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High Performance Building Guidelines 2nd Edition
JHU High Performance Building Standards
Introduction This guide was assembled with input from each of the Johns Hopkins University’s Schools, Divisions and Campuses. It will assist designers, project managers and maintenance technicians to improve sustainable energy designs, their implementation and operations. This will more clearly communicate our energy and water reduction goals for construction, building materials, equipment and systems, and operational and maintenance needs to both internal stakeholders and to our design consultants. The Office of Sustainability has collaborated with our campus Design and Construction, Project Management and Facilities Operations staff to identify areas needing improved sustainable choices. Improving our sustainable efforts challenges each of us to identify and implement the most environmentally friendly, financially sound and socially acceptable solutions for our institution. These initiatives will reduce our Greenhouse Gas emissions, water consumption and waste generation. Many of these opportunities will result in more efficient buildings, equipment and systems, intended to save energy and operating expenses. No initiatives should compromise the user’s comfort, productivity or safety. Questions or comments about this guide? Please contact Ed Kirk, the University Energy Manager at 443-‐997-‐2343 or
[email protected].
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JHU High Performance Building Standards
Table of Contents 1.
2.
3.
4.
5.
6.
7.
8.
Guiding Principles a. Using this Guide b. Energy Reduction c. Greenhouse Gas Reduction Goals d. LEED and Building Energy Codes Tools and Benchmarks a. Financial Evaluation b. Metering & Measuring Performance c. Energy Modeling d. Audits and Inspections e. Commissioning f. LEED, Energy Star, IGCC and Energy Code g. Utility Incentives and Rebates Building Envelope a. Roofing b. Windows and Doors c. Thermal Insulation Mechanical Equipment and Systems a. Heating and Hot Water b. Ventilation and Cooling c. Domestic Water d. Elevator e. CHP f. Controls (BAS, BMS, ATC, EMS) g. Dashboards Electrical Equipment and Systems a. Service, Transformers and Distribution b. Emergency Power c. Lighting d. Lighting Controls e. Plug Loads Specific Space Types a. Data Centers b. Research spaces c. Cooking Facilities d. Mechanical and Electrical spaces e. Tel/Data Closets f. Mobile Equipment Renewable Energy a. Solar PV b. Solar Thermal c. Wind d. Bio Fuels References
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JHU High Performance Building Standards
Guiding Principles Using this Guide: The information contained here is intended to apply to all projects that touch building systems that consume energy or water, regardless of project budget or square foot impact. Using progressive ways of providing for capacity, redundancy, reliability and future flexibility, so every project or renovation moves JHU toward its overall goals. Verify through proper installation, set-‐up and commissioning that the thermal envelope and all building components and systems are working optimally. Energy & Water Reduction Goals: Each project should set a goal to be designed to use 30% less energy and water than allowed by the latest published codes. Projects effecting energy use should perform some sort of energy modeling and use Life Cycle Cost Analysis, when possible, to compare project options, enabling design teams to make informed decisions. All project options that pay for themselves in less than half their life expectancy should be brought to the design team’s attention for serious consideration. This means that financial analysis that considers total cost of ownership (Life Cycle Cost Analysis) must be performed. Do not allow systems to become overly complex, costly to install or difficult to maintain. Build in the ability for automatic tune-‐ups, fault detection and performance verification using “dashboards” and smart phone apps. Ensure a healthy, productive and safe environment for the building’s occupants. Greenhouse Gas Reduction: Our University goal to reduce our GHGs by 51% by 2025 need to be measurable. Real-‐time metering is required on all energy and water systems to regularly verify performance and progress toward our reduction goals. LEED and Building Energy Codes: We wish to create the healthiest, most productive work environments possible. When conflicts occur between building and energy code requirements, we insist upon open dialogue amongst the design team and the JHU owner representatives so we are sure we are meeting the end user’s needs, the intent of the codes and not just the letter of the codes.
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JHU High Performance Building Standards
Tools and Benchmarks Financial Evaluation: Energy code enhancements have forced designers and operators to pay more attention to project budgeting. Even more important than a project’s initial design and construction funding, and regardless of size, are energy code limits and impacts to operating costs over their expected life. While the use of first cost estimating is a simple tool when developing initial project budgets, today’s budgets must include energy code compliance. Life Cycle Cost Analysis must be used for “Value Engineering” cost cutting options that could impact energy and water use, storm water mitigation or other long term environmental factors. Measuring Performance: Each building requires utility metering to track energy and resource use. At a minimum metering is required for electrical, gas, oil, water, steam and chilled water. For new construction and major renovations, and where applicable to major alterations to the system infrastructure, sub-‐metering is also needed on domestic hot water make-‐up, irrigation, cooling tower, boiler make-‐up, gray water system inputs, lighting, HVAC and building equipment, and plug loads. Energy Modeling: Full modeling is required for all new construction and major renovations. Some energy modeling is also required for any renovations that alter mechanical or electrical systems. Energy modeling should reflect how the spaces and systems will operate once occupied. Models are the tool needed to perform Value Engineering or for obtaining utility rebates. The Energy Use Intensity (EUI) calculation from energy model will be compared to similar space use types. If planning a renovation, model should show existing pre-‐renovation consumption, the latest ASHRAE 90.1 code limit and estimated post-‐renovation consumption. Listed below are some Energy Use Intensities (EUI) in site KBTU/gsf/yr. This table will assists the design team to understand what limits exist to beat JHU’s goal of 30% less energy use.
Building Type
JHU ’09 Avg EUI
ASHRAE 90.1 2010 JHU 30%. Surface should strive for 3 year aged Solar Reflective index of > 64 per ASTM E 1980. When re-‐roofing we ask that the following considerations be met: • • • • • • •
Roofing system minimum value of R-‐30, except within 3 feet of roof drains. Roofing have a minimum pitch of 1/4 inch per foot and zero standing water. Minimum curb and flashing heights of 9 inches. The entire roofing system have an expected life (not to be confused with warranty) of 30 years. The roof design and equipment lay-‐out will allow for renewable energy, storm water mitigation or heat island mitigation. The roof can withstand foot traffic of typical tradesmen, severe weather events and bird activity without reducing it's life. Tear-‐off must be recycled and new roofing system must use sustainable and recyclable materials.
Exterior walls average insulation R-‐20 including window and door values. Windows and Doors: Storefronts and Glazing with a • • • •
low E 30% loading. Upsize distribution wiring where appropriate. Include harmonics mitigation plan. Peer review of EE design by power system optimization expert. Perform electrical audit and correct identified load and harmonics deficiencies one year after spaces have been occupied. Transformers: Use only energy efficient ones rated for digital/electronic loads with harmonic mitigation. Ensure they are phase balanced and loaded to minimum 30% of rated capacity off peak and 50-‐70% during occupied times. Measure loads once spaces are fitted out and spaces are occupied, but no later than 12 months after Substantial Completion. Correct or replace oversized transformers as needed. Since 2008 transformers must meet NEMA TP-‐1 standards for energy efficiency. The transformers must also meet the DOE’s CSL-‐3 energy efficiency standards and have harmonic mitigation features. Transformers must have full rated efficiency at 1/6 load. Specify transformers so they operate at 50% or higher load when the building is fully occupied and meet the intent of NEC. Remember, transformers are designed to be loaded to 110-‐120% for short durations (an hour or less) and work best in the 70-‐90% range. Bottom line, the more the EE designer knows about the electrical equipment and loads being served by the transformer the better job they can do designing for most efficient and reliable operation. Electrical Distribution: Control or mitigate system harmonics. Emergency Power: Use Natural Gas generators for all future installations with BACT to allow for optimizing their use beyond just power outages. Consider CHP units and fuel cells for this role when performing your LCCA. Consider energy efficiency when choosing equipment and components (crank case heaters, thermal recovery, electric conversion, etc.) 12
JHU High Performance Building Standards
Lighting: Employ day light into >75% of occupied spaces, use Sola-‐tube for interior spaces where possible. Consider Photo-‐Luminescent Exit Signs. Use only LED lighting and with efficacy > 100 lumens/watt. Use fixtures that deliver proper light levels efficiently to the work surface. Use the best qualities of light possible. Do not over illuminate spaces. Use dark sky compliant designs for interior and exterior lighting. Use lighting layouts with the lowest watts/square foot to meet work surface light levels. Provide photometric calcs for all spaces. Move day light to work spaces with enhanced window use and with effective use of light tubes or skylights (Solatubes preferred) Lighting Controls: Provide a detailed sequence of operation and schematic on drawings for easy interpretation of installing contractor. Provide occupancy lighting control (100% of facility spaces) and step dimming (vacancy controls) in office, meeting, classroom and similar spaces. Automatically control artificial light output anywhere glazing, skylights or Sola-‐tubes exist. Automatically turn lights and equipment off when no occupants are present. DOE recommended Lighting Power Density (watts/sf) targets (2012) and desired foot candle levels. Goal: to achieve 30% better than ASHRAE 90.1 2010 and IES 2012
w/sf
F.C. base
F.C. max
F.C. Unocc
Office (off, 50%, 100%)
0.7
20
30
0
Conference/Meeting Room
0.8
20
35
0
Corridor
0.45
10
15
0**
Restroom
0.4
10
15
0
Mechanical Room
0.5
10
15
0.5*, ***
Stairwell
0.45
10
15
0*
Lobby
0.35
10
20
0**
Research labs (Labs 21)
1.4
50
75
0
Classroom/lecture hall
0.7
20
30
0
Dining
0.6
5
20
0
Auditorium
0.7
5
20
0
Parking/Garage
0.2
1
1.5
0.5*
Residence
0.6
20
30
0
Athletic spaces
1.0
25
65
0
Exterior Walkways
0.7/lf
1
5
1
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JHU High Performance Building Standards
* Occ sensors on individual fixtures recommended. Total darkness not recommended for retrofits. ** Some night lighting may be allowed for a “welcoming” experience when approaching these areas. *** Fail safe Occ sensors should be used for lighting around mechanical or electrical equipment.
Electric Hand Driers or Paper Towels? If electric hand driers are used, they must effectively dry hands in 0.5MW. Ensure design choices to meet capacity, reliability and redundancy do not reduce operational energy efficiency. Research Spaces: Follow guidelines in Labs 21 and High Performance Labs. Use occupancy controls for lights and air flow. Design research spaces for six air changes occupied and four when unoccupied and under negative pressure to the adjacent spaces. Monitoring for toxic compounds can allow as low as two air changes when unoccupied by controlling supply and exhaust air accordingly. Use only ultra-‐high 14
JHU High Performance Building Standards
efficiency or high performance fume hoods and chemical storage cabinets. Retrofit existing fume hoods with baffles and recertify to perform to today’s VAV High Performance standards. Eliminate General Exhaust in lab spaces and use VAV for both SA and Hood Exhaust. Annually, decommission, clearly label and close exhaust damper on lab hoods not in use. Purchase only high efficient ULT freezers and arrange equipment rooms similar to modern data center designs (pull heat away from the machines). Purchase research equipment that is also best in class for energy efficiency. General lighting at no more than 50 foot candles. Use task lighting as needed to meet 70 FC. Decouple ventilation from heating and cooling systems. Design lab space plug loads for average of 0.5-‐1.0 W/SF and lighting loads for 0.5 W/SF. Employ Dedicated OA Systems and Chilled beam techniques to minimize wasted energy. Electrical Closets, machine and mechanical rooms: Do not use heating units or air conditioning units (except in lab equipment spaces when recovering and reusing the BTUs). Use thermostatically controlled fans or dampers to remove the heat to an exhaust system where it can be recaptured and reused as needed. Alarm spaces for temperatures above 95F and below 40F as appropriate. Tel/Data Closets: Understand the expected heat output. Do not use air conditioning units for rooms with only routers, switches and terminal blocks. Use open plenum or thermostatically controlled exhaust fans to remove heat as needed. These rooms should be designed to operate below 85F and can use adjacent space air as make-‐up to their exhaust fan. Mobile Equipment: Purchase the most energy efficient options available. Use lowest emissions vehicles. Use most sustainable or renewable fuel type. Trash, Recycling and Compost: Ensure there are accommodations for trash, recycling and compostable bins anywhere waste is generated. Work with Operations to ensure areas will accommodate bin size and type changes in the future. Ensure primary compost collection in restrooms and areas where food is prepped, served or consumed. Require hauler to share weight data separately for trash, recycling and compost.
Renewable Energy Solar PV: PPA model, but ensure space is preserved on roof for future system. Systems can be placed on roofs, ground, parking canopies and parking garage roofs. Solar Thermal: PPA model. Ensure optimal roof space is preserved for future system. Size to preheat the chosen building system’s lowest thermal load. Solar Thermal Hybrid: PPA model, but ensure space is preserved on roof for future system. Size to preheat and pre-‐cool the chosen system’s lowest thermal load. 15
JHU High Performance Building Standards
Urban Wind: For new construction evaluate roof mount options. Preserve ideal roof space for future installations. Bio Fuels: When possible, consider alternatives to fossil fuels for vehicles and equipment.
References International Green Construction Code, 2012: http://publicecodes.cyberregs.com/icod/igcc/2012/index.htm?bu=IC-‐P-‐2012-‐000023&bu2=IC-‐P-‐2012-‐ 000019 ANSI/ASHRAE/IES Standard 90.1, 2013: https://www.ashrae.org/resources-‐-‐publications/bookstore/standard-‐90-‐1 International Energy Construction Code, 2012: http://publicecodes.cyberregs.com/icod/iecc/2012/ ANSI/ASHRAE/USGBC/IES 189.1 2014: http://publicecodes.cyberregs.com/icod/igcc/2012/icod_igcc_2012_ashrae189p1-‐2011_par001.htm
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