hancock academy 1 energy modeling for different housing types
TRANSCRIPT
Automate Energy Efficiency Projects
Hancock Academy Session 1
Danielle Amasia [email protected]
HEAT Energy Modeling for Different Housing TypesArt Willcox
[email protected] Reminder: BPI requires you to enter a BPI number, email me or [email protected] if you forgot to enter a BPI no. when registering
Agenda
Energy modeling with HEAT — Single Family
Energy modeling with HEAT — Manufactured Home
Energy Modeling with HEAT
Launch
Different Housing Types
680 square feet
Floor Plan
10 x 20
30 x 16
Methodology Review• HEAT doesn’t use billing data to determine energy consumption.
Instead, it uses the user-entered data inputs of existing conditions and determining the heat loss for the heating season and the heat gain for the cooling season.
• HEAT calculates this consumption load by building component (aka energy audit section) and uses bin analysis methodology from ASHRAE
Example Bin Data• TMY 3 Weather Data
City Direction deg-30 deg-25 deg-20 deg-15 deg-10 deg-5 deg0 deg5 deg10 deg15 deg20 deg25 deg30 deg35 deg40 deg45 deg50 deg55 deg60 deg65 deg70 deg75 deg80 deg85 deg90 deg95 deg100 deg105 deg110 deg115
PATUXENT RIVER NAS North 0 0 0 0 0 0 0 0 0 4 28 33 91 404 735 721 602 851 841 1024 774 894 876 630 195 57 0 0 0 0
SALISBURY WICOMICO CO AP North 0 0 0 0 0 0 0 0 0 13 53 156 280 475 563 736 503 893 869 957 883 689 738 525 313 89 25 0 0 0
BALTIMORE BLT-WASHNGTN INT'L North 0 0 0 0 0 0 0 0 19 68 136 214 336 540 756 632 583 813 721 903 762 753 695 492 239 94 4 0 0 0
HAGERSTOWN RGNL RIC North 0 0 0 0 0 0 0 0 19 85 202 243 326 632 753 640 568 740 702 886 897 778 596 457 164 51 18 3 0 0
ANDREWS AFB North 0 0 0 0 0 0 1 4 9 71 178 277 283 476 651 858 551 795 768 782 873 819 649 420 192 72 28 3 0 0
Baltimore North 0 0 0 0 0 0 0 0 19 68 136 214 336 540 756 632 708 688 721 903 762 753 695 492 239 98 0 0 0 0
Step 1: Schedule the Audit in WAP Online
Step 2: Energy Audit Steps — BPI Guided Audit
Building Information 1. Weather data 2. House dimensions ( For example, if a house had a basement the entry would be
44x24x8 = floor 1 , then a new row with 44x24x8= floor 2) 3. Optional = Building information / general information
Heating/ Cooling 1. Add existing heating system (required fields = system type, usage ratio = 100%) 2. Add existing cooling system (+ sign on the bottom right adds new systems, usage
ratio, system age are required)
Zonal Distribution Quantity - total linear ft of supply duct, greater than 90 % of the duct work is within the thermal envelope, no observable leaks and there is less than R4 existing
Lighting 1. Choose "Whole-House Lighting" 2. Choose the existing fixture (ex: Incandescent 50 watt) 3. The rest of the screen populates for you
Hot water heater direct install 1. Choose a measure, like a shower head and enter quantity and price 2. "Choose this row to add a new entry" to add the aerators (or next measure)
Hot water tank Size, Temperature, Usage ratio and pipe length
Wall Example of 2 wall entries, one for the north and south, one for the east and west:
1.Length x width , quantity of walls defined (2), orientation (east), exsiting R value of wall 2.Length x width , quantity of walls defined (2), orientation (west), exsiting R value of wall
(On each wall, click "window and doors" and create a window type and place the windows on the wall)
Basement Basement floor: 1.The length and width of the floor below (section type = cantilever floor, framing hardwood floor) 2. Second entry - Conditioned walls The perimeter of the walls x the wall height (section type = conditioned, heated basement walls)
Air Infiltration If you choose the fan pressure and house pressure, the CFM will auto calculate. Then enter the target.
Click energy model to see the results, and modeling report to see an example homeowner report
Step 3: Review Energy Model Output
Questions
What if the home is attached to another home thus only allowing us to see 3 walls
If an auditor needs to have an attic hatch insulated and airsealed (1st energy saving measure) and also wanted to add insulation to the attic (2nd energy savings measure). How would the auditor be able to do two energy savings to the attic section?
More about the energy model
Heating and Cooling
The energy consumption of heating and cooling equipment is based on fuel type and steady-state efficiency. Heat pump consumption is based on HSPF and SEER values.
Central air-conditioners are described by SEER. Electric consumption of room air-conditioners are based on EER values and the percentage of square footage cooled by the equipment over the total square footage of the house
More about the energy model
Duct SystemsModel any type - Flex, Duct, Ductless, etc.
• Duct losses are also taken into consideration in calculating energy consumption of heating and cooling equipment. The efficiency of the duct system is based on the percentage of the duct system located within the conditioned envelope, the level of existing duct insulation, and a qualitative description of the duct leakage. These three metrics are used to determine a percent efficiency of the distribution system based on the BPI Distribution Efficiency Look-up Table. The improvement measure selected for the duct system determines the post-retrofit efficiency of the system and these two numbers are used to calculate savings from duct improvements.
More about the energy model
Air Infiltration
• Blower door readings are used to calculate heat loss or heat gain from infiltration
Complex BasementsConditioned, Unconditioned, Buffered Floors and
vented and unvented crawlspces
• Uses ground temperature data to calculate heat transfer through below grade foundation components. It also uses outside temperature and house temperature for the appropriate areas.
More about the energy model
Conditioned Basements - Treated like typical walls
• Conditioned Basements and Exposed Floors
• The above-grade components in a conditioned basement and exposed floors, including the above-grade wall and sill, are treated like typical walls with the inside temperature being 68F or 78F degrees and the outside temperature being the bin temperatures.
• For below-grade walls and slab floors of conditioned basements, the temperature of the space is 68F degrees and 78F degrees for the heating and cooling season, respectively.
More about the energy model
Unconditioned Basements
• For these foundation spaces, it is necessary to determine how the temperature is affected by the ground temperature, the ambient temperature, and the temperature in the house. For these foundation types where the temperature in the foundation is unknown, a multistep process is performed to determine this foundation temperature.
More about the energy modelThermal Boundaries
• When entering a foundation into HEAT, it is the responsibility of the auditor to determine whether the thermal boundary should be taken at the frame floor or at the foundation walls.
• If the auditor chooses to insulate the foundation walls and place the thermal boundary there, the initial thermal boundary is still taken to be the floor and the final thermal boundary is taken to be the walls, the sill, and the slab floor, if applicable.
• Therefore, the savings of insulating the foundation walls is calculated by subtracting the total heat loss across the now-insulated foundation from the initial heat loss across the floor.
More about the energy modelWindows and Solar Heat Gain
• For windows, in addition to a bin methodology UA calculation, solar heat gain is also taken into account.
• Average transmitted solar radiation data for unshaded surfaces of each orientation was taken from the National Renewable Energy Laboratory’s Solar Radiation Manual for Buildings: Blue Book.
• The auditor must assign each wall an orientation and each window entry to a wall for HEAT to determine the appropriate solar gain number to use.
More about the energy modelBaseload - Appliances, Hot Water, Renewables
• HEAT addresses refrigerator, lighting, and hot water measures. The electric consumption of existing refrigerators is determined by entering the kilowatt-hours metered and amount of time the refrigerator was metered. These are used to calculate average annual electricity consumption. Annual electricity savings is calculated by subtracting the listed kilowatt-hour usage of the replacement refrigerator from the calculated usage of the existing refrigerator.
• Lighting savings are calculated by entering in the wattage, hours operated, and quantity of the lights to be replaced and the replacement lights.
• Hot water consumption is based on hot water usage data by household size obtained from EIA 2005 Residential Energy Consumption Survey. Improvement measures for hot water consumption are assigned a fuel type and a percent efficiency savings number that is used to calculate fuel and dollar savings from these measures. Tank and pipe insulation are assigned 3% savings and 0.5% savings, respectively
The Energy Model Installs the Previous Measure
• To effectively interact measures, the Hancock software performs an iterative analysis based on savings-to-investment ratios (SIRs) rank of each measure.
The first step in the process is an initial calculation of existing building conditions. After initial heat loss and gain portions are determined, the software then determines individual energy savings for each auditor-selected measure. This is used to determine the individual SIRs and to rank the measures.
The Energy Model Installs the Previous Measure
• Once the highest SIR measure is determined, it is then “installed” by the software and considered to be the part of the starting condition for the next iteration. This process is repeated until all measures are installed by the program and a final ranked, interacted list of measures is generated. This method ensures that if a heating system improvement measure is found to be most cost-effective, the savings of any building envelope measure will be calculated using the increased heating system efficiency number. Likewise, if an insulation or air-sealing measure is found to be most cost-effective, the savings of any mechanical system measure will be calculated using a reduced heating and cooling load.
