CBE researchers, students and visiting scholars will present recent findings and design tools at the 2020 ASHRAE Winter Conference, February 1-5 in Orlando. If you are attending the event we hope you are able to attend these sessions and catch up with our team members. Below we provide overviews of their presentations
Indoor Environmental Quality with an Emphasis on Thermal Comfort
Sunday, February 2nd at 11:00 am – 12:30 pm [Paper Session 4]
CBE researcher Tom Parkinson will present “Spatially Uniform Comfort from Ceiling Fans Blowing in the Upwards Direction,” co-authored by CBE researcher Paul Raftery and former graduate student Elaina Present. The researchers measured air speeds at 15 locations where occupants would typically be located, in a large shared office with furniture. They varied the fan speed and direction, blowing upwards or downwards. Tom will discuss the results, which suggest that despite lower air speeds, fans blowing upwards can provide more spatially uniform thermal comfort under elevated air speeds, requiring less consideration of occupant and furniture placement relative to the fan.
Show Me the Money! Cost-Based Control of Supply Air Temperature
Monday, February 3rd at 11:00 am – 12:00 pm [Seminar 37]
CBE researcher Paul Raftery will present “Field Evaluation of Cost-Responsive Supply Air Temperature Reset in a Large Office Building.” This project investigates whether a cost-responsive supply air temperature control strategy for multi-zone variable air volume systems is simple enough to implement within existing building management systems, and if the results are worth it. Over a six-month randomized, repeated crossover trial period, the team compared a new cost-based strategy to the industry best-practice control strategy in an office building. The new control strategy showed substantial energy savings, with little initial expense, and was determined to be much less complex than other approaches the industry has been hesitant to adopt.
Best Practices for Ceiling Fan Comfort Cooling
Wednesday, February 5th at 8:00 am – 9:30 am [Seminar 58]
In this session, three CBE researchers will discuss their work on comfort with ceiling fans:
Paul Raftery will present “Publicly Available Ceiling Fan Design Guide and Tool,” describing a free online resource to aid in understanding and designing with ceiling fans. It consists of a design guide — covering aspects such as benefits, considerations, constraints, costs, controls — as well as an online design tool. This manufacturer-agnostic tool allows designers to rapidly develop and browse through a set of valid ceiling fan design solutions for a given room. For each solution the tool estimates the resulting distribution of air speeds and the associated comfort implications. The underlying data is based on numerous full-scale laboratory tests.
CBE graduate student Dana Miller will present “Staging Ceiling Fans and Air Conditioning for Energy Savings and Comfort.” This presentation will discuss the design strategy of staging ceiling fans and air conditioning, highlight existing built projects using this strategy, and share results from a multi-year field study where staged operation was implemented as a retrofit. The field study included the installation of 100 highly efficient ceiling fans in small offices, community rooms and multifamily housing in existing buildings with air conditioning in a hot and dry climate. Fans operated based on temperature and occupancy sensors. Preliminary results from monitoring of air conditioning energy use, air temperatures, and occupant surveys demonstrate significant energy savings while maintaining occupant comfort.
CBE visiting scholar Sonja Salo will present “Human Interactions with Ceiling Fans and Smart Thermostats: Learnings from Case Studies in Office Buildings.” Smart thermostats have the potential to adapt to users’ thermal comfort preferences and save energy, and can also integrate with additional devices controlling the indoor environment such as ceiling fans. However, human interactions with ceiling fans and thermostats can differ from the design assumptions, resulting in unwanted comfort and energy effects. In this presentation, experiences from human interactions with smart thermostats and ceiling fans deployed in a field study are reviewed based on interviews and usage data. Suggestions to improve thermostat and ceiling fan control will be summarized.