Locating buildings and offices with ample access to daylight, such as using glazed interior partition walls in the Andlinger Center for Energy and the Environment, saves energy. Similar to opening your blinds at home, we engineer our spaces and lighting controls to take advantage of free sunshine.
Operating appliances, think refrigerators running 24 hours a day, costs money and requires a great deal of electricity. Choosing energy efficient Energy Star appliances for all our projects across campus helps us save on both.
Using advance lighting sensors and controls, such as automatically turning off lights in unoccupied areas, we save energy with very little effect on work areas. Then we add next generation LED-based lighting, which is even more energy efficient than a compact fluorescent bulb (CFL).
Solar panels of course generate electricity, and when strategically placed, solar panels can also help divert hot sun away from a buildings interior. The photovoltaic solar panels placed above the glass roof of our new Frick Chemistry building serve double-duty by generating a limited amount of electricity as well as providing shading for the atrium.
Heating and cooling
Flowing already cooled air into laboratory spaces minimizes air conditioning of outside air. Lab spaces need a constant source of fresh air, yet not at the same temperature comfort as building occupants.
Understandably, a warm dorm in the winter and a cool office in the summer are basic expectations. We select equipment designed to produce more cooling for less money, saving both money and the environment in the long run. Also, our digital thermostats and sensors throughout campus automatically set and adjust heating and cooling temperatures, based on many factors including occupancy and conservation targets of heating to 68 in the winter and cooling to 78 in the summer.
Geoexchange energy is the heat from the earth; it is clean, reliable, sustainable, and cost effective. By tapping into the consistent 50 to 60 degrees below ground, a geoexchange system will bring earth’s heat up in the winter and cool hot air in the summer. If interested in reducing your utility bills by 40-60%, you too could try this at home. Princeton is converting to a district hot water system to replace our existing 100-year-old campus wide district steam system. The current system uses non-renewable technology and conventional equipment which burns fossil fuels to produce heat. This campus conversion will be achieved by drilling over a 1,000 geo-exchange bores, installed 600 – 850’ below ground; installing over 13 miles of distribution piping; building new plants and upgrading existing plants and converting our existing building systems. The geo-exchange bores form a closed-loop system which acts as a thermal “piggybank” below the ground. Heat-pumps are used to retrieve this thermal energy, heat or cool it and pump it out to our campus. Converting our campus to geo-exchange technology is a major component of becoming Net Zero by 2046 (300th Anniversary).
Turning the roof of a building into a living, green area leads to many sustainable benefits. With greater insulation, we save energy. With more living plants, we decrease stormwater run off and improve air quality. And by installing green roofs, we use our Campus as a Living Lab to educate and inform our students.
Provides fresh air and improved climate control, saves energy by reducing heating and cooling
Keeping a building’s indoor climate well maintained is a science, a building science. Of course a building’s outer shell needs to maintain a dry, heated/cooled and well-ventilated interior environment. We then need to include heavy insulation and sun shading to obtain a high performance exterior. For example, the exterior glass of Sherrerd Hall provides shading from the sun with fins embedded inside the glass. Look closely and you may just see them.
Utilizing superinsulation, airtight envelopes, energy recovery ventilation, high performance windows, and managing solar gain to maximize energy efficiency.
Radiant panel heating system in office spaces for energy conservation.
Siting, landscape & materials
When designing our buildings, both inside and outside, we incorporate sustainable materials whenever possible.
The new transit plaza blends a variety of options to get to and from campus, including bike racks and rentals, car permit and metered parking, pedestrian paths, buses, and of course trains.
We are proud to say we have at least four bike commuters amoung our Facilities staff. To encourage even more cyclists, more buildings on campus are being built with shower facilities.
Putting that annoying drip from air conditioners to good use reduces our demand for municipal water. When collected 24 hours a day/7 days a week, the water produced from the cooling and dehumidifying the air can add up to huge environmental savings.
Flushing a conventional toilet uses about 3.5 gallons or more of water per flush. New low-flow toilets use only 1.6 gallons or less of water, saving at least 45% of water on EVERY flush! And when we add low-flow showerheads and faucet aerators, we reduce our demand for water dramatically.
Similar to a rain barrel some of us have at home, only on a much larger scale, we capture rainwater and re-use it for plumbing, landscaping, etc. In the Frick Chemistry building we combine rainwater with condensate, color it blue and use it to flush ALL the toilets. We will also divert rain water recovered from our Arts project to use in our energy plant cooling towers. Oh, and rain water is free.
Designing a sustainable campus means looking at space outside our buildings as well. Low impact development considers techniques such as strategic site design, reducing stormwater run-off and functional landscaping. Various systems on campus relocate water run-off into perforated pipes that allow water into the soil and into rain garden planting areas instead of storm drains. Rain gardens both retain and filter stormwater, providing benefits to the local watershed and stream systems by encouraging stormwater infiltration and reducing erosion. We also have green roofs and planted areas over structures that filter the water and contribute to our goal of reducing campus stormwater run-off 'down the hill' into the lake.