This article maps the standards used and assumptions made for cove.tool's automated energy model generation.
How does it work?
Cove.tool follows 4 steps are below, as detailed flow chart demonstrates how they...:
First, based on the user's energy code selection, cove.tool populates code prescriptive values such as envelope, lighting, ventilation rates.
Second, for parameters like EPD (appliance use) , total occupants, and occupancy schedule the tool uses values listed in ASHRAE 90.1 - User's Manual.
Third, PNNL Model Prototypes are used to calibrate parameters not regulated by the selected energy code, such as LPD Unoccupied, DHW Demand, etc. Some energy codes after 2016 have begun listing parameters, such as Fan Control, Pump Control, and Sensors. All earlier version remains calibrated values.
Last, industry standard values are used to define any remaining values. User can edit these values so that they reflect the projects design intent.
For more information on Building System inputs see this article.
Talking to an Engineer
The resource above explains how defaults are populated into the platform. It's also important to keep in mind that cove.tool is an early-stage single-zone building performance app. It uses the ISO 13790 Heat Balance Engine and does not require a high level of detail.
Overall questions that cove.tool can answer:
Will this system type save me some energy?
While saving energy, does it have a payback?
Questions the tool cannot answer:
Should I have a fan coil in room #237?
What is the peak cooling load for my building?