Week 2 HVAC systems at Y2E2
Today s lecture will focus on HVAC systems and the type of systems contained in Y2E2 Basic info about Y2E2 Contains a diverse range of HVAC Systems and zone equipment Introduce the data collection system and how to access that data Introduce Product Hierarchies to begin data analysis 2
This class focuses on the analytical process to understand actual building performance HVAC Systems at Y2E2
Y2E2 design intent: maintain thermal comfort in spaces by using the minimal amount of energy 4
HVAC systems must account for a variety of interrelated factors and ensure building function Room Building geometry Constructions and Materials Internal loads People Lights Equipment Solar gains Air infiltration HVAC system System type Equipment parameters Operating schedules Controls Weather 5
Y2E2 is a new, large multi-purpose building 4 stories with approx 160,000 sf A diverse range of space types ensures a worthy challenge for analysis 6
Low energy features to mitigate peak load & reduce overall energy consumption Atria provide daylighting, support natural ventilation Manually and automatically operable windows support natural ventilation 7
Exposed concrete floors increase building thermal mass 8
Active beams provide efficient conditioned fresh air to spaces: mostly passive 9
Small PV units on roof contribute 1-2% of total building electricity PV Arrays 10
District heating and cooling supplies most of the hot and chilled water required on campus Cardinal cogeneration plant http://news.stanford.edu/news/2009/october19/stanford-carbon-footprint-101909.html 11
HVAC Systems
Stanford CoGen Plant HVAC Systems at Y2E2 supplies chilled water directly, steam to tempered water heat exchanger for heating Cold water loop Secondary loop AHU Coils Fan coil: coils CAV/VAV box: coils Active beams (cooling) Heat Exchanger Hot water loop Secondary loop AHU Coils Baseboard radiators CAV box: coils Active beams Radiant slab VAVs (heating) 13
Main chilled water loop serves cooling coils and server rack and tempered water loop Serves: Tempered water loop Cooling coils (AHU, FC, CVs, VAVs) Server Rack 14
Main chilled water loop Serves: Tempered water loop Cooling coils (AHU, FC, CVs, VAVs) Server Rack 15
The tempered chilled water loop serves active beams Serves: Active beams 16
Tempered chilled water loop Serves: Active beams 17
The main hot water loop serves heating coils, radiators and tempered water loop Serves: Tempered water loop Heating coils (AHU, CVs) Radiators 18
Main hot water loop Serves: Tempered water loop Heating coils (AHU, CVs) Radiators 19
Tempered hot water loop serves active beams radiant slab, heating coils (VAVs) Serves: Active beams Radiant slab Heating coils (VAVs) 20
Tempered hot water loop Serves: Active beams Radiant slab Heating coils (VAVs) 21
Zoning Example: 2 nd Floor
Integrated HVAC air systems serve offices and exhaust through an atrium Outside Air AHU CAV or VAV box CAV or VAV box Atrium Active beam (cooling/ heating) Active beam (cooling/ heating) Diffuser Active beam and/or diffuser Zone 1 Zone 2 Zone 3 Zone 23
North facing space contain radiators to balance out fabric losses Fabric heat loss through materials w/ temperature difference, e.g., walls, windows, floor, roof. 24
A typical air handling unit contains fans, coils and HR HR = heat recovery subsystem 25
Air handling unit 26
Fan coil units condition mechanical, electrical and data rooms 27
Active beams provide supplementary heating or cooling 28
Two representative offices on the north side contain measurement points for radiant heating and ceiling 29
Two representative offices on the south/west side contain measurement points for active beams Active beams for heating and cooling 30
The overall mechanical ventilation strategy uses atria for to exhaust air 31
Naturally ventilated perimeter zones exhaust to the atria, air flow rates are controlled by dampers 32
The control system enables building and campus wide access to data LONWORKS based control system ilon servers as interface between LON and Ethernet Tobias data logger Saved at one minute interval into MySQL database Data access via MySQL client IP: 171.67.81.12 Username: CEE243 Password: Iwantmoredata More info in tutorial 33
Product Hierarchies (original) enable a view of buildings for the purpose of performance analysis Portfolio Site Building Building Story Tennant Zone/Micro Zone HVAC Systems System Components Zone/Micro Zone Legend: Physical asset System or component HVAC Systems Has Part 34
Product Hierarchies (Maile 2010) link geometric and HVAC representations of building objects 35
Product Hierarchies have multiple uses including displaying efficacy of measurement points 36
Product Hierarchies: Y2E2 37
Concluding 38
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