eSim is a biennial conference for building performance simulation put on by the Canadian chapter of the International Building Performance Simulation Association (IBPSA). This year we were fortunate to have the conference hosted in our home town of Ottawa by researchers at Carleton University. It was a fantastic conference, attended by well over one hundred academics, researchers and professional simulators. Daniel and Clem represented Arborus at the conference with a paper on their experience with energy modelling in integrated design charrettes as part of the Enbridge Savings by Design program.

One of the highlights of the conference was a keynote talk by Guy Newsham from the National Research Council on the results of a study comparing energy and indoor environmental quality in 100 LEED certified buildings and 100 non-LEED certified buildings. The study relied on surveys of building occupants, extensive field measurements, and energy data from the first year of occupancy. The study found that green buildings score higher on aesthetics, views, ventilation and temperature and that occupants of green buildings tend to be in a more positive mood and have a better workplace image. Areas where green buildings underperformed conventional buildings included speech privacy and acoustics. It was encouraging to hear that the green buildings in the study used 25% less energy on average than the conventional buildings.

We were also struck by Liam Buckley’s talk on the dangers of relying on old weather data in this period of rapid climate change. His presentation compared the results of energy modelling in Toronto and Vancouver using the pre-1995 CWEC weather files which are based on 30 years of weather data and more recent TMY7 weather files which are based on the most recent 7 years of weather data. He found that big changes are happening at the extremes as the climate changes, with many fewer hours at the coldest temperatures in winter and many more hours at the hottest temperatures in summer. This change in climate will affect building design and equipment sizing now and in the future and should be taken into account as we consider the best strategies for energy efficiency going forward. Looking at the weather data for Ottawa shows that we have had an average of 4327 heating degree days in the last 7 years. This is a significant drop from the 4762 heating degrees days given for Ottawa by ASHRAE.

Curt Hepting presented a thoughtful analysis of the benefits and drawbacks of moving to an energy-intensity based system for analyzing the energy performance of buildings. We also came away impressed with the development of OpenStudio, an open source software package supporting energy modelling with EnergyPlus, and a companion iPad application called SimuWatt. SimuWatt looks like it could be a powerful tool for automating and streamlining the energy auditing process. Daniel was fortunate to attend two full-day workshops on OpenStudio given by Daniel Macumber and David Goldwasser of the National Renewal Energy Laboratory (NREL).

The organizers did an excellent job of putting together a thought-provoking program and highlighting some of Ottawa’s best food purveyors. All in all, we had a great time at eSim 2014.