Cara Lyons ’11 Analyzes the Costs of Building Green

Civil engineering major and Division I athlete writes about her work with Kristen Sanford Bernhardt, assistant professor of civil and environmental engineering

Cara Lyons ’11 (New Holland, Pa.) is working on EXCEL research with Mosi London ’10 (Brooklyn, N.Y.), and Kristen Sanford Bernhardt, assistant professor of civil and environmental engineering, looking at how designing a sustainable building impacts its cost. The project is supported by a grant from the National Science Foundation. Lyons, a civil engineering major, is a member of the College’s Division I field hockey team.

The push for sustainable and “green” building in the construction of facilities continues to increase as we approach a new decade of the 21st century. While “green” attributes reflect positively on a facility, initial cost estimates are often a deterrent to environmentally friendly construction.

To encourage green building in the public sector, an agency may be willing to spend more than what it would budget for a conventional building. However, this concept reinforces the perception that green buildings are more expensive. This may often be true on the basis of initial capital cost, but green buildings may be less expensive to operate and maintain over time. Thus, the green option would be cheaper if the comparison was based on the total cost of ownership (TCO).

The goal of the project is to apply agent-based modeling to most accurately predict the TCO of a green facility. In addition to cost estimates, we hope to demonstrate social factors involved in a facility’s lifecycle by including interactions among the owner, designer, and contractor. Professor Sanford Bernhardt, Mosi London, and I have been focusing on the creation of a prototype model.

Our research team also consists of two professors and both undergraduate and graduate students at Virginia Tech. Their responsibilities are focused on data collection and the validation of the behaviors of the created model. In a few weeks, Professor Sanford Bernhardt, Mosi, and I will be traveling to Virginia Tech to meet with the entire team. Mosi and I will have the opportunity to do some field research, and the three of us will get a better idea of how to further improve the current model.

While a summer in Easton may not be a break from Lafayette, it has been an opportunity I certainly do not regret pursuing. Mosi, Professor Sanford-Bernhardt, and I have completed a significant amount of background research before applying concepts to our model. Using a program called Netlogo, the model displays three owners who choose from four designers and four contractors. The owners select the cheapest combination of a designer and contractor based on variables including experience, values, building square-footage, personality (or “greenness”), as well as cost. An owner’s level of “greenness” may be low, medium, high, or none. This characteristic is applied in order to account for a green owner being more likely to select a green designer.

Mosi and I are working to condense the code of the model and further evaluate the variables used to select combinations. In order to make the model as realistic as possible, we are searching for better estimates of key variables such as costs and building square-footage. We are doing some of the research on our own, but are planning to get significant information during our stay at Virginia Tech that will contribute to our accuracy.

As we continue to progress, we are getting closer to the goal of better predicting the total cost of ownership, which will ultimately show the benefit of green building. With a more accurate picture of the relationships between investment and outcomes, the goals of sustainability in public sector projects will become a reality. As a civil and environmental engineering major, this type of research will greatly impact my future and I am honored to be a part of this initiative.