The idea of net-zero buildings has been around for years as an alternative to traditional buildings, which now consume about 40% of total fossil fuel energy in the US and the European Union.

However, recently, net-zero buildings have become more popular, says Christopher Schaffner, instructor of HeatSpring’s Energy Modeling in EQuest course. These structures return to the grid at least as much energy as they consume, and Schaffner teaches his students how to model energy consumption in them.

The number of net-zero buildings across the US and Canada has grown nearly 700 percent since 2010, spurred primarily by private sector investments, according to the New Buildings Institute.

Thirty-nine Percent Growth Rate Expected by 2021

According to a report for Technavio, the global zero-energy buildings market is expected to grow at a compound annual growth rate (CAGR) of about 39 percent by 2021.

“While definitions of net-zero buildings can vary, the basic idea is that over the course of the year, your building consumption and production are balanced,” says Schaffner, president of The Green Engineer and a part-time lecturer at Northeastern University.

In addition, the U.S. Green Building Council (USGBC) has announced a new certification called LEED Zero, which rewards net-zero carbon, energy, water, or waste – as long as buildings are certified under either LEED for building design and construction or LEED for existing buildings. Under the program, the USGBC requires one year’s worth of performance data to verify net-zero status for green buildings.

“Most of the building regulations are using net zero as an energy target,” he says. “Some, like Architecture 2030, allow carbon neutral, but set limits on the savings that can come from offsets.”

Cities Show Their Support of the Net-Zero Building Trend

What’s more, large cities are throwing in their support of the net-zero building movement with new goals. For example, Washington, D.C. recently announced a goal of converting all existing buildings to net zero by 2032, and New York City announced plans to retrofit existing buildings in order to achieve a 50 percent reduction in energy consumption by 2030. 

To support such goals, modeling with software systems such as EQuest helps industry members design net-zero buildings. It’s especially helpful in showing how changes in design alter the amount of electricity needed to heat or cool a building, says Schaffner.

Modeling Allows You to See the Impact of Weather Patterns

For example, with computer modeling, you can change the amount of insulation or switch out  heating systems, all while running the model against the weather patterns of the building’s exact location.  You can even use future weather models to see how changes to the buildings will affect electrical needs over time. It’s also possible to get a feel for the possibilities that global warming brings to the local weather, he says.

While the EQuest energy  modeling software is free for anyone to use, it has a steep learning curve, and Schaffner’s course focuses on helping engineers, designers, or architects navigate the software and configure their buildings. The software models running the building for a year, calculating the hour-by-hour energy consumption, and includes an annual energy consumption broken down by the time of day and year. Schaffner helps his students learn the ins and outs of the modeling software and the variables that can affect the model’s outcome.The program can build any utility program into it, including the time of day and peak demand so that the user can work on demand management.

For industry members eager to jump on the net-zero bandwagon, Schaffner focuses on the how-to’s of running the software and also serves as tech support while his students are learning about the freeware, which doesn’t come with tech support. Along the way, his students learn how to use the software to model all kinds of buildings, allowing them to create low energy buildings that can ensure a building attains the coveted net-zero designation.