Energy performance is a top concern for many building owners. After all, an inefficient building can increase your utility costs and drain your operational budget. To achieve a high-performance space, you need to make informed decisions at every stage of the architectural process.
Utilizing energy modeling software is one way to improve a building’s performance. We incorporate high-level energy modeling at the beginning of every project, but some projects go a step further and utilize modeling throughout the design process to test a variety of decisions.
This article will explain energy modeling in more detail and outline how it’s used in each design phase, helping you understand its benefits.
What is Energy Modeling?
Energy modeling is the process of running a design through software to determine a building’s potential energy consumption. The goal is to find a design that offers the lowest Energy Use Intensity (EUI), the amount of energy used per square foot per year.
Throughout the architectural process, energy modeling allows you to compare options for both large and small-scale design decisions, including:
Orientation (alignment with the sun)
Building mechanical and electrical systems
Options are often weighed against initial costs and occupant comfort metrics, helping you make decisions that align with your project goals and budget.
Energy Modeling in the Architectural Process
Ideally, energy modeling occurs at every stage of the architectural process. It is most effective when you continuously test options and iterate on the best possible approach. In the early stages, you can test options for massing and orientation and later test more detailed design elements.
While we perform high-level energy modeling at the beginning of the process, more detailed models may require a third-party consultant. Depending on your location, some major utility companies will cover the cost of energy modeling.
If you take advantage of energy modeling, here’s what you can expect from each design phase.
Energy modeling begins with testing high-level design decisions. Your architect will test simplified versions of the design known as “shoebox models” and compare the predicted EUI with industry baselines and project goals.
Testing these models helps you find the most efficient size and shape for your building.
Along with shoebox models, you will test solar orientation options. Solar orientation is how the building aligns with the sun, and it can greatly impact energy efficiency and occupant comfort.
Energy modeling can help you find the best way to fit the building onto the site.
While keeping cost in mind, you will pick the best option and move forward with the design process. In Schematic Design, you start testing more detailed elements of the building. For example, you can test window placements and determine how different options impact performance, glare, and thermal comfort.
You can also set working assumptions for temperature and humidity and test thermal zoning strategies. Storage spaces, for instance, may have a different mechanical zone than regularly occupied areas. Supplying your architect with desired temperature assumptions and hours of operation can make EUI predictions more accurate.
Perhaps most importantly, you can test the efficiency of different mechanical and electrical systems in Schematic Design. For example, you may use energy modeling to decide between a geothermal, VRF, or rooftop system. Modeling these systems in conjunction with a life cycle cost analysis can help you find an option that meets both your performance and budget requirements.
As you test different design elements, the predicted EUI gets more accurate, helping you price items like solar arrays. With a predicted EUI, your design team can size an array and solicit bids from solar suppliers.
By the end of Schematic Design, the project should have a clear direction.
In Design Development, you will refine the options you explored in Schematic Design and choose products. For example, if you modeled window placement in Schematic Design, you can now model options for window treatments and glazing.
Throughout Design Development, you and your design team will choose specific products and systems. Your architect will solidify these choices with specifications in the Contract Documents.
In the Contract Documents phase, your architect will create drawings and specifications to explain the design intent to the contractor. While you are no longer testing options, your architect can use energy modeling to validate the choices you have made to date.
The Contract Documents phase is also an opportunity to start thinking about commissioning. Energy modeling is only effective if the final building operates as intended. A problem with your mechanical system, for instance, can increase your energy consumption.
A commissioning agent is a third-party specialist who inspects construction work and ensures everything is operating correctly. They will often check mechanical and electrical systems, including HVAC fans, thermostats, and lighting controls.
If you are wanting a more enhanced approach, you should consider consulting a commissioning agent as early as Schematic Design. In earlier phases, commissioning agents can provide their input on different building systems and their impact on operations and maintenance.
Although commissioning is an additional expense, it helps your building operate at peak performance and reduces the need for call-backs to the contractors after opening.
What Are Your Next Steps?
High utility costs can drain your operational budget. Constructing a new facility or renovating your existing space is an opportunity to improve your energy performance and lower your expenses. Energy modeling software is an effective tool for improving energy efficiency.
Early in the design process, you can expect high-level energy modeling related to the building’s shape, size, and orientation. As you progress through the design process, you will test different options for window placement, thermal zoning, and mechanical systems.
Energy performance is only one factor to consider during the design process. When modeling design options, remember to consider factors that impact occupants like thermal comfort. Learn more by reading about design strategies that improve occupant health and well-being.