A N ( A P P R OAC H A B L E )
I N T R O D U CT I O N TO
N E T Z E R O E N E R GY
by Alex Sassoon, PE, LEED AP, WELL AP
My favorite part of being an engineer is starting a new
project. It starts with an idea, a need. People need
somewhere to work, or live, or learn. The design team
takes those needs (called the Program in archispeak) and
develops a vision.
The challenge: design a building for the 21st century. But
does that mean to design based on the two decades that
have passed, or in anticipation of the eight decades to
come? The future of course!
Developing this vision requires the entire team to be at
their most creative. And that’s why I advocate Net Zero
Energy.
A Net Zero Energy building is energy efficient first. We
then offset its annual energy use with renewable energy.
But you may be thinking: what about other green
building standards? They have their place, but Net Zero
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Energy offers two major benefits: simple certification with
no fees, and guaranteed performance. You don’t want to
put the effort into the project, pay for the certification,
and get a building that isn’t energy efficient! You want
a return on investment with minimal cost. And if it’s your
dream for a LEED® Platinum, Living Building certified
project, Net Zero Energy helps you achieve both!
The two most important things to understand about Net
Zero Energy are energy use intensity and source energy.
Energy use intensity allows us to compare different
types of buildings. Source energy allows us to compare
different types of energy.
We use a building’s energy use intensity (EUI) to compare
energy efficiency on a level playing field. It’s expressed
in kBTU/SF-yr, which is BTUs of energy per square foot
per year. Even though electricity accounts for a lot of
energy use, we use BTUs because it makes more sense