EMA Member Al LaPera, CxA, EMP, LEED AP, Kimley Horn published “Decarbonization for Dummies” in ESMagazine.

Read Full Article

Decarbonization has become the new buzzword of the built environment community. This is not to say the concept or concern is new, it’s just now coming to the forefront. Talk about a misunderstood concept. In full disclosure, I am one of them who did not clearly understand what it truly meant. Throughout my entire engineering career, I’ve always designed projects with energy conservation in mind, almost solely having dedicated the last decade and a half of my career to saving energy. In the new lexicon, I was completely focused on reducing operational carbon (OC).

I was recently asked to speak at the local American Institute of Architects (AIA) chapter on this subject. While preparing, or “cramming for the exam,” so to speak, I learned decarbonization is much more than just reducing the energy consumption of a building, or what I previously denoted as OC.

To fully understand the concepts, this new terminology must be defined.

  • Carbon is greenhouse gases (GHGs), which are gases in our atmosphere that trap heat.
  • Decarbonization is essentially both the journey and the destination: reducing, then eliminating, the embodied carbon (EC) and OC of a building through:
    • Increased building design/construction and operational efficiency;
    • On-site renewable energy generation; and
    • Off-site greenhouse gas (GHG) emission offsets.
  • Embodied carbon (EC) is the CO2e1 associated with the building construction, including the extraction, manufacture, and transportation of building materials as well as its ultimate demolition.
  • OC is the CO2e associated with operating and maintaining the building throughout its lifetime. Most of this CO2e is associated with the energy used in building operations.
  • Net-zero carbon buildings use renewable energy production and other GHG offsets to reduce their CO2e to zero.

One can imagine how this threw my perspective into a minor tailspin. Once I started talking with some of my peers about how I felt, admitting I’d missed this complete concept, I discovered I wasn’t alone in this “lack of understanding.” During these conversations, I found many mechanical, electrical, and plumbing (MEP) engineers and architects, like myself, have only been focused on lowering OC (i.e., making buildings more efficient).

To fully understand this concept, one must understand the impact each component has as a whole and individually. First, one must be able to define what a metric ton of CO2 is. To supply some tangible scale, I used the EPA’s equivalencies calculator2 for some examples. The examples have been broken down by what emits it; what can be done to avoid it; and, lastly, what can be done to have it sequestered.

Examples of 1 Metric Ton of Emitted Carbon

  • 112 gallons of gasoline consumed (i.e., 2.6 Hummer fill ups @ 15 mpg average);
  • 1,101 pounds of coal burned;
  • 40.6 home BBQ propane gas cylinders; and
  • 188 therms of natural gas burned.

Examples of 1 Metric Ton of Avoided Carbon

  • 43 trash bags of waste recycled instead of landfills (i.e., using for an anabolic digester which emits methane); and
  • 27 incandescent bulbs switched to LEDs (based on 60-W bulbs converted to 10-W LEDs).

Examples of 1 Metric Ton of Sequestered Carbon

  • First, one must define carbon sequestration. Carbon sequestration is simply a way of removing CO2 from the atmosphere;
  • Approximately 17 tree seedlings growing for 10 years or approximately 165 planted seedlings per year; and
  • 1.2 acres of forest in one year.

Unfortunately, there is no way society can simply “plant its way” out of this dilemma. A power plant emits 1 metric ton in almost the blink of an eye. For some perspective, per the EPA, one average natural gas fired power plant emits 397,959 metric tons per year2. That’s the equivalent of 45.43 CO2e per hour or 0.76 CO2e per minute. And, coal-fired plants emit almost 10 times those amounts.

Read More

This article is based on a past presentation presented by Al LaPera with EMA. To view the on-demand video, click here.

The Energy Management Association (EMA) administers its ANSI-accredited, DOE’s Better Buildings® recognized Energy Management Professional (EMP) certification and provides an array of training and education programs to support the energy management profession. Visit www.energymgmt.org.