The built environment is defined as places built and designed by man, and in terms of energy consumption primarily consists of buildings, which account for 40% of national primary energy and 33% of national greenhouse emissions, or 2,300 MMT of CO2 eq., annually.  With roughly 70% of U.S. building stock pre-dating key energy efficiency policy, energy service providers have enlisted informational strategies to curtail demand-side energy consumption.  Topics in this research area includes holistic energy audits, the barrier-motivator nexus, small commercial energy disaggregation and building design.

Energy Efficiency in the Built Environment

Holistic Residential Energy Audits

Homeowners experience multi-faceted barriers to adoption of energy efficient technologies and appliances, including informational, financial and behavioral.  Research has demonstrated that targeting a single barrier is not sufficient to stimulate investment in all homeowners.  


In response, the National Energy Leadership Corps (NELC), developed and implemented course curriculum to train students in residential energy and holistic energy assessments.  Course continent was developed using flipped classroom pedagogical design.  Modules were developed and provided to students through a web-based platform where students completed video lectures, module quizzes, and pre- and post-module questionnaires to gauge students' perceived learning and confidence in the lessons' material.  One research question that emerged from this work was if students could learn complex systems thinking through a flipped-classroom.  To answer this question, analysis of the pre- and post questionnaires, final course reflection survey and College and University Classroom Environmental Inventory was performed.

Apart of the NELC design was the integration of holistic thinking to energy assessments, where homeowners' worldviews, interests and building needs were considered in addition to traditional costs analysis, when recommending energy efficiency measures (EEM).  The culminating experience for students was the energy assessment, where students entered homes to perform and deliver an informative energy assessment report.  Between 2012 and 2015, students completed a total of 120 energy assessments.  Recommended energy efficiency measures had potentially real impacts on homeowners' energy bills.  A post-assessment survey was delivered to homeowners to quantify homeowners' investments in the recommended EEMs and other "catalytic" investments potentially influenced through the homeowners experience with the students assessors.  Post-assessment surveys revealed homeowners' perceptions on barriers and motivators to adopting recommended energy efficiency measures and implementing self-identified measures.

Homeowner survey responses on their perception of envelope improvements (e.g. insulation, windows, etc.) in six categories, organized by those who adopted the envelope EEM and those who did not.  The six categories are: potential to save money, improve comfort, fits within their budget, have available time to implement, have the necessary information, have the skills to implement, and the recommendation is a priority to the homeowner.

Small Commercial Building Energy Quantification

The small commercial building sector, consisting of commercial buildings under 50,000 ft2 in floor area, represents 94% of all commercial buildings by number and is accountable for roughly 45% of the commercial sector's total primary energy consumption.  Though, small commercial buildings are largely underrepresented in research and underserved by the building efficiency community.  The focus of energy efficiency research and investments have targeted larger commercial buildings where homogeneity of building stock support a "one-size-fits-all" approach to energy sciences and large commercial buildings typically have access to capital to invest in energy efficient technologies.  However, with the realization of the small commercial building's role in national and global energy consumption, research is emerging on how to engage and improve a sector that lacks access to capital and suffers from extremely heterogeneous building stock, e.g. building use (restaurant, office), state of renovations, and occupants.

To address building stakeholders's immediate needs, the development of a Building Energy Assessment Resource (BEAR) employs bottom-up energy quantification, assembling disparate resources intended to provide building stakeholders with meaningful energy information to support informed decision making.  Further, energy contour plots have been conceptualized intended as a visual informational resource for consumers, with applications ranging from manufacturer labels to whole-building performance analysis.

Energy Contour Plots

These visual resources plot the complete energy potential of an appliance in contours as a function of active mode power (W) and hourly operation in active mode (hr).  Active power mode ranges from zero to the maximum potential power equal to volt-amp, and operation ranges from zero to 24 hours.

Illustrated is an example of a desktop computer tower where (A) represents the BEAR estimated energy use from user input data (note: the line made at the border of blue and white region represents all possible combinations of power and operation that equals the BEAR estimated daily energy use), (B) represents an increase in power (i.e. word processing versus live streaming video), and (C) represents an increase in hourly operation (i.e. an employee workstation computer versus a dedicated network computer).

Funding Sources
Associated Publications

Marks, J., Ketchman, K.J., Bilec, M.M. (2014). "Understanding the benefits of the flipped classroom in the context of sustainable engineering." ASEE Annual Conference and Exposition, Conference Proceedings.

Ketchman, K.J., Khanna, V., Riley, D., Bilec, M.M. (2016). "Evaluation of a Holistic Energy Assessment Program." Procedia Engineering, 145, 468-475. doi:

Ketchman, K.J., Khanna, V., Riley, D.R., Bilec, M.M. (2017 submitted), “A Survey of Homeowners’ Motivations for the Adoption of Energy Efficiency Measures: Evaluating a Holistic Energy Assessment Program.” ASCE Journal of Architectural Engineering

Ketchman, K.J., Parrish, K., Khanna, V., Bilec, M.M. (2017 submitted), “Synergizing Disparate Component-level Energy Resources into a Single Whole Building Tool to Support Energy Conservation Action in Small Commercial Buildings.” Energy and Buildings

Ketchman, K.J., Khanna, V., Parrish, K., Bilec, M.M. (in progress), “Evaluation of the Sources and Measure of Uncertainty in Appliance-level Electricity Energy Estimate Resources in a Food Service and Office Small Commercial Building.”