TOP 10 STRATEGIES FOR NEW AND EXISTING BUILDINGS

Transcription

1 TOP 10 STRATEGIES FOR NEW AND EXISTING BUILDINGS Kristine Chalifoux Management Engineer Facility and Services, University of Illinois Big10 & Friends October 10, 2016

2 WHAT IS HIGH PERFORMANCE DESIGN? What will it take to achieve high performance? A. Goal Setting: design & performance energy goals Know where you are and where you want to go. B. Pick the right team: identify an energy champion C. Focus on energy: in design & construction Know the most effective strategies D. Verify energy goals: model & measure E. Plan to maintain: training & ongoing verification 2

3 ENERGY USAGE ANALYSIS Obtain at least one year s worth of energy data on the building (two years or more is better). Plot the energy consumption for each month versus heating degree days and cooling degree days. Review the graphs for anomalies. KWH 25,000 20,000 15,000 10,000 5,000 kwh CDD CDD - July Aug Sep Oct Nov Dec Jan Feb Mar Apr May June 5,000 4,000 3,000 THERMS 2,000 1,000 HDD July Aug Sep Oct Nov Dec Jan Feb Mar Apr May June Therms HDD

4 TWO TYPES OF BUILDINGS? Envelope Dominated: energy usage pattern tied to the climate, generally with some base load electrical and natural gas usage. Internal Gain Dominated: energy usage pattern only slightly or not linked to the climate. Cooling load year-round. Typically, small buildings are envelope dominated and large buildings are internal gain dominated although this is not cast in concrete.

5 MAKEUP/VENTILATION DOMINATED Buildings which have high ventilation or makeup air loads such as classrooms and laboratories. Similar to Internal Gain, but loads are based on mechanical requirements, not processes. Energy used to condition outdoor air for ventilation dwarfs the energy consumed by lighting, plug loads, and general conditioning. Energy Use - kbtu vs CDD 3,000, ,500, ,000, ,500, ,000, , SEP NOV JAN MAR MAY JUL SEP NOV JAN MAR MAY JUL SEP UIUC CW UIUC Steam UIUC Elec UIUC Elec2 CDD Energy Use - kbtu vs HDD 3,000, ,500, ,000, ,500,000 1,000, , SEP NOV JAN MAR MAY JUL SEP NOV JAN MAR MAY JUL SEP -800 UIUC CW UIUC Steam UIUC Elec UIUC Elec2 HDD

6 TOP 10 STRATEGIES NEW AND EXISTING BUILDINGS 6

7 TOP TEN ENERGY STRATEGIES Form & Environment 1. Orientation & Form 2. Insulation 3. Air Sealing Loads EXTRA CREDIT: After implementing all of these, consider renewables such as solar and wind. 4. Lighting 5. Loads Heating, Ventilating, & Air Conditioning 6. Heating 7. Cooling 8. Motors & Pumps 9. Building Automation 10. Commissioning

8 CASE STUDY Electrical and Computer Engineering (ECE) Building Classrooms, labs, office, etc 230,000 sf

9 ORIENTATION & ENVIRONMENT Orient buildings on the eastwest axis (+/- 10 ) Reduce west facing glass Shade south glazing Take advantage of, or block, prevailing winds Orientation makes a difference in energy use!

10 CASE STUDY ORIENTATION East West Axis South overhangs Northern and southern windows 30% glazing Passive solar system helped reduce energy use 55%

11 ORIENTATION DON TS Curtain wall

12 ORIENTATION DON TS Curtain wall JUST SAY NO!

13 ORIENTATION DON TS faces west Beware of value engineering! Shading devices compensate for the heat gain from large banks of windows, only to be eliminated later in order to cut up-front costs. If the windows themselves are not redesigned, the result is visual discomfort from glare and higher energy costs.

14 ENVELOPE Exceed code Wall and roof insulation levels Continuous insulation Windows Percent of wall area Low-e coating Reduced infiltration Air sealing Air barrier Vestibules Envelope commissioning

15 SEALING THE ENVELOPE Wall to Roof Junction Air Sealing Air infiltration is unwanted air flow into and out of the building caused by leakage paths and pressure differences between inside and outside of the building. Pre-Retrofit Post Air Sealing Openings at the top and bottom of the building are the most important to seal. Door weather stripping! Current condition

16 STACK EFFECT Don t let this happen to your building! Positive pressure (with reference to outside) Neutral pressure plane Negative pressure (with reference to outside) Photo Credit: David Keefe, Vermont Energy Investment Corporation

17 CASE STUDY ENVELOPE R-18 to R-24 walls Typical wall 8 CMU, air barrier, 4 polyiso, 4 terracotta rain screen R-30 roof Reflective white roof 4 continuous insulation (polyiso) Windows 30% glazing U-0.28 SHGC-0.27 Visible transmission 64% Account for 3% of savings

18 ENVELOPE DON TS Building in southern Illinois Built in 2005 Designed to code Occupants were cold No continuous insulation Don t underestimate the impact of thermal bridging

19 MORE ENVELOPE DON TS Avoid these common pitfalls Assemblies with significant thermal bridging 19

20 MORE ENVELOPE DON TS Avoid these common pitfalls Assemblies with significant thermal bridging 20

21 MORE ENVELOPE DON TS Avoid these common pitfalls Missing insulation in installed assemblies 2. What they got 1. What they drew 21

22 LIGHTING 22

23 LIGHTING 23

24 LIGHTING Lighting power usage Reduce ASHRAE numbers <0.9 W/sf Occupancy & vacancy sensors Manual On / Auto OFF (after less than 30 minutes) Multi-level switching or dimming Daylighting controls Follow ASHRAE 90.1 for controls

25 MULTI-LEVEL CONTROLS AND SWITCHING Image: LaMar Lighting Now required in ASHRAE 90.1!

26 LED RETROFIT Interior retrofit of HID. Energy savings Maintenance savings Better lighting Eventual phase out of T8 Smaller energy savings Some maintenance savings Better lighting control LED Parking lot fixtures mainly save energy by having better directionality. Savings of 50-60% are typical. There is also potential for motion sensors, photo cells, and dimming. Image from Lutron Image from Vanguard

27 LIGHTING DON TS Avoid these common pitfalls Missing or inadequate controls labeling Lighting controls too complicated for users & maintenance staff Control system not programmed, staff not trained 27

28 CASE STUDY LIGHTING Lighting Power Density = 0.9 W/sf Daylighting controls on perimeter windows Clearstories to bring light deeper into spaces Louvered sun shade Vacancy sensors and occupancy sensors throughout Mix of LED and fluorescents

29 PLUG LOADS Use design to reduce loads ASHRAE % receptacle control Data Centers is this feasible? Cold Aisle Server Virtualization Thin Client Economizers General Plug Loads Smart strips Process: Equipment efficiency Equipment interaction (i.e. reclaim heat) ENERGY STAR equipment From Keyzone.com

30 CASE STUDY PLUG LOADS A 4,000 sf clean room uses approximately 22% of all building energy and only occupies 3% of the building floor area! Premium high efficiency motors Variable-speed drives ENERGY STAR appliances and equipment VAV fume hoods with energy recovery Public stairs to encourage use Computer energy management User interfaces and extensive metering.

31 HVAC Minimize loads first, then select & size equipment Adding quality to envelope and loads reduces the final HVAC size and cost. Choose High efficiency systems/ equipment Air source heat pumps Condensing boilers Chilled beams Variable refrigerant flow (VRF) Modular equipment Choosing the right system(s) An efficient system: Integrates with the design concept Matches planned use and zone control Has a manageable level of complexity Is scalable for varying demand Is easy to maintain Is easy to control

32 HVAC DEMAND CONTROL VENTILATION Reduce loads from ventilation Demand control ventilation Tie to lighting controls? Graphic from: EnergyCodes.gov

33 CASE STUDY HVAC Chilled beam system for cooling of the classrooms, offices, labs and corridors Displacement ventilation in the lobby and large auditorium Heat recovery chillers with net metering Heat recovery wheels Water cooling loop to cool lasers and electronic equipment in labs

34 CASE STUDY HVAC STORAGE 25 million liter water thermal storage in campus chilled water system Energy used as needed throughout the campus Capacity: about one hour of total campus load with just a 1 C temperature change.

35 HVAC Avoid these common pitfalls Equipment selection based on first-cost only Failure to right-size equipment based on final building envelope configuration and energy efficiency measures implemented Lack of system commissioning Cramped mechanical rooms Inadequate operator training Poor system zoning 35

36 BUILDING AUTOMATION SYSTEMS (BAS) Great potential No other system has greater potential to determine the success (or failure) of an energy-efficient building project than the selection, installation, and commissioning (or lack of commissioning) of HVAC controls. Can make or break a successful LEED project

37 BUILDING AUTOMATION SYSTEM (BAS) Ability to control and document systems and settings Design to the level of ability of operating personnel Assure adequate training and ability to manipulate System should Allow owner to set schedules for equipment and lighting Optimal equipment start with adaptive learning Time and respond capabilities based on demand in zones Monitor and meter energy use Reset schedules for systems Trend data Send alarms Not this: Sometimes people need/ want this:

38 BUILDING AUTOMATION DON TS Community college in southern Illinois Had a BAS, were never trained on how to use it Needed to call BAS contractor anytime there was a malfunction so, typically didn t bother to call. For each adjustment: $180/hr * 4-6 hrs = proposal + 3hrs travel time $180/hr * 4-11 hrs = work completed + 3 hrs travel time $1,440 - $4,000!

39 COMMISSIONING A quality assurance process Occurs between early design phase through occupancy Ensures that the building operates as intended Building staff are prepared to operate and maintain Why is it needed? Increasing complexity of building control systems Lack of contractual coordination between trades Technical staff in the field who looks out for the owner

40 CASE STUDY COMMISSIONING Commissioning agent brought on to project during schematic design phase On-site commissioning of all equipment Trained staff on equipment and control operation Ongoing commissioning

41 COMMISSIONING DON TS Back to our poor building Designed with a BAS but was never commissioned Uses 3x energy as planned

42 RETRO-COMMISSIONING EXAMPLE SITE AND BILLS Sep09-Aug10 Annual Consumption Annual Costs Average Unit Cost 2001 High School Standard construction Constant volume system Standard efficiency boilers Ran out of money on the energy budget Electric Energy Electric Demand Natural Gas 2,041,200 kwh $106,176 31% $0.05 $/kwh kw (min-max) $88,812 26% $16 $/kw 165,094 therms $145,097 43% $0.88 $/therm Total $340,085 Floor Area 117,000 sf Occupants 300 Students, 55 Staff Electricity Use Intensity 17.4 kwh/sf/yr Gas Use Intensity 1.41 therms/sf/yr Energy Use Intensity 201 kbtu/sf/yr Energy Cost Intensity $2.91 $/sf/yr Sept 07 - Aug 08 EUI Sept 08 - Aug 09 Sept 09 - Aug 10 Targe Finder KBTU/SF/YR

43 Electricity (kwh) BILL ANALYSIS 300, , , , ,000 50,000 On-Peak kwh Off-Peak kwh Cooling Degree Days SBHS: Monthly Electricity Usage 2008 had summer school Some anomalies in 2007 Fairly high spring and fall baseload 0 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 Jun-08 Aug-08 Oct-08 Dec-08 Feb-09 Apr-09 Jun-09 Aug-09 Oct-09 Dec-09 Feb-10 Apr-10 Jun-10 Aug-10 Oct-10 Dec-10 Feb-11 Apr-11 Jun-11 Aug-11 Oct-11 Dec-11 Feb-12 Apr-12 Jun-12 Aug-12 Oct-12 Dec-12 25,000 Therms Heating Deg Days SBHS: Monthly Gas Usage 20,000 15,000 10,000 5,000 0 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 Jun-08 Aug-08 Oct-08 Dec-08 Feb-09 Apr-09 Jun-09 Aug-09 Oct-09 Dec-09 Feb-10 Apr-10 Jun-10 Aug-10 Oct-10 Dec-10 Feb-11 Apr-11 Jun-11 Aug-11 Oct-11 Dec-11 Feb-12 Apr-12 Jun-12 Aug-12 Oct-12 Gas Use (therms) HDD line is a relative indicator of gas use Notice pretty good seasonal dependency

44 Electricity (kwh) BILL ANALYSIS 300,000 On-Peak kwh Off-Peak kwh Cooling Degree Days 250, , , ,000 50,000 SBHS: Monthly Electricity Usage Then, things went crazy. 0 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 Jun-08 Aug-08 Oct-08 Dec-08 Feb-09 Apr-09 Jun-09 Aug-09 Oct-09 Dec-09 Feb-10 Apr-10 Jun-10 Aug-10 Oct-10 Dec-10 Feb-11 Apr-11 Jun-11 Aug-11 Oct-11 Dec-11 Feb-12 Apr-12 Jun-12 Aug-12 Oct-12 Dec-12 25,000 Therms Heating Deg Days SBHS: Monthly Gas Usage 20,000 15,000 10,000 5,000 0 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 Jun-08 Aug-08 Oct-08 Dec-08 Feb-09 Apr-09 Jun-09 Aug-09 Oct-09 Dec-09 Feb-10 Apr-10 Jun-10 Aug-10 Oct-10 Dec-10 Feb-11 Apr-11 Jun-11 Aug-11 Oct-11 Dec-11 Feb-12 Apr-12 Jun-12 Aug-12 Oct-12 Gas Use (therms)

45 BILL ANALYSIS SBHS: Monthly Electricity Usage 300,000 On-Peak kwh Off-Peak kwh Cooling Degree Days Now it is fixed. 250, , , ,000 50,000 0 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 Jun-08 Aug-08 Oct-08 Dec-08 Feb-09 Apr-09 Jun-09 Aug-09 Oct-09 Dec-09 Feb-10 Apr-10 Jun-10 Aug-10 Oct-10 Dec-10 Feb-11 Apr-11 Jun-11 Aug-11 Oct-11 Dec-11 Feb-12 Apr-12 Jun-12 Aug-12 Electricity (kwh) Oct-12 Dec-12 25,000 20,000 Therms SBHS: Monthly Gas Usage Heating Deg Days 15,000 10,000 5,000 0 Feb-07 Apr-07 Jun-07 Aug-07 Oct-07 Dec-07 Feb-08 Apr-08 Jun-08 Aug-08 Oct-08 Dec-08 Feb-09 Apr-09 Jun-09 Aug-09 Oct-09 Dec-09 Feb-10 Apr-10 Jun-10 Aug-10 Oct-10 Dec-10 Feb-11 Apr-11 Jun-11 Aug-11 Oct-11 Dec-11 Feb-12 Apr-12 Jun-12 Aug-12 Oct-12 Gas Use (therms)

46 EXTRA CREDIT: RENEWABLES Only consider renewables after implementing all of the previous ideas The cost per unit energy saved of high efficiency equipment and improved design is less than the cost per unit of energy of wind or solar Renewables do, however, make great marketing and educational opportunities and can be more affordable when incentives are available

47 EXTRA CREDIT Renewables: Plan the infrastructure now for future Select site-appropriate technologies Use to take last step to net-zero 47

48 CASE STUDY RENEWABLES Infrastructure added to building for future installation. Projected generation of about 50% of energy requirement Paired with solar panels on nearby garage to bring building to net zero!

49 CASE STUDY SUMMARY 50% less energy than ASHRAE Total 167 kbtu/sf/yr Actual total annual energy use approx 17,000MMBtu 3,000,000 2,500,000 2,000,000 1,500,000 1,000, ,000 0 Energy Use - kbtu UIUC CW UIUC Steam UIUC Elec UIUC Elec2

50 QUESTIONS 50