The Spinnaker Group Inc.: LEED Consulting, Energy Modeling, Building Commissioning
By: Trevor Schatz, LEED AP BD+C
LEED Project Manager, The Spinnaker Group
This year at Greenbuild the term net zero seemed to be everywhere; in sessions devoted to a wide range of topics, mentioned in the speeches of the Mayor of Philadelphia, Rick Fredrezzi and Hillary Clinton, in the expo hall with product manufacturers, and overheard in the discussions of the attendees.
I too, previous to arriving at Greenbuild, had made learning more about net zero a priority. One of the more poignant sessions I attended was “The Power of Zero: Optimizing Value for Next Gen Green”. This presentation set the tone of the net zero discussion clearly and succinctly through discussing data sets and case studies past and present and the topics seemed to reverberate throughout the conference.
With the limited amount of net zero buildings growing everyday the data available has been increasing steadily over time and this year it seems to have crystallized with a real motivation to understand the features necessary to attain the elusive net zero goal.
A clear approach to net zero includes an understanding of operations, processes, and behavioral approaches that enable cost effective results. According to Peter Morris, for a net zero project to be cost effective, one third of the energy load must first be reduced through behavioral modifications of the building occupants, the second third must be reduced through the use of efficient HVAC systems coordinated comprehensively, and finally the final third of energy is generated onsite.
According to Lisa Matthiessen a third of net zero buildings only maintain that level of performance for the first 1-3 years. The actual costs of building to the next level of green are represented not only by design, construction, and maintenance costs but by human capital in the form of experienced building managers that learn which strategies yield the best long-term results. When personnel and/or ownership changes hands the lessons learned about operating the unique net zero building are often lost resulting in reduced performance.
Design and delivery strategies that can manage costs are also evolving to a critical level in which a wide diversity of buildings in many locations are now eligible to attain net zero energy use in a timely and cost effective way. Case studies were discussed of an office building in the Bay area, a warehouse in Seattle, and corporate headquarters in Portland that all attained net zero while serving many different uses in various bioregions.
Finally, through statistical analyses comparing the construction costs for the very greenest projects against industry standard projects, we can see that the gap is slowly closing, allowing for the introduction of a new way of evaluating high-performance buildings relative to energy and water goals and strategies; net zero.