1. Phoenix Convention Center Phoenix, Arizona HVAC Re-tuning at GSA and Army Reserve Facilities: A Low-Cost Path to Energy Efficiency and Cost Savings Integrated Energy Low/No Cost Solutions through Building Automation System Control Technologies James Goddard and Danny Taasevigen Pacific Northwest National Laboratory August 13, 2015

2. Energy Exchange : Federal Sustainability for the Next Decade A systematic process to identify and correct building operational problems that lead to energy waste Implemented primarily through the building control system at no cost other than the labor required to implement May include small, low-cost repairs, such as replacing faulty sensors Includes identifying other opportunities for improving energy efficiency that require capital investment Might be thought of as a scaled-down retro- commissioning focused on identifying and correcting operational problems 2 What is Re-tuning

3. Energy Exchange : Federal Sustainability for the Next Decade Improve the building’s energy efficiency through low-cost and no-cost operational improvements (mostly through building controls) Identify opportunities to increase the building’s energy efficiency Adjust set points, schedules, economizer operations, etc. Identify system and equipment problems requiring physical repair Identify and pursue the big energy saving opportunities 3 Purpose of Re-tuning

4. Energy Exchange : Federal Sustainability for the Next Decade Major Focus Areas in Re-tuning – Occupancy scheduling – Discharge-air temperature control – Discharge-air static pressure control – Air-handling unit (AHU) heating & cooling – AHU outside/fresh air makeup – AHU economizer operation – Zone conditioning – Central plant Operations – Meter profiles 4 Re-tuning Process

5. Energy Exchange : Federal Sustainability for the Next Decade Army Reserve Command – Regional Energy Manager and local site staff – 2-3 buildings per site – Building types include office, drill hall, storage and maintenance – HVAC varies from packaged to built- up systems – Building occupancy hours vary from day-to-day, week to week with sporadic weekend use – O&M staff limited – May or may not have a BAS connected to HVAC equipment Programmable Thermostats possible – Whole building energy data sporadically available – BAS trend data and remote access difficult 5 Examples of Different Re-tuning Applications General Services Administration – Regional Energy Manager and local site staff – 1 building per site – Large commercial office buildings – HVAC almost always consists of built- up systems – Building occupancy hours fit typical commercial building office space (Monday through Friday 6:00 a.m. – 6:00 p.m.) – O&M staff consists of several positions (electrical, mechanical, plumbing, etc.). – Always have a central BAS connected to majority of HVAC systems – Whole building energy data almost always available – BAS trend data and remote access possible

6. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Model for the Army Reserve Army Reserve Re-tuning Steps – Pre-site visit Call with the Region Energy Manger and the local site staff Questions asked to the site staff and the energy manager – Ask for historical building control data – Building Control Vendor – HVAC equipment in the building – Problem areas – Level of access to the building controls – Does the staff use the building control system – Schedule a site visit 6

7. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Model for the Army Reserve Army Reserve Re-tuning Steps-cont. – Site visit Walk down the building Look at the HVAC equipment Look at the building control system Identify re-tuning measures Implement measures Train staff and energy manager on measures that are implemented Identify additional energy measures that can be turned into capital projects for the 7

8. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Model for the Army Reserve Army Reserve Re-tuning Steps-cont. – Post site visit Trip report Estimation of savings List of recommendations Project development 8

9. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Case Study for the Army Reserve Building Overview – Built within the last 5-7 years, 2-stories, 200,000 square feet – Used for the reserve command and as a training center on weekends – 24/7 operation of the HVAC equipment – Built-up air-handling units (AHUs) with variable-air-volume (VAV) boxes – Air-cooled chillers and hot water boilers with variable speed secondary loops – Full BAS integration of AHUs, chillers, boilers and VAV boxes Building Controls Review – Occupancy schedules did not work in the controls – Economizer dampers were not functioning correctly – Chillers were active during cool outdoor temperatures – AHU discharge-air temperature set points constant at 55°F – Constant AHU discharge static pressure sets points – Constant chilled water supply temperature set point Re-tuning Opportunities – Scheduling, static pressure reset, discharge-air temperature reset – Other? 9

10. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Case Study Results for the Army Reserve 10 Average daily electrical consumption before and after re-tuning show significant savings from re-tuning implementation Before re-tuning After re-tuning

11. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Future for the Army Reserve The Army Reserve Command understands the value in re- tuning Infrastructure limitations create difficulty with re-tuning process and sustaining re-tuning savings Adoption of Enterprise BAS System can enable continuous monitoring, analysis and reporting of Army Reserve buildings, as well as provide access for continuous re-tuning of control sequences. – Benchmarking – Trend analysis – Diagnostic Tools – Performance Dashboards – Monitoring of renewables 11

12. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Future for the Army Reserve 12

13. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Model for the GSA GSA Re-tuning Steps – Pre-site visit Screening evaluation to determine likelihood of re-tuning success Is the building likely to succeed (yes/no)? 13

14. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Model for the GSA GSA Re-tuning Steps Pre-site visit cont. – Call with the Region Energy Manger and the local site staff Review building history Review current energy use (based on utility bills) Discuss current and on-going energy projects Discuss problem areas in the building Plan trip logistics Provide BAS trending requirements list Remote BAS access (if possible) 14

15. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Model for the GSA GSA Re-tuning Steps Pre-site visit cont. 15

16. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Model for the GSA GSA Re-tuning Steps Site Visit – 2-3 days onsite – Review trend data/proposed measures—In-Briefing – Walk down the building – Review the BAS – Finalize proposed measures and discuss with site staff – Implement agreed upon control system measures with site staff (training) Monitor building response to implementation Start conservative with recommendations – Document all changes, before and after – Formal Exit Briefing 16

17. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Model for the GSA GSA Re-tuning Steps Post Site Visit – Deliver Interim Report to building and regional staff within 8 weeks of site visit which includes: Details on recommended measures and implemented measures Energy savings estimates for implemented measures and total for all recommended measures Monitoring plan for site staff’s troubleshooting and long-term monitoring of implemented measures – Post-site visit implementation call Discuss implemented measures, any issues or complaints, changes etc. Discuss plan for further implementation of measures that were not implemented onsite – Monitor BAS trends, interval meter data, and utility data for 6 months to validate re-tuning implementation and monitor other performance- related issues – Offer email/phone support to site staff as-needed 17

18. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Model for the GSA GSA Re-tuning Steps Post Site Visit-cont. – Deliver Final Report to building and regional staff after 6 month monitoring period which includes: Actual energy and cost savings from Targeted E4 efforts Pre and post Targeted E4 energy use intensity (EUI), and project EUI after 12 months 18

19. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Case Study for the GSA Building Overview – Built within the last 20 years, 16-stories, 600,000 square feet – Typical office building with courthouse space – Scheduled operation of the HVAC equipment (Monday through Friday 6:00 a.m. to 6:00 p.m.) – Built-up air-handling units (AHUs) with variable-air-volume (VAV) boxes – Water-cooled chillers and combination of condensing and non-condensing hot water boilers with variable speed secondary loop control – Full BAS integration of AHUs, chillers, boilers and VAV boxes Building Controls Review – Static pressure reset strategy had been overridden by operator (modified maximum and minimum limits to be equal) – Night setback strategy routinely started AHUs as early as 12:00 a.m. during the heating season – Optimal start strategy was configured for up to 4 hours of runtime prior to building occupancy Re-tuning Opportunities – Re-implement static pressure reset, modify night setback and optimal start strategies 19

20. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Case Study Results for the GSA 20 6 months after site visit, 12.6% whole building energy savings measured (8.6% electricity and 15.7% natural gas) 1.1 year simple payback for Targeted E4 at this building

21. Energy Exchange : Federal Sustainability for the Next Decade Re-tuning Future for the GSA The GSA has been an advocate for re-tuning for over 7 years, helping to improve the model Although Targeted Re-tuning for the GSA improves building efficiency and saves energy at a 1-2 year payback, long-term improvement of their energy portfolio will require more saturation – Current program covers 15-20 buildings per year Data-driven monitoring and diagnostics, although not required, helps to achieve optimal re-tuning results – Future direction may include data driven detection and automated re- tuning for basic principles – Site visits, training, and hands-on implementation currently offers the best results for re-tuning 21

22. Energy Exchange : Federal Sustainability for the Next Decade http://retuningtraining.labworks.org/training/lms/ 22 Re-tuning Training Materials

23. Phoenix Convention Center Phoenix, Arizona THANK YOU!! -- QUESTIONS? James Goddard James.goddard@pnnl.gov Danny Taasevigen Danny.taasevigen@pnnl.gov