighting controls; and • Variable Speed Drives (VSDs).
UK’s Enhanced Capital Allowance (ECA) scheme (2) • Building Environment Zone Controls • Control the environmental conditions (i.e. temperature, ventilation rate and/or air condition) • In individual zones (i.e. rooms or areas) within a building • They can be programmed to maintain these environmental conditions within pre-set limits in a manner that takes into account: • Occupation schedules • Occupation status and/or level of activity in the zone • Environmental conditions, and the specific operating requirements of the zone
UK’s Enhanced Capital Allowance (ECA) scheme (3) Building Environment Zone Controls Covers four categories of products: • Standalone control units • Centralised control units • Packaged control products • ‘Add-on’ control modules
UK’s Enhanced Capital Allowance (ECA) scheme (4) Building Environment Zone Controls • Has in-depth criteria • When all imposed represents good practice • Pre-programmed BEMs would qualify • Falls short of best practice because: • No Summer /winter change over • Requirement for 365 day programming, as defined in BS EN 15500 has been excluded • Probably Class B of BS EN 15232
Best practice Functionality – must be linked to a servicing strategy • For example Demand control • Adapts the standard assumption on occupancy and follows actual occupancy patterns • All building services can be controlled to meet peak loads and occupancy levels – in normal operation these conditions rarely occur • Typical occupancy patterns are provided in BS EN 15232 • for a range of building types • it defines classes of energy efficient controls which can obtain that degree of control.
Best practice Class C - Standard operational characteristics of buildings
Best practice Class A – High energy performance controls systems
Pre-programmed BEMs • Stand-alone products • Use a fixed set of functions • Normally expandable, so size is not limited • If installed with sensors, fan speed inverters and dampers they can perform functions such as Demand Control Ventilation (DCV) functions and realise significant savings • Only suited to small installations • the complexity of many HVAC systems and the desire to include several renewable technologies in the mix of primary plant makes use of fixed control functions very limited
Best practice - Programmable BEMs • Programmable versus Pre-programmed BEMs • Programmable controllers offer significant energy saving advantages over pre-programmed controllers due to their greater flexibility • Programmable BEMs • Can perform a wide range of control strategies • Offer the ability to control all building systems • Have the ability to maximise the overall energy saving potential • Give flexibility which ensures that as plant is changed / upgraded the control system can be modified to suit • Reduces the chance of the control system becoming redundant by a change in usage or having a short lifetime. • Can be applied to all applications regardless of size • Programming has become easier • Costs are reducing
Understanding your needs as an end user • Understanding your business (1) • Business’s objectives over the next 3 to 5 years? • First point in establishing a Servicing and Controls Strategy • Is your business expanding in size? • Will more space be required? • Will additional staff require more heating or cooling? • How will this be monitored or controlled? • Will partition walls be installed to create meeting rooms or offices – how will this impact on the existing HVAC and the current controls • Will operating hours change? • How do you ensure the plant is operating when it needs to? • Can the current controls cope with this? • Can multiple shifts in production be accommodated by your current controls? • What is the plan with your business’s estate? • How long is left on the lease? • Will you be relocating to larger or smaller premises – this will focus your investment case on whether to invest or not.
Understanding your needs as an end user • Understanding your business (2) • Does your business have the skill set or expertise to manage and control the building controls? • Do you need pre-programmed controls or programmable controls? • Is senior management committed to reducing energy costs or/and carbon emissions? • If not it may prove difficult to get buy-in at a senior level • Deals with management issues • Understanding your building and estate • What do you have? • Where are they? • Conduct an audit of energy usage • Which areas need controls • What areas need: • Maintenance • Upgrades • Investments • Build business cases
Understanding your needs as an end user • Understanding your business (3) • Sustainability and redundancy • Integration • Utilise what is already there • More than one control? • Look after it • Continuous commissioning • Planned maintenance
“10” key issues to address • Specification breaking – procurement routes and “Value engineering” • Occupancy patterns – schedules and density • Future proofing – flexibility and upgrades • Links to Monitoring and Targeting (M&T) – optimisation systems • Verification/certification • Commissioning – initial set-up and an on-going process • Training • Maintenance requirements – planned upgrades • Management reporting • Additional functionality – critical services/alarms etc.
Conclusion • Controls are a powerful tool • run buildings efficiently • provide the desired environment for the occupants • With technology becoming cheaper and advancing more quickly, control systems need to be: • Flexible • upgradable • have the facility to easily communicate and integrate with other systems • Programmable Building Energy Management System (BEMs) would appear to offer the best solution in trying to achieve all these objectives
Questions? Dr Andy Lewry lewrya@bre.co.uk +44 (0)1923 66 4359 Visit http://www.bre.co.uk/page.jsp?id=1790 • Publisher: IHS BRE Press • Publication date: 17 Jan. 2012 • Reference: FB 44 • ISBN: 978-1-84806-235-1