Proposed Redesign

 

This sections objective is to discuss how the alternative designs listed above will be implemented within Agricultural Engineering Building. The major goals of the redesign is to reduce the buildings energy usage and maximize thermal comfort. This will be mainly done by maximizing the already highly efficient campus steam and chilled water loops. By taking advantage of waters ability to transfer more energy than air, Agricultural Engineering Building has the opportunity to improve upon its currently scheduled LEED Gold rating.

 

Radiant Floor Heating Currently all offices and conference rooms are grouped together throughout the building. The majority of offices is located in the renovation section and consists almost entirely of offices. The offices in the renovation section of Agricultural Engineering Building are grouped together with reception areas. This gives the advantage of providing less control to individual occupants which is typically a major concern with radiant floor heating. More than likely each office will not be occupied at the same time and only the reception area will have a guaranteed occupant. By separating blocks of 3-4 offices/reception areas to one thermostat, the occupants will more than likely be satisfied and this system will eliminate several VAV boxes and reduce ceiling height which will allow for the extra floor thickness. Energy usage can also be reduced by allowing water to carry energy as long as possible before being radiated into the space. Radiant floor heating will also improve thermal comfort by naturally allowing heat to rise into the space. With most of the offices and conference rooms located on exterior walls with windows, thermal comfort could become an issue after construction.

 

Active Chilled Beams For all zones within the building, active chilled beams could be considered an option. They would have their greatest effect during the summer cooling months for all spaces. In combination with radiant floor heating, offices and conference rooms would achieve the maximum level of thermal comfort possible. Active chilled beams can also reduce ceiling heights, as currently many of the buildings zones are supplied with either fan coil units or VAV boxes. By reducing ceiling heights there is potential to lower structure cost as well as provide additional room for radiant floor heating. Further investigation will be needed for some of the lab and shop zones. Some of the labs have cold and freezer rooms which may affect the chilled beams if they are too close to these spaces. Condensation on the chilled beam could lead to dripping and will need to be investigated. Shop spaces such as the wood and metal shops may have a high concentration particles in the air and could settle on the chilled beam, which will harm performance.

 

Recirculating air within Office/conference rooms and Heat Recovery By adding an additional air handling unit on the third floor, the office/conference rooms can be put on an air recirculating system to reduce energy consumption. The other benefit will be smaller duct diameters which will create additional mechanical space, and/or reduce structural costs. The two air handlers serving the DOAS have potential to also be replaced with slightly smaller units decreasing costs. Ductwork size can be reduced since the offices and conference rooms are all grouped together, and the DOAS would only serve the first floor and the interior zones of the second floor. A heat recovery unit just for the new third air handler would also reduce energy use. This heat recovery device could be placed next to the energy recovery unit in the third floor penthouse. 

 

Integration

Structural: The addition of the third air handling unit and heat recovery device will be extra load on the third floor penthouse structural system. This system will need to be evaluated in order to determine if the current system can support the extra load. The radiant floor will also cause an additional load on the structural floor and will need to be supported properly.

 

Electrical: With the addition of the air handling unit and reduction in the two current DOAS air handlers, the electrical configuration will need to be reevaluated. The removal of VAV boxes and fan coil units will also have a major effect on the buildings electrical system. Radiant floor heating will also require additional pumps and controls in order to work properly.