Building Environmental Systems Objectives: What are BES? What do Architectural Engineers do with BES? What BES courses will you have to take? What additional options are there? Why is knowledge of BES useful to an architectural engineer?
What are BES? Mechanical Electrical Lighting Plumbing Heating, ventilation, air conditioning (HVAC) Electrical Power generation Distribution Lighting Plumbing Specialty and communication Acoustics and noise control Transport
Where are BES? 3D model – Biomedical Engineering (BME) Building 3
3D model – Biomedical Engineering (BME) Building 4
Structural vs. Environmental Systems in Buildings 5
Space for Environmental Systems Mechanical rooms (floors) Rooftop units for smaller buildings
Space for Environmental Systems Ref: Tao and Janis (2001)
Cost of Environmental Systems More expensive then Ref: Tao and Janis (2001)
Total Energy Consumption by Source and Sector in U.S. (2007) Total primary energy: 101.4 x 1015 Btu ( 29,700,000 thousand MWh) ~ 21% residential ~ 18% commercial
Building Energy Use and Green House Emission ~36% 17.5% 18.6% 35.8% 28.1% http://www.eia.doe.gov/oiaf/1605/ggrpt/index.html http://www.eia.doe.gov/oiaf/1605/ggrpt/flowchart.html
What Building System is Responsible for Most Energy Use in this Building? Lighting HVAC Water Heating Computers and other appliances Refrigeration
Energy Consumption in Commercial Buildings Cooking Cooling Heating Lighting Office Equipment Other Refrigeration Ventilation Water Heating HVAC is largest component of energy use Lighting is second Lighting might be smaller portion – including cooling to make up for heat of lighting Energy isn’t only criteria, Source: DOE
HVAC - 45% Source: DOE HVAC is largest component of energy use Lighting is second Lighting might be smaller portion – including cooling to make up for heat of lighting Energy isn’t only criteria, Source: DOE
Energy Consumption Monthly Profile for 100,000 sf ECJ Building, UT at Austin ~12% ~96 MWh
Same Building in Minneapolis, Minnesota ~150% ~845 MWh NOTE: We would never build the same buildings in Austin and Minneapolis
Energy Bill for Residential Buildings http://www.energystar.gov
Analysis of Energy Consumption in Residential Buildings We are considering a model building used in Austin Energy analyses Model house: - Location in Austin 2300sf R13 walls R30 attic 4 occupants Surface absorptivity to Solar rad.: 0.7 Typical (average) internal loads Infiltration/Ventilation 0.5 ACH - Double glazed widows Glazing are 20% south, 25 north, 5% east and west - SHGC=0.54 (reflective – bronze - glass)
Where the Energy Goes? 30% cooling, 14% heating, 12% hot water, 44% light and appliances, and other internal electric devices Energy for heating and cooling (44%): contribution of internal heating loads: 2.3% contribution of all solar radiation through winnow: ~19% contribution of infiltration: 5.5% contribution of conduction through roof, walls, floor ~17% For different climate condition, or different house, or non-typical users these numbers will be different ! For other climate conditions, we would build this house differently
Target value for a new house in Austin New single family 2262 sf, 2-story home (Austin Energy Data)
HVAC systems
HVAC Largest share of energy use in buildings Substantial impact on indoor air quality (IAQ) What do Architectural Engineers do? Size conditioning and distribution systems Calculate heating and cooling loads Select materials Troubleshoot problems, building forensics Integrate HVAC into buildings Improve indoor air quality
Electrical Systems Photovoltaic systems
Electrical Systems System design Emergency power Alternative power sources Specialty systems What do Architectural Engineers do? Size system Design specialty systems Integrate with other systems
Lighting in buildings Restaurant with $70 meal Light affect: Productivity Comfort/emotion Safety Sale …. Restaurant with $7 meal
Lighting Significant energy use Occupant comfort, productivity, safety, health(?) Interaction with HVAC What do Architectural Engineers do? Design lighting levels Select type of bulbs and fixtures Integrate into building (daylighting)
Day lighting and artificial lighting What is the difference between this two pictures?
Building systems affect the costs First cost vs. Operating cost Size of equipment Design parameters Operating cost Built-in equipment Operational parameters Energy analyses for optimum balance
What is Building Energy Analysis ? Design iterations to optimize shape and energy use Solutions: passive shadings positions and area of windows insulation value tightly sealed envelope high-performance window position of solar collectors Architectural models Energy-simulation models Design iterations
You will take at least 2 Courses: 1) 346N: Building Environmental Systems prerequisites: thermodynamics, physics 2) ARE 346P: HVAC Design or 2) ARE 377K: Design of Energy Efficient and Healthy Buildings What else can you take? Renewable Energy and Environmental Sustainability Energy Simulation for Building Design Advanced Energy Efficient and Healthy Buildings Building Energy Management Systems Indoor Air Quality (three courses) Outside of our department Fire safety Lighting, etc.
Why Should You Care about building environmental systems? Many jobs in HVAC systems http://eeace.com/ , http://www.shahsmith.com/page.cfm?page=home , http://www.tgce.com/ Focus on building durability, energy use, indoor air quality. Companies are hiring people that can work in teams. You will have to evaluate BES claims.
Students Interested in Sustainable Design LEED - Leadership in Energy and Environmental Design http://www.usgbc.org/DisplayPage.aspx?CMSPageID=1989 1) LEED Certification require that building has analysis related to energy performance and indoor air quality 2) All government buildings require energy analysis
Your Questions
Project 2x4 vs 2x6 framing ~ Difference is only in exterior studs R13 R - Resistance Conversion
Heat loses and gains through walls Q = A ∙U ∙ ∆T U=1/Rwall assembly A - Area of the walls ∆T = Tinside – Toutside Set point Change from hour to hour
Wall assembly Rwall assembly= Reach_component_of_the_assembly
Example: