| ||Chicago Center for Green Technology|
This is a gut rehab’ of a 1940s office building that was originally designed for natural ventilation with long narrow wings for cross ventilation. In the 2003 renovation, a ground-source heat pump provides all space cooling and most of the space heating. There are no integrated controls between the operable windows and the mechanical system, and occupants are free to open/close the windows at their own discretion.
| || ||Carnegie Institute for Global Ecology|
Offices and research laboratories are conditioned with a combination of radiant slab heating & cooling, an evaporative cool tower, natural ventilation, and mechanical ventilation in the lab spaces. Chilled water is created from a night sky roof spray system. There are no integrated controls between the operable windows and the mechanical system, and occupants are free to open/close the windows at their own discretion.
| ||Chesapeake Bay Foundation|
This two-story open-plan office building includes low-level windows that can be operated by the occupants, and upper clerestory windows that automatically open. Outdoor temperature and humidity sensors determine when the climate is appropriate for natural ventilation, where upon the mechanical system is shut down, red/green lights notify the occupants they can open windows, and mechanical actuators open the clerestory windows to induce a draft.
| || ||Hewlett Foundation|
This building combines private perimeter offices with an open plan in the core. It used an evaporative cooling chiller in concert with an ice storage system to minimize energy costs during the peak demand periods of summer days. When sensors indicate the building should switch to natural ventilation mode, the cooling system shuts down, the clerestory windows are mechanically opened, and lights in the corridor change from red to green to tell occupants they can open the lower windows.
| ||Natural Resources Defense Council|
Situated in a warm/temperate climate, this building uses relatively little mechanical cooling. The displacement ventilation system is designed to provide cool air only where it is needed. The building has a real-time display that shows occupants about how much energy is being used (and generated by the PV) and where. Occupants can use the operable windows and clerestories at their discretion, with no controls connecting their use to the mechanical system.
| || ||Woods Hole Research Center|
A website shows real-time energy data and system performance to provide ongoing education to the building occupants and the public. Heating and cooling is provided using a ground source heat pump powered by solar panels, and the hydronic system either feeds water-to-air heat exchangers in the large common areas, or individually-controlled valence convectors in the offices. There are no controls between the mechanical system and windows, and occupants are free to open/close the windows at their own discretion.
| ||Bren Hall|
The four-story office wing, and three of the four floors in the laboratory wing were initially designed to be exclusively naturally ventilated. Air-conditioning was added to the laboratories and core offices by tying into the campus multi-building chilled water loop, supplemented by the building’s own chiller. The operable windows and transoms have sensors on the window frames that turn off the heating system when the windows are open.
| || ||Gap Office Building – 901 Cherry|
Utilizing an underfloor air distribution system, occupants have control not only of the operable windows, but also the floor diffusers. Lower windows combined with upper clerestories and louvers in the central atria help promote stack ventilation. These high level vents remove heat gains from lights, equipment and occupants. The building also utilizes nighttime pre-cooling strategy. Occupants can use the operable windows at their discretion, and there are no controls connecting their use to the mechanical system.