New Homes EPS Modeling Frequently Asked Questions. Developed by Energy Trust of Oregon

Transcription

1 New Homes EPS Modeling Frequently Asked Questions Developed by Energy Trust of Oregon 1

2 General Questions 3 REM/Rate questions 4 -Creating custom entries 4 -Modeling Heat Pumps 5 -Modeling HRV/ERV 7 -Modeling adiabatic wall system 8 Required vs. Optional fields on the AXIS checklist 8 ADU requirements 8 AXIS help 9 2

3 General Questions 1) What version of REM/Rate should I be using for the New Homes program? As of January 1, 2015, the NH Program requires all models submitted for EPS to be modeling using REM/Rate v14.6 Northwest. 2) Do I need to use the Northwest version of REM/Rate for the NH Program? Yes, all verifiers/modelers must be using and submitting homes under the Northwest version of REM/Rate to receive EPS and incentives. Please contact your provider if you have questions on how to access the Northwest version of REM/Rate. 3) If I have modeling questions who should I contact? All modeling questions should be sent to NewHomesTechnical@CSGRP.com. 4) How do I submit projects for EPS and incentives? All projects must be submitted via the AXIS database to receive EPS and incentives. If you are not currently set up with an AXIS account please contact support@pivotalenergysolutions.com. 5) Is there a location/website that holds all the relevant documents for verifiers and modelers? Yes, the new homes verifier website is the place to go for all of your New Homes program documents, resources, marketing materials, events calendars and educational trainings and links. Please visit the website You must have a login and password to access this website. This information will be supplied to you once you sign up as a trade alley. Please do not share this login information outside of the verifier/modeler network. 6) What does my energy model compare to? The verified energy model in REM/Rate is compared to the User Defined Reference Home, UDRH, which is the same size home you modeled built to code specifications. The difference in energy consumption between modeled home and code home gives the program our energy savings. These savings are also used to determine the percentage improvement of the built home over the hypothetical code house. The percentage improvement is use to determine the incentive levels we provide. 3

4 REM/Rate Questions 1) What is my best resource for REM/Rate and modeling questions? The modeling reference guide, found on the verifier website ( should be your first resource when you have questions with REM/Rate and modeling for the NW program. If you still have questions after reading this document please contact Additionally, REM/Rate has a built in Help tool that can be used to learn more about specific items within REM/Rate. This information can be very helpful for general questions and additional information. 2) How do I load the Oregon library set and New Homes program specific User Defined Reference Home, UDRH? Please review the modeling reference guide which does a great job outlining the steps you will need to take to load the OR library set and UDRH. If you run into issues or continue to have questions on this process please contact NewHomesTechnical@csgrp.com. 3) How else can I troubleshoot REM/Rate questions? REM/Rate has a very handy Help button found on the top toolbar when using the modeling software. This button offers specific information for each page you are using in REM/Rate and does a great job at explaining what information should be capture on the page you are currently on. Please keep in mind that REM/Rate is used in many different programs across the nation and that not all the details within the REM/Rate Help tool apply to the Energy Trust program. If you find conflicting guidance within REM/Rate, the Energy Trust New Homes protocol and modeling reference guide should be used. 4) How do I create custom entries in REM/Rate? All modelers should be using the OR library set provided to them via the New Home s verifier website. REM/Rate does allow you to create a custom entry if you are not able to find the utility provider, assembly or mechanical equipment entry in the OR library set. Where available, click on the ellipses (three dots) to open a second window which will display the current library options. We recommend you find the most closely matching default library entry and use that as your base to create your own entry. Copy and paste your new entry, rename the entry, and then begin changing the settings to match what you have verified in the field. Please include detailed and accurate information in the Notes section that clearly explains what is going into the assembly you have just created. The QA team will be double checking all custom entries to make sure they are set up correctly. If you have any questions about correct set up please contact NewHomesTechnical@csgrp.com. 4

5 5) What entries in REM/Rate cannot be changed from their default settings? As much information as is available should be entered into REM/Rate. Keep in mind, there are some static fields that do not change: Rim/Band Joist Properties Insulation Grade must always be set at 1. Above-Grade Wall Properties Exterior Color drop-down must remain at Medium. Window and Glass Door Properties All Overhang Information must remain at 0 and interior shading must remain at the defaults of 0.85 for Winter and 0.70 for Summer. Ceiling Properties Ceiling Area (sq ft) and Attic Exterior (sq ft) must have the same square footage. Exterior color must be medium and radiant barrier, clay/concrete roofing and sub-tile ventilation drop-downs must remain at No. Mechanical Equipment Properties Programmable Thermostat must always be selected for heating and cooling. Duct Leakage Always model as CFM@50Pa. Total leakage to outside and total duct leakage must have the same test out results. Whole House Infiltration Shelter class must remain set at 4. Ventilation Strategy for Cooling This drop-down must remain at Natural Ventilation Lights and Appliances Refrigerator must remain at 775Wh/yr unless verified and listed differently on the 640S. The Dishwasher EF must begin at 0.65 and work up from there for ENERGY STAR qualified dishwashers. Range/oven fuel type must match the heating source. Clothes dryer location must remain conditioned and dryer fuel must remain electric. Dryer Eff. factor must remain at Use the REM/RESNET defaults for all other data points. Drywall Thickness Must be entered as The only other pages that may be completed beyond the Appliances page are the Mandatory Requirements page and solar pages, both Active Solar System and Photovoltaic Energy Systems, where applicable. The inputs that either remain static or that are unused (e.g. Detailed Lights and Appliances) cannot claim savings or incentives through Energy Trust s New Homes program. 6) Can I model heat pump water heaters? Yes, the unit must be listed on the Northwest Energy Efficiency Alliance s Northern Climate Qualified Heat Pump Water Heater list Please use our default heat pump water entry in REM/Rate regardless of water heaters EF. 7) How do I model a Heat Pump in REM/Rate? Currently, to compensate for how the modeling software counts energy consumption for heat pumps, please size to the following guideline: Run the Quick Analysis (lightning bolt or first option under Reports) to determine the Design Load for heating. We are only concerned about the heating design load for sizing of heat pumps. Use the heat pump size that is ½ ton (6K) larger but not greater than 1 ton (12K) larger than the design load given for heating, 5

6 regardless of what is actually installed on site. This allows us to be consistent and align consumption numbers with what is typically seen in Energy Trust territory. When modeling both standard ducted and mini-split heat pumps, collect the model numbers from the installed equipment and model the efficiency ratings listed in the AHRI Certified Products Directory. You will need both the outdoor compressor and air handler or mini-split head model numbers to get the most accurate efficiency ratings. The model numbers and efficiency ratings must be documented in the 640S/Axis Checklist. Ducted air-source heat pumps: Model as one entry: Select library type as Air-Source Heat Pump and selected the equipment from the OR library set. If you are unable to find an entry that matches what you verified in the field please select the closest entry available and copy/paste to create your own custom entry. Size the air-source heat pump following the details above. Ducts need to be added in duct screen for heating and cooling. Non-ducted mini split heat pumps: Model as two separate entries: Space Heating and Space Cooling: System Type Air Source Heat Pump. Size both the heating and cooling entries of the mini split to 6K larger than the heating design load as detailed above. No electric auxiliary attached to heating or cooling: If multiple units are to be installed, list the number of units installed. Ducts need to be added in duct screen for heating and cooling. Locate ducts inside conditioned space. List the total duct leakage to the outside as 0 CFM. Ducted mini split heat pumps: Model as two separate entries: Space Heating and Space Cooling: System Type Air Source Heat Pump. Size both the heating and cooling entries of the mini split to 6K larger than the heating design load as detailed above. No electric auxiliary attached to heating or cooling: If multiple units are to be installed, list the number of units installed. Ducts need to be added in duct screen for heating and cooling. 6

7 8) How do I model HRV/ERV systems? On the Infiltration/Ventilation page of REM/Rate select Balanced as your mechanical ventilation type. You will need to know the HRV/ERV specifications to complete the rest of the entries in REM. To find accurate specifications search the make and model on via the products directory. Once you have found the correct model, find the air flow rate (cfm) that most closely matches the calculated Simplified ASHRAE ventilation for the home you are modeling. You will need to model the air flow rate listed on the HVI site, the Apparent Sensible Effectiveness*, ASE, and the fan wattage for the selected air flow rate; use a default run time of 6 hours per day. *REM/Rate currently has a typo in its software which indicates ASE as Apparent Sensible Efficiency. This is incorrect and should read Effectiveness. For example: Based on the Simplified ASHRAE ventilation calculation a home needs 50 cfm of ventilation. From the HVI Model Details for the selected HRV, the closest rated CFM is 52 cfm, use the net airflow (cfm), power consumed (watts), and Apparent Sensible Effectiveness (%) listed on HVI in the REM model. 7

8 9) How do I model adiabatic wall systems? Create your adiabatic wall entry in REM/Rate under the Above-Grade Wall Properties Summary page. Select the correct adiabatic location in REM/Rate. If the adiabatic wall assembly is verified in the field to have an air space between both units then you should only model the section between air space and conditioned space. Do not model the entire assembly as one wall if an air gap exists. If no air gap is found during verification then you may model the entire wall assembly as one entry in REM/Rate for both units that share the wall. Required vs. Optional fields on the AXIS checklist/640s Required fields on the AXIS checklist/640s are the minimum fields required to complete a preliminary EPS in AXIS. You must at least fill out these fields and upload/export a REM/Rate.blg and UDRH file into AXIS to view an accurate preliminary EPS. Optional fields must be completed if they are captured in the model and savings will be claimed from them when calculating the EPS and incentives for your project. The majority of optional fields will need to be completed when submitting homes for final EPS quality assurance. If it is modeled then it must be captured on the AXIS checklist/640s. Some optional items that need to be filled out in order to be used in the model or in processing: Solar Ready status, Insulation details if more than one type or R-Values installed, Air Conditioner model number and efficiency, Refrigerator or dishwasher model numbers if more efficient than default, etc. ADU Requirements Accessory Dwelling Unit, ADU, refers to a structure that is permitted as an accessory dwelling unit by the local jurisdiction and is intended to be used as living quarters, i.e. bedroom, kitchen and bathroom, plus has its own USPS mailing address. ADU requirements ADU must have its own USPS mailing address separate from main residence ADU must receive its own third party verification ADU must be detached from the main residence ADU must be intended to be used as a residence Detached structure must be permitted as an ADU ADU must adhere to square footage limitations set forth by local jurisdiction Builder or owner builder must be a trade ally with the New Homes program Attached ADUs are recognized by the New Homes program when they are built as part of a new home. Currently the attached ADU does not receive an individual EPS and incentive but rather is included in the main home as described below. Attached ADU s: Surface areas, floor areas and volume of attached ADUs are treated as part of the entire house and are modeled as part of the entire house. Insulation, glazing and other envelope details specific to the ADU must be included in the model. Mechanical details for the ADU do not need to be modeled in the REM file. Instead, simply model the main building mechanical equipment sized according the building loads; the heating, cooling and water heating loads will reflect the occupancy and space/volume of the ADU and the main home. A separate blower door test is not required for attached ADU, simply apply ACH50 (not CFM50) from main body of house to the volume of the entire volume of building. 8

9 AXIS help If you are having issues within AXIS please open up a helpdesk ticket via the support link within the platform. This allows the support team to track problems as they arise and respond to you in a more timely manner. If you are having problems getting a response after opening up a helpdesk ticket please NewHomesTechnical@csgrp.com and include information of the problem you are encountering. 9