Campus Energy Visualization Highlighted in Lunch Seminar

Posted on March 1, 2017

"We want to make it easy for you to know how much energy you're using right now," said Savraj Singh ‘03 in his opening remarks about Tiger Energy, a live energy dashboard developed by his company, Wattvision. Singh presented the visualization tool that he developed in partnership with the Office of Sustainability to a group of students at a Campus as Lab lunch seminar last month on energy data visualization efforts on campus.

lunch seminar

Tiger Energy and Campus Energy Systems

Tiger Energy, which breaks down campus energy data into easily understandable graphs, is the product of a several-year effort to help answer such questions as: Which buildings on campus use the most electricity? Where can energy improvements be made?

While giving a tutorial of Tiger Energy, Singh highlighted key features of the campus energy systems such as the campus cogeneration plant, which uses a fighter jet engine to power half of campus. To contextualize this energy output, Singh pointed out that an airplane requires four jet engines to power.

The jet engine turbine produces electricity for the campus, and then the excess heat is recovered to produce steam and chilled water for heating and cooling, boosting the energy efficiency of the cogeneration plant from around 30% to 75 – 80%.

Furthermore, he explained how campus energy supply is managed for optimal cost efficiency. Every 15-minutes, software informs the operational strategy by comparing the cost associated with running the campus energy plant turbine with the cost of purchasing electricity from the grid.

Under conditions when demand is low and it is cheaper for the energy plant to produce electricity, Princeton can sell excess electricity back to the grid. Singh showed how this phenomenon can be viewed on Tiger Energy by hiding the campus power plant on the overall energy supply chart as shown to the right.

Tiger Energy and Dorm Energy Competitions

Singh also highlighted the functionality of Tiger Energy as a residential college ranking tool. Once only available for one month during the annual Do it in the Dark competition, now students can run energy competitions at any time. The Office of Sustainability purposely arranged for the rolling competition to encourage long-term behavior change after a study showed that the energy reductions during Do it in the Dark disappeared once the competition ended. Tiger Energy’s ranking calculation equitably compares usage patterns among the colleges by calculating each college’s average usage in the current week to its own baseline, which is an average of the prior two weeks.  

However, the calculations do not account for changes in outdoor temperature. To more accurately compare energy usage in one week compared to the average of the two weeks prior, students can incorporate weather-normalized calculations into the ranking formula.

Princeton's Heat Map

Students have completed projects in the past with the same data feed used to create Tiger Energy. For example, Gina Talt ’15, Campus as Lab fellow, gave a tutorial of an energy Heatmap which was initially created by three computer science students for a course project. The Heatmap is another visualization tool that shows quick snapshots and trends over time of energy usage in different buildings on campus.


The information is shown on a base map of the campus, which is maintained by Matt Woodmansee, who also spoke to the students. Woodmansee is the space manager in Princeton’s Facilities department who oversees the University’s GIS implementation plan. He is in the process of updating campus infrastructure maps, and would welcome student collaboration on advancing projects such as refining the Heatmap to include data for more buildings.

The seminar ended with an open discussion in which attendees discussed potential ways to improve and expand upon Tiger Energy and the Heatmap platforms, as well as strategies on how to make students more aware of these tools. Katja Luxem, a graduate student in the Geosciences department, recommended incorporating Tiger Energy and the Heatmap into the Princeton mobile app.

The Office of Sustainability shared further project ideas that are also available on the Campus as Lab Research Questions page.