Post Occupancy Performances

What is the connection between building occupant satisfaction and sustainability? What are some examples of sustainable design strategies that lead to higher occupant satisfaction and also contribute to resource savings?

The connection between building occupant satisfaction and sustainability are captured through introducing design solutions that allow building occupants to make changes to the environment they work in to satisfy their comfortability demands, which in turn have influence on the buildings energy savings in a positive direction. Researchers at the University of California, Berkeley’s Center for the Built Environment were able to test this through what is known Personal Comfort System. In the “Office too hot or cold? Researchers aim for comfort, energy efficiency” article by Kathleen Maclay she explains that the systems are made up of tools such as “energy-saving sensors that turned off when a space is not occupied…conventional space heaters… [And] foot warmers”. By having direct control over, the tools that target the most thermally sensitive parts of the body, the environment users work in, to satisfy and capture their comfortability levels; they have direct control over the temperature of their surroundings and impact the buildings performance and energy outputs. This system was predicted to have number of estimated cuts and savings in natural gas and electricity usage (for heating, ventilation and air conditioning) which would decrease a typical commercial buildings carbon footprint and save up to millions in energy cost.

Why are benchmarks/targets critical for analyzing actual building performance data?

In Hitting the Whole Target: Setting and Achieving Goals for Deep Efficiency Buildings paper benchmarks/targets are critical for analyzing actual building performance because they act as a goal that “expand from the a limited set of building systems addressed by traditional codes and standards, to an all systems accounting of energy use… [And] intent to assess performance relative to targets as-operates (measured) in addition to as-designed (modeled).” This allows for the energy of a buildings infrastructure to be planned out to reach said goal and not be restricted by code and standards, as more measured data can be considered and used to support the model and performance objectives to steer designers in the right direction for accomplishing a zero net energy building. If more data is entered into the model as a goal to reach the actual building performance and these are measures are reached, this data can be used as an accurate resource for the next buildings to come rather than having a rule of thumb of information that lacks measured performance and can lead to misallocation of information.

What are some of the limitations of traditional energy models when it comes to predicting actual building performance?

The two limitations of traditional energy models as stated in Hitting the Whole Target: Setting and Achieving Goals for Deep Efficiency Buildings paper are that they “only address a fraction of the energy-using systems in the building… [And] are only as good as the assumptions about operating conditions and building management practices.” The first limitation is due to a number of building sub-systems being left out of model. These include “plug” loads, savings that are not implemented, along with a number of other factors because of the energy-efficiency rules complexity which end up leaving a gap in the data collected. While the second factor is because the facilities operations and equipment are not being carried out as the assumptions made for the energy model, these are typically standard assumptions, which in turn provide inaccurate estimations and unrepresented data. Modeling analyst therefore do not expect the actual buildings to perform as predicted in the models made.