El Moore Greens Near Zero Energy Design
This is the work space for a design and learning community in Detroit that is developing a sustainable energy design for the El Moore building at 624 W. Alexandrine.
Contents
- 1 Near Zero Energy - Sustainable Design Schedule
- 2 Week 1 - Setting the Design Foundation
- 3 Week 2 - Field Trip
- 4 Week 3 - Building Envelope I
- 5 Week 4 - Building Envelope II
- 6 Week 5 - Windows and Doors
- 6.1 Windows
- 6.1.1 Window 101
- 6.1.2 Window Sustainability Goals
- 6.1.3 Window-to-Wall Ratio (WWR)
- 6.1.4 U Value (1/R)
- 6.1.5 Solar Heat Gain (SHGC)
- 6.1.6 Visible Light Transmittance (VT)
- 6.1.7 Air Infiltration
- 6.1.8 Historic acceptability
- 6.1.9 Natural Ventilation
- 6.1.10 Materials
- 6.1.11 Maintainability
- 6.1.12 Security
- 6.2 Doors
- 6.1 Windows
- 7 Week 6 - Thermal Modeling
- 8 Week 7 Geothermal
- 9 Week 8 - Solar Thermal Panels
- 10 Week 9A - Solar Site Survey and Strategies
- 11 Week 9B - Solar PV Panels
- 12 Week 10 - Ventilation
- 12.1 What is Ventilation in a Building?
- 12.2 What are the Requirements for Ventilation in the El Moore?
- 12.3 What is our Overall Strategy for Ventilation in the El Moore?
- 12.4 Detail Strategies: Mechanical Ventilation
- 12.5 ERV Suppliers
- 12.6 Detail Strategies: Natural Ventilation
- 12.7 Domestic Hot Water
- 13 Week 11 - Lighting and Appliances
Near Zero Energy - Sustainable Design Schedule
- Week 1 - Setting the Design Foundation
- Week 2 - Field Trip
- Week 3 - Envelope I
- Week 4 - Envelope II
- Week 5 - Windows and Doors
- Week 6 - Thermal Modeling
- Week 7 - Geothermal
- Week 8 - Solar - Thermal
- Week 9 - Solar - PV
- Week 10 - Natural Ventilation
- Week 11 - Lighting & Appliances
- Week 12 - Energy Controls and Accountability
Week 1 - Setting the Design Foundation
Sustainability Goals
El Moore Energy Sustainability Goals
- Sustain an indoor environment of human health and comfort by:
- Winter indoor temp 69F, Summer indoor Temp 76F
- Indoor humidity: 30% - 55%
- Maximize natural ventilation and lighting
- < 20% of Standard Energy Usage of a Building with Similar Use
- > 33% of Energy from renewable sources
- Clear Accountability ===> Basis for continuous improvement
Michigan Uniform Energy Code
Sustainable Energy Strategy
Step #1 - Size/Prioritize Demand
Step #2 - Reduce Demand w/ Passive Design
- Reduce demand by passive means by 70%
- Working with natural systems
- Use Passive Haus Institute's design principles
Step #3 - Meet Demand with No/Low Carbon, Renewable Sources
- Use no/low carbon, renewable sources to meet remaining demand
- Solar Hot Water
- Solar PV
- Geothermal - Earth's energy
- Natural Ventilation
- Manage system complexity / maintainability
Step #4 - Meet Demand with High Efficiency / Low Load Sources
- Use off-peak energy. Avoid adding to building new carbon based capacity (e.g. power plants)
- Use high efficiency...no need to use extreme efficiency since demand is down...very small yields.
Step #5 - Control and Accountability
- Direct feedback loop...you use the energy...you see the usage and pay for the energy.
Understanding Energy Demands
Typical Energy Demand Profiles
Heating
- Heating Season: mid-September - mid-May (8 months)
- Peak Season: mid-December - mid-February (2 months)
- Largest total demand in year
Cooling
- Cooling Season: mid-May - mid-September (4 months)
- Peak Season: July - August (2 months)
- Humidity is as important as temperature ... drive you to psycho...charts
- Solar gain is major contributor
- Typically drive peak hour sizing of equipment
Shoulder Seasons
- Spring Season: May - mid-June (1.5 months)
- Fall Season: September - mid-October (1.5 months)
- Varies widely...unpredictable
- Creates very difficult demand patterns
Domestic Hot Water
- Uses
- Shower (gal/min*min/day*persons)
- Washer (gal/load*loads/day*persons)
- Sinks (gal/min*min/day*persons)
- Dishwasher (gal/load*loads/day*persons)
- Demand Characteristics
- Peak Load
- City Water Temps (40F Winter? / 55F Summer)
Lighting
- Interior
- Motion detection
- Number, lumens and efficiency
- Exterior
- Photocell
- Number, lumens and efficiency
Appliances
- Refrigerator
- Dryer
- Washer
- Dishwasher
Natural Elements
- Where in the world is the El Moore
- 42 degrees north latitude
- Great lakes basin...clouds...temps
- Sun
- 23 East of South ...due to Woodward
- Solar south vs. magnetic South
- Sun rise, sun sets, height changes through out the year.
- Shading of trees, other buildings
- Same amount of sun as Florida! So what, Florida is not so good!
- Wind
- Urban micro wind climates
- Use for natural ventilation
- Earth
- Temperature
- Varies with depth
- Temperature
- Water
- Flows down hill...repeat...flows down hill
- Water is heavy...
- Average rain in Michigan
El Moore Building
Existing
- Built in 1898
- 4 floors w/ basement
- 15,000sf existing
- Size
- Width:
- Length:
- Height:
- Volume:
- Structure:
- Exterior Walls: brick and Lake Superior red sandstone
- Balloon frame
- Orientation: SE
- Window/Wall Ratio:
Plans
- Additions
- Add Elevator Tower
- Rooftop Cabins (4)
Thermal Physics
- Thermal Energy Movement
- Thermal energy movesfrom Hot -> to -> Cold
- Heat is transferred three ways
- Conduction (R Value)
- Convection
- Radiation
- Sensible and Latent Heat
- Building Performance
- R Value => Resistance to Conduction (e.g. Insulation)
- Air Infiltration => Air Exchanges per hour
- Blower door test
- U Value = Inverse of R (i.e 1/R)...used for windows
- Thermal Bridging
- Low thermal resistant penetrations in high thermally resistant structures (e.g. walls, roofs, etc)
- Happens often with:
- Joists
- Windows connections
- Doors connections
Human Comfort and Health
Human Comfort
Flickr Error ( Photo not found ): PhotoID 3614064282
- Human Comfort Zone describe elements of indoor human comfort
Human Health
- Air quality
- Toxicity of materials
Week 2 - Field Trip
- Visited the El Moore Building Site
Week 3 - Building Envelope I
Thermal Conduction 101
- Thermal Conduction Equation: heat transfer ...
- Increases with Delta T (difference in outdoor and indoor temperatures)
- Increases with Area
- Decreases with higher material resistance
- Decreases with thickness of envelop material
R values for Building Materials
- R Values for common Materials can be found in R Value Table on Wikipedia or here at the Colorado Energy website.
Envelope R Design
Sustainability R Goals
R Goals
- Walls = 25 R
- Ceiling = 60 R
- Basement Floor = 20 R
Limitations
- Thicker walls makes the units smaller, they are already challenged with a narrow width, and trying to accommodate the historic windows gets more difficult with longer extension jambs.
El Moore Envelope R Design
Energy Efficient Wall Framing
- Energy Efficient Wall Framing (DOE) handy reference from DOE on framing to reduce thermal bridging across studs.
Wall Systems
- Typical Historic Wall (w/o stud)
- Outdoor Air Film = .17 R
- 13" Brick (@.20 R/in) = 2.6 R
- 1" Air (@ 1.0 R / in) = 1.0 R
- 2" Polyiso (@ 5.0 R/in) = 10.0 R
- 3.5" Cellulose (@ 3.5 R/in)= 12.3 R
- 5/8" Drywall (@ 1.0 R/in) = 0.6 R
- Indoor Air Film = .68 R
- TOTAL WALL R VALUE = 27.35 R (Michigan Code requires 18 - 20R excluding air films)
- Typical Historic Wall (w/ stud)
- Outdoor Air Film = .17 R
- 13" Brick (@.20 R/in) = 2.6 R
- 1" Air (@ 1.0 R / in) = 1.0 R
- 2" Polyiso (@ 5.0 R/in) = 10.0 R
- 3.5" Wood Stud (@ 1.25 R/in)= 4.38 R
- 5/8" Drywall (@ 1.0 R/in) = 0.6 R
- Indoor Air Film = .68 R
- TOTAL WALL R VALUE = 19.43 R
- Typical Historic Wall (Assembly)
- TOTAL WALL R VALUE = 26.6 R
- Energy Star recommendation = 20.6 R (see Energy Star website page)
- 30% more than Energy Star
Ceiling Systems
- Typical Historic Ceiling (w/o joist)
- Outdoor Air Film = .17 R
- 2" Roofing (@.20 R/in) = 0.4 R
- 1" Air (@ 1.0 R / in) = 1.0 R
- 18" Cellulose (@ 3.5 R/in)= 63.0 R
- 2" Polyiso (@ 5.0 R/in) = 10.0 R
- 5/8" Drywall (@ 1.0 R/in) = 0.6 R
- Indoor Air Film = .61 R
- TOTAL CEILING R VALUE = 75.78 R ...(Michigan Code requires 38R excluding air films)
- Typical Historic Ceiling (w/ joist)
- Outdoor Air Film = .17 R
- 2" Roofing (@.20 R/in) = 2.6 R
- 1" Air (@ 1.0 R / in) = 1.0 R
- 12.5" Cellulose (@ 3.5 R/in)= 43.8 R
- 5.5" Wood Stud (@ 1.25 R/in)= 6.9 R
- 2" Polyiso (@ 5.0 R/in) = 10.0 R
- 5/8" Drywall (@ 1.0 R/in) = 0.6 R
- Indoor Air Film = .61 R
- TOTAL CEILING R VALUE = 65.68 R
- Typical Historic Ceiling (Assembly)
- TOTAL CEILING R VALUE = 74.8 R
- Energy Star recommendation = 52.0 R (see Energy Star website page)
- 43% better than Energy Star
World Wide Envelope (WWE) Smackdown I
Wall / Ceiling Section
- File:4th floor attic and masonry walls.pdf
- Exercises
- Exercise #1 - Calculate R Value of Wall (w/o Stud)
- Exercise #2 - Calculate R Value of Wall (w Stud)
- Exercise #3 - Calculate R Value of Ceiling (w/o Joist)
- Exercise #4 - Calculate R Value of Ceiling (w Joist)
WUFI Thermal Simulation Model
- Simulation #1 - New Wall System
- Simulation #2 - Existing Wall System
Week 4 - Building Envelope II
Infiltration
- Infiltration is the uncontrolled, unintentional introduction of outside air into the building [1] on Wikipedia.
- Measured in CFM and/or ACH
- ACH=(CFM x 60)/building volume in cubic feet
- Wind, buoyancy and building pressure effect
- Also brings in dust, drafts, moisture, and associated energy use
- Exfiltration is when air leaves the building, intentionally or not
- Ventilation means providing fresh clean air for occupants to breathe
- If the building is very well-sealed, may need to bring in outside air by mechanical means
- Measured in CFM and/or ACH
Building pressure
- Maintaining the building interior at a slight positive pressure helps reduce infiltration
- Imagine the building as a balloon, or a lung
Air sealing the building
- Windows and doors (more next week)
- Other penetrations
- Masonry
- Rigid insulation
- CSU article on air sealing homes [2]
- Blower Door Test
- Blower Door Directed Air Sealing
El Moore Air Infiltration Design
Air Infiltration Goal
- 0.50 ACH is the goal of the El Moore thermal design
Air Infiltration Design Strategies
- Windows
- Use Green Garage detail window opening sealing methods...foam all window frame to wall connections (see below).
- Use windows that have a low ACH...Kelly windows have a double seals
- Doors
- Use high performance weather stripping on all exterior doors
- Walls
- Foam seal all of the rigid polyiso panel seams
- Ceiling
- Foam seal all of the rigid polyiso panel seams
- Attach the wall polyiso to the ceiling polyiso with foam.
- Complex areas (e.g. when structural members come through the walls)
- Spray foam (not on brick per Historic req'ts)
Week 5 - Windows and Doors
Windows
Window 101
- Some great resources to start your learning about windows:
- National Fenestration Rating Council ... great basic data site...including understanding how windows are rated.
- Energy Star for Windows and Doors
Window Sustainability Goals
Flickr Error ( Photo not found ): PhotoID 3065347095 Our sustainability goals for the windows at the El Moore are:
- 1) Window-to-Wall Ratio (WWR) < 27%...studies show this is the maximum for an effective passive design.
- 2) U Value (1/R) < .30
- 3) Solar Heat Gain Coefficient (SHGC)... < .30 for all directions
- 4) Visual Light Transmittance (VLT or VT)... > .50
- 5) Air Infiltration ... window system < 0.20...window-to-wall connection < 0.10
- 6) Historic acceptability ... meet Department of Interior Standards
- 7) Natural Ventilation ... Ability to Open
- 8) Materials ... all recyclable, non-toxic, sustainably produced ... Cradle-to-Cradle
- 9) Maintainability ... ease to clean, durable, long life, can be repaired
- 10) Security ... discourage theft
Window-to-Wall Ratio (WWR)
- In general, best strategy is to reduce the Window to Wall Ratio (= Area of Window/Total Area of Wall)
- A 30R wall resists heat transfer 10X better than 3R (.33U) window.
- Studies of passive designs show that a maximum of 27% WWR
- The El Moore WWR is fixed for the historic building.
- El Moore WWR
- Historic (approx 19%)
- North: 24%
- South: 22%
- East: 17%
- West: 17%
- 5th Floor
- North: %
- South: %
- East: %
- West: %
- Tower
- North: %
- South: %
- East: %
- West: %
- Historic (approx 19%)
U Value (1/R)
- Measure of heat resistance of the window system ...this includes the glass, sash and frame.
- El Moore selection and rationale to meet U < .30 goal
- Cardinal 366 Glass - double pane...meets target U goal
- Kelly Window double hung wood frame window...wood has a lower U than aluminum
- 366 / Wood U Value = .28 (estimated)
- Resources
Solar Heat Gain (SHGC)
El Moore Selections to meet SHGC goals:
- Cardinal 366 glass on N/S/E/W windows
- 366 SHGC = .27
Visible Light Transmittance (VT)
VT Goals met through:
- Cardinal 366 glass on N/S/E/W windows
- 366 VT = 65
Air Infiltration
- Has two major parts:
- 1) Rated in the window system
- Kelly Window has a great double seal...our Green Garage windows went through blower test.
- 2) Related to where the window frame meets the wall system:
- Typically under the trim
- See Green Garage Wall-Window Detail
- Developed process for eliminating air infiltration using spray foam + infiltration (see image below)
- 1) Rated in the window system
Historic acceptability
- Need to meet the Department of Interior Standards for Windows (see p. 35)
- El Moore windows will match the current windows.
- Double pane window "darkness" has been approved by SHPO
Natural Ventilation
- Most current windows are double-hung...so bottom and top windows open.
- Design Guidelines:
- In = Out
- Enter low >>>>leave high
- Need to control with HVAC system ... especially humidity!
- Need to design:
- the "flow-thru" so air can enter and leave in equal volumes.
- Use double-hung window: open 4" at top and 4" at bottom
- Controls for announcing "natural ventilation day"
- Green Garage lesson = fewer natural ventilation days than thought
- Maybe 15 in spring and 15 in fall. Total = 30 / year.
- What about the elevator tower as a stack? Fire?
- the "flow-thru" so air can enter and leave in equal volumes.
Materials
- El Moore Selections:
- Aura Paint ... low VOC
- FSC Certified lumber or equivalent
- Reuse of wood for trim and jambs...via deconstruction
- Local Supplier: Kelly Window on Linwood; window glass made in Indiana
Maintainability
- Durability = Sustainability
- Wood Sealing + Painting
- Use Aura Paint...long lasting
- Factory sealer ((best)
- Seal on Double Pane
- Cardinal Metal seal is best in industry...lowest failure rate.
- Hinges and locks need to be heavy duty
- Wood Sealing + Painting
- Investigate "NEAT" coating on Cardinal glass .. sheds dirt...reduces cleaning
- Way to wash outside from inside??
Security
- Discourage entry
- Height is a barrier for most windows
- Windows have locks
- Garden windows may have some need
- indoor shutters (winter considerations)
Doors
Exterior Door Sustainability Goals
- U Value (1/R)of exterior doors
- Use wood (1.5R/in) or Fiberglass w/ insulated core (5R/in)
- Air Infiltration
- Try and achieve two point/strip wind barrier (one will leak) on all four sides
- You must have some way to create the compression to create the seal
- door closer
- threshold with gasket
- Carefully select weather stripping to meet your specific needs
- Great resource is PEMKO ... they make 1,000's of products to help you reduce drafts at doors
- Historic Acceptability
- Reuse historic doors
- have new doors made to matach historic pattern
- Natural Ventilation
- Can you keep the door open?
- Visible Light
- Include windows in doors where possible to bring in natural light
- Maintainability
- Fiberglass is the strongest (dent and rust resistant)
- Wood painted with Aura paint
- Materials
- Have doors custom made with reclaimed wood (Antil Windows)
- Reuse historic doors (we can reclaim 30 doors)for interior
- Security
- Need to design locking/access system for doors
- Fire Rating
- Hour rating
Week 6 - Thermal Modeling
Overview
- Purpose: estimate the thermal performence of a building
- Recent development ... last 15 years
- Supported by Dept of Energy...created DOE-2 Standard
- Many Whole Building Modeling tools approved by DOE
Thermal Modeling Goals
- Whole building / Holistic analysis
- Support "What If" Analysis
- One input for equipment sizing
eQuest Model
- Green Garage uses eQuest Whole Building Modeling tool
- DOE2 Approved Tool.. Dept of Energy Approved Modelling Standard
- Overview of functions and features
- We have experience with Energy 10 tool
Thermal Modeling Guide
- Inputs
- Output only as good as input (check and double check inputs)
- Envelope design
- Windows and doors
- Uses Michigan weather file (temp, humidity, precipitation, wind speed and direction, snow, sun/ radiant energy, cloud cover, ...etc.)
- Number of people that work in a building
- Outputs
- Typically look at peak cooling and heating loads
- Check and double check results
- More difficult to model the closer you get to Zero Energy
eQuest Updates: email from Kirsten (07/19/13)
Here's a couple of observations from the latest updates to the El Moore eQuest energy model:
Changing only the SHGC from .36 to .27 and U-value from 0.29 to 0.28 results in a change in whole-building space peak loads: Cooling from 115.0 to 105.8 KBTU/h, Heating from 179.0 to 176.9 KBTU/h
On top of that, I next changed the infiltration rate from 0.50 to 0.25 ACH with the following results: Cooling from 105.8 to 98.3 KBTU/h, Heating from 176.9 to 130.3 KBTU/h
So the SHGC made a relatively small difference but the infiltration rate made a more than 25% difference in heating load.
Week 7 Geothermal
Overview
- Uses the ground - air temperature differential to improve the efficiency of heating and cooling the building. The improvement in efficiency can be up to 30%.
- Ground temperature is between 40F (Winter) - 55F (Summer)
- In the summer the ground is cooler than the air, so is a better "source" for cooling
- Summer Example: Ground Temp = 55F vs. Ambient Air Temp = 90F
- In the winter the ground is warmer than the air and is a better source for heat
- Winter Example: Ground Temp = 40F vs. Ambient Air Temp = 10F
- In the summer the ground is cooler than the air, so is a better "source" for cooling
- Limitation is the ground absorbs energy slowly
Geothermal System Components
- Components
- Loop Field
- Types
- Horizontal
- Depth of loops > 8ft...typically 12ft.
- Vertical
- Depth of loops 150 - 200ft.
- Horizontal
- Sizing
- Rule of thumb 300ft of loop per 1 ton of energy
- Types
- Heat Pump
- Inverter compressor is preferred so it can match supply with demand more precisely (i.e. more efficient)
- Distribution / Exchangers
- Forced air
- Radiant floor
- Split System ... with refrigerant to the exchangers
- Loop Field
- Optional
- Domestic Hot Water can be connected for preheating hot water
El Moore Design Requirements
- El Moore Peak Loads
- Heating Peak Load = 130 KBTU/hr
- Cooling Peak Load = 98 KBTU/hr
- Domestic Hot Water needs to be estimated
El Moore Geothermal System Design
Potential Loop Field Design
- Field Size
- Rule of thumb: 1 ton = 300ft of loop
- El Moore Demand = 11 tons => 11 loops 300 ft long
- Location
- Back area
- Close to building if possible to reduce the supply lines
- Type
- Vertical Loops
- Potential Ideas
- Geothermal Sure Clip help to reduce length of boring by 30%. (Note: doesn't save on loop...may require more!)
- Potential Issues
- Limestone at 110ft found at Forest Arms
HVAC Equipment
- Mitsubishi City Multi
- City Multi unit (PDF Catalog)
- Water Source Heat Pump: Model pQRY-p120THMU-A (p. 76 in Catalog)
- Distribution Method: Ground Loop Water =to= Refrigerant
Domestic Hot Water
- Potential for integration with geothermal system with preheat tank
- excess heat in the summer could be returned through preheat tank
- use geothermal system to heat domestic hot water in the winter
Financial Incentives
- DTE Special Geothermal Rate
- includes time-of-day
- Federal Tax Incentives ... seed DSIRE website for Micigan
- 10% Federal tax credit for Commercial Buildings...In October 2008, the U.S. Congress passed The Emergency Economic Stabilization Act of 2008 (H.R. 1424), extending the Investment Tax Credit (ITC) to include geothermal heat pump systems. A 10% credit of the installed costs against a company's taxes is provided for a geothermal heat pump. Under U.S. Code Title 26, Section 48, 10% of the installed cost of a geothermal heat pump system (minus any subsidies) is applicable for corporate tax credits as ITC. There is no cap on the amount of qualifying expenditures that can be used for the credit, nor a limit on the credit itself. It's in effect through 2016.
- Accelerated depreciation
Week 8 - Solar Thermal Panels
Overview
Why is it Important?
A solar thermal panel subsystem is important to a building's sustainability because it:
- Directly connects the building and its occupants to the earth's natural energy source: the sun. The sun is the source of all our energy.
- It is a renewable source of energy with no carbon footprint, except for the small pump (which may be run using photovoltaic collectors).
- Reduces the operating costs of the building by supplying the energy to heat the building and provide hot water.
Solar Thermal Fun Facts...to know and tell
- raise the temperature of water using the sun's radiant energy.
- are typically 70 - 80% efficient in converting the sun's energy
- come in various sizes ... 28" x 50"... to 48" x 120"
- over 50 manufacturers...so many to choose from
- water flows through the panels at approximately 1 gpm.
- To Maximize output the panels should be:
- facing "solar" south...it's constant throughout the year
- tipped up from the horizontal at the same degrees as the latitude the panel is located (our is 42 degrees)
- Collector energy production (per [www.builditsolar.com/ Build it Solar]:
- Full Sun: 750 BTU/sf/day Winter
- Partly Sunny: 560 BTU/sf/day Winter
- Cloudy: 375 BTU/sf/day Winter
Types of Solar Thermal Panels
Two types of solar thermal panels
- Flat panel
- Very simple
- Very reliable
- Efficiencies up to 80%
- Evacuated tube
- Slightly more efficient...especially with sun at extreme angles
- Higher failure rates with leaks in tubes
Components of a solar thermal system
Panel (flat panel)
- Frame / box (metal)... structural and holds heat in
- Insulation ... keeps heat from being transfered to the frame
- Copper tubing and fins painted black ...absorbs the sun's energy and transfers to water in the tube
- Glass ... creates greenhouse effect between the glass and tube/fins
Structural
- Framing
- We've used Unistrut
- Fasteners for Panels
- Weights / Tie down ... offset high wind loads...must be calculated by licensed structural engineer/architect
Storage Tanks
- Store heat in water until it is needed
- handles time differential between when heat is generated and when it is needed
Other System Components
- Pumps ... to pump the liquid through the panels
- Temperature sensors ... to determine if the panels are hot enough to raise water temperature water
- Values ... open and close to allow water to flow on desired circuit
- Controls ... turn system on when opportunity to gain BTU's, turn off when no opportunity
System Types
- Drainback
- No additive to water...water stays clean
- Longer life of panels
- Risk of freezing if drainback system fails
- Closed Loop with Glycol (or equivalent)
- Additive to water...water destroyed...small amount
- Longer life of panels
- Risk of freezing if drainback system fails
Uses for the Hot Water
- preheating domestic hot water
- heating the building
Example: Green Garage Solar Thermal System
- Green Garage Solar thermal panels
- Green Garage Solar Thermal Energy Produced
- Note: 750 BTU/day * 40 sf/panel * 10 panels = 300,000 BTU
El Moore Solar Design Strategy
Sustainability Goals
- Maximize the renewable energy production in high potential solar areas
- Maintainable...repair panels, system
- Simplicity
- Fit Historic Requirements
Solar Energy is Best When
- Access to full sun ... year-round (no trees)
- Panels can be positioned to face "solar" south
- Production can overcome cost/complexity of infrastructure
- Significant demand for electricity and/or hot water
El Moore Solar Potential Assessment
- Access to full sun ... year-round (no trees, buildings)...Limited
- Panels can be positioned to face "solar" south... Very Limited
- Production can overcome cost/complexity of infrastructure... Possible...need to be very careful
- Significant demand for electricity and/or hot water... Yes!
El Moore High Potential Sites
- Rooftop cabins ... roof
- Area (sf)
- Plus
- Open exposure to sun
- Minus
- Difficult to face solar south
- Access could be tricky
- Historic visibility requirements
- Elevator Tower Roof
- Area (sf)
- Plus
- Open exposure to sun
- Can position to solar south
- Minus
- Limited Size
- Access could be tricky
- Historic visibility requirements
Week 9A - Solar Site Survey and Strategies
El Moore and the Sun
- El Moore Relationship to the Path of the Sun
- Ave Solar Radiation
- Sun Map from NOAA Shows the building's orientation to the sun.
- Alternative Sun Map SunCalc
- Google Sketchup Model of the El Moore
- El Moore Key Data Needed
- Roof Areas (sf)
- Cabin Roof Area Total = 1,500sf
- Front Cabins (700 sf)
- Rear Cabins (800 sf)
- Elevator Tower Roof
- Upper Roof =
- Lower Roof =
- Cabin Roof Area Total = 1,500sf
- Latitude and Longitude
- Lat = 42.3487N
- Lon = -83.0659
- Sun Obstructions
- Elevator Tower (+ 8-10ft above cabin roof)
- Roof Areas (sf)
How much energy from Sun?
- General Radiation Information
- "The solar irradiance intercepted by the earth at the top of the atmosphere, the solar constant, is quite stable with an observed value of 1365 Watts/m2 ± 0.3%. However, in the mean, only about half of this energy reaches the surface and is available to drive surface and biological processes. Of the other half, approximately 30% is reflected back to space, and the remaining 20% is absorbed by clouds, dust, and "greenhouse" gasses such as water vapor, carbon dioxide, and ozone." ... from NOAA
- Weather Underground Solar Energy Calculator
- Calculates kWh per month using weather data
How much energy (kW) from Solar Panel?
- Solar Panel Efficiency? Find it at SRoeCo Website ... Excellent discussion of panel efficiency and value.
- Weather Underground Solar Energy Calculator
- Number of panels
- Total Area 1,500sf
- Usable Area = 1,200ft (75% of total)
- Area of Panel = 10.3 sf
- Number of Panels = 116...use 110 panels
- Angle of the Panels
- Number of panels
- Sun Irradiance on Panel by Angle
- Current angle (front to back) = 10 degrees
- Possible angle (side-to-side) = 25 degrees
- Total Angle (diagonal) = 30 degrees-ish
What is the best Solar PV Panel for the El Moore?
- Need to look at value = Cost ($) / Output (PTC) (kW)
Week 9B - Solar PV Panels
Overview
Why is it Important?
Financial Incentives
- DTE Special Net Metering
- Federal Tax Incentives ... seed DSIRE website for Michigan
- 30% Federal tax credit for Commercial Buildings...In October 2008, the U.S. Congress passed The Emergency Economic Stabilization Act of 2008 (H.R. 1424), extending the Investment Tax Credit (ITC) to include solar panel system systems. A 10% credit of the installed costs against a company's taxes is provided for a geothermal heat pump. Under U.S. Code Title 26, Section 48, 30% of the installed cost of a solar panel system (minus any subsidies) is applicable for corporate tax credits as ITC. There is no cap on the amount of qualifying expenditures that can be used for the credit, nor a limit on the credit itself. It's in effect through 2016.
- Accelerated depreciation
Week 10 - Ventilation
What is Ventilation in a Building?
- It is the exchange of fresh air with "stale" air to maintain the air environment healthy
- Controls high, unhealthy levels of CO2
- Key component to human comfort
- Prevents "close" feeling
- Especially needed in tight buildings
- Two Methods for Ventilation are:
- Natural Ventilation ... importance
- Windows that open
- Mechanical Ventilation
- Natural Ventilation ... importance
What are the Requirements for Ventilation in the El Moore?
- We're not fully certain and need more research
- ASHRAE 62.2 says 0.35 ACH min...need to figure out how to apply with 0.25 ACH + bathroom requirements
- File:Image-ASHRAE 62-2001 Ventilation Standard.pdf .. the latest I could find.
- Also there is a spreadsheet to help calculate ventilation requirements...oh boy. 62n-VRP.xls...but no multi-family.
- Mechanical Ventilation Requirements have two main components:
- Makeup Air (outdoor air)
- Exhaust (e.g. bathrooms)
- Exhaust Ventilation. Exhaust airflow shall be provided in accordance with the requirements in Table 6.4.
- Exhaust makeup air may be any combination of outdoor air, recirculated air, and transfer air.
- Possible Calculation of Ventilation Requirement
- Version 1.0: Currently using:
- 50cfm for bathrooms
- 50 cfm for elevator tower
* Version 2.0: Estimate
- 2nd Floor 2Bd
- Bathroom 25cfm ... continuous
- Kitchen 25cfm ... continuous
- Living areas = 3 persons x 15 cfm = 45 cfm
- 3 Persons = Bedroom #1 @ 2 persons + Bedroom #2 @ 1 person
- Total 95 cfm = 25cfm + 25cfm + 45cfm
- Air Source: 95 cfm = 45cfm fresh Outdoor Air + 50 cfm Recirculated
- 2nd Floor 1Bd
- Bathroom 25cfm ... continuous
- Kitchen 25cfm ... continuous
- Living areas = 2 persons x 15 cfm = 30 cfm
- 2 Persons = Bedroom #1 @ 2 persons
- Total 90 cfm = 25cfm + 35cfm + 30cfm
- Air Source: 80 cfm = 30cfm fresh Outdoor Air + 50 cfm Recirculated
- 2nd Floor 2Bd
What is our Overall Strategy for Ventilation in the El Moore?
Mechanical Ventilation
- Use Energy Recovery Ventilator (ERV) to supply the fresh air
- Energy Recovery Ventilators exchange heat and humidity
- Can we tie the supply into the Mitsubishi Ceiling Units?
Natural Ventilation
- Use the single hung windows
- Can't achieve cross flows which will reduce the capacity by 50%
- Can't depend on this to meet requirements...but can help at the margin
Detail Strategies: Mechanical Ventilation
Energy Recovery Ventilator (ERV)
How does it Work?
- Transfers heat and humidity from the
What are the Benefits?
- ERV can transfer 70 - 80% of the energy in the indoor air going out to the outdoor air coming in.
- Varies by delta T
What is the ERV Design?
- Use three ERV's (800cfm each)
- #1 ERV handles Basement and 1st Floor ... located in Basement
- #2 ERV handles 2nd and 3rd Floor ... located in stairwell ... 2.5 level
- #3 ERV handles 4th and 5th Floor ... located in stairwell ... 4.75 level
- Controls
- ERV is running constantly (7/24/265)
Ventilation Distribution Design (ERV)
ERV Suppliers
Detail Strategies: Natural Ventilation
Windows
- Use single hung windows
- Explore value of double hung windows
- Not worth the added air infiltration in the upper window if double hung
- Explore value of double hung windows
Domestic Hot Water
What does this include?
- Tub/Showers
- Bathroom Faucets
- Kitchen Faucets
- Laundry Washers
- Replace soap with ionizer
How much Hot Water (BTU) will El Moore Use?
- Short stay
- Long stay
Residential Hot Water 101
- The #3 most important segment of energy use
- Tank temperature = 130F
- Ground water temp
- Summer = 55F
- Winter = 40F
- Rated on flow x temperature rise = heated volume
- BTU levels
- Raise 1 lb of water 1F
- 1 gallon = 8.3 lbs @ +1 F = 8.3 BTU
- Tends to peak slightly in the summer
Strategy
- Three stage
- #1 Waste heat recovery -> Preheat tank (up to 115F)
- #2 Geothermal -> preheat (up to 115F)
- #3 Tankless (gas) on each floor to reduce the heat loss in pipes (e.g. running the water to get it hot)
Equipment
- Mitsubishi PWFY Hydronic Heat Exchanger
- Can the heat recovery unit heat this during heating season?