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Energy Conservation Strategies

With added square footage comes added energy costs, but SDSU has made strides to control energy consumption through energy conservation projects and energy management strategies. The following is a list of practices and methods that the university strives for in as many projects as possible:

  • Energy Efficient Fluorescent Lighting – SDSU has done an extensive amount of energy efficient lighting upgrades to offices and classrooms around campus. Approximately 95% of the fluorescent fixtures on campus have been upgraded to more efficient bulbs and ballasts. These upgrades update the older T12 Fluorescent or Incandescent fixtures with more efficient T8 or T5 fluorescent fixtures. All new construction incorporates this technology as it is the industry standard. Our most recent building lighting upgrades have occurred in parts of Animal Science Complex and Yeager Hall.

  • LED Lighting – SDSU has started replacing its conventional metal halide wall packs with LED wall packs on a burnout basis. Over 75% of the wall packs on campus have been converted to LED. These LED fixtures consume much less energy and have a greater lifespan than conventional fixtures. The fixtures also require little or no maintenance for many years. LED fixtures have also started to appear in some of the parking lot light fixtures around campus. Indoor LED lighting projects have also become more popular with LED fixture being installed during classroom and office renovations as well as general lighting upgrade projects.

  • High Bay Fluorescent Lighting – SDSU has been upgrading its existing high-bay metal halide or mercury vapor fixtures with high-bay fluorescent fixtures. The fluorescent fixtures consume 60% less energy in some installations, and also have more consistent light output over the life of the bulbs.

  • Occupancy Sensors – SDSU has been installing occupancy sensors in classrooms around campus as they are upgraded or remodeled. These sensors will turn off the lights when the rooms are unoccupied. SDSU now has over 1,000 occupancy sensors on campus. A large majority of these have been installed during remodeling and new construction projects. Depending on the size of the room, these sensors will pay for themselves in 10 years or less.

  • Energy Star Products – SDSU abides by the Office of Procurement Management’s Policy ES-10 which states that all state agencies are required to purchase ENERGY STAR designated products if a product exists.  This policy went into effect in 2008.

  • Updating HVAC Controls – SDSU is in the process of updating the antiquated pneumatic equipment controls with digital control systems. Digital controls allow for more accurate measurement and control of the building equipment. This ultimately results in better occupant comfort and decreased energy use. All new construction incorporates this technology. Controls in the residence halls have also been upgraded or are planned to be upgraded to incorporate individual room temperature control. These controls reduce room overheating and have shown to reduce energy costs by one-third.

  • VFD Technology – SDSU has been incorporating Variable Frequency Drive technology to electric motors in mechanical rooms throughout campus. This technology varies the speed of these motors to match the varying output process. The electricity used by an electronic motor is a function of the speed of the motor to the third power. Therefore, if you can decrease the speed of a motor by 50%, you have decreased its power consumption by almost 88%. VFD’s are installed on almost all new construction on campus. SDSU currently has around 175 VFD drives installed.

  • Pipe Insulation – SDSU has done an extensive amount of work insulating bare or poorly insulated piping in the steam tunnels. By reducing the amount heat lost through these pipes, SDSU has decreased its energy input to the Central Heating Plant. At the end of 2012, all of the steam lines in the pipe tunnel have been insulated up to today’s standards. For example, in December of 2005, the average condensate return temperature at the Central Heating Plant was 126°F. In December of 2015, that temperature had increased by 32°F, for a return temperature of 158°F. This increased condensate temperature makes a big difference when the plant receives an average of 115,000 gallons of condensate a day. This increase in condensate return temperature saves about $185/day during the winter.

  • Steam Efficiency – SDSU has annual inspections of its steam system. Every year SDSU replaces numerous steam traps and repairs steam leaks in an effort to minimize costly steam loss. A typical failed steam trap or leak left alone can cost $500 annually in energy loss. These repairs pay for themselves within months.

  • Central Heating Plant – The Central Heating Plant heats about 85% of the buildings on campus (≈3,050,000 ft2). In 2012, the CHP went through some major renovations and upgrades. Two Natural Gas boilers were installed to replace older, less efficient Coal burning boilers. That marked the last time that SDSU has burned coal as an energy source. Direct Digital Control (DDC) systems replaced less accurate pneumatic control systems. Several forms of heat recovery systems were also installed at the plant to help reduce the amount of energy input the plant requires to produce the required steam. Some examples of these systems are using flue gas to preheat boiler feed water, using blowdown water to preheat makeup water and using a gas flame to preheat combustion air.

  • Chiller Plants – SDSU currently has one chiller plant with a second plant being constructed on the North side of campus. There are a lot of savings that come from operating a central plant over individual, local units. In general, central plant equipment is more efficient and consumes less energy. Another cost savings comes from the fact that there are fewer pieces of equipment to maintain, allowing for maintenance efforts to be more focused on less equipment. The current Central Chiller Plant serves approximately 700,000 ft2 of space on campus. The North Chiller Plant, once operational, is set to serve just over 400,000 ft2, with the potential to expand and serve close to 1,000,000 ft2.

  • Free Cooling – The idea behind free cooling is to utilize low ambient air temperatures to assist in the cooling process. In the North Chiller Plant, a heat exchanger is getting installed for just that purpose. Northern Plains Biostress has certain areas of the building that require year-round cooling. The heat exchanger in the NCP will circulate water to the outside, allowing the air to cool the water, and then send it back to NPB. This eliminates the need for mechanical cooling during the winter. Avera Health and Science Center and the South Dakota Art Museum also make use of this principle. Avera uses 100% outside air for its laboratories and the Art Museum requires cooling to protect the exhibits. Through some programming efforts, the water that gets cooled off from Avera gets sent over to the Art Museum to cool that building, and the heat gained from there preheats the air entering Avera.

  • Heat Recovery – Laboratories constructed on campus have incorporated heat recovery on the fume hood exhaust system. Heat recovery is a system which captures the heat that would have normally been lost in the building’s exhaust stream and recovers a portion of it to pre-heat the incoming air stream to the building. Heat recovery systems save tremendous amounts of energy on our cold South Dakota winter days. Heat recovery systems has been installed in Animal Resource Wing, Edgar S. McFadden Biostress Lab, Miller Wellness Center, McCrory Gardens Education and Visitor Center, Animal Science Complex, Avera Health and Science Center, Daktronics Engineering Hall Laboratory, Dairy Science, Jackrabbit Village bathrooms, Jackrabbit Grove bathrooms, Binnewies Hall bathrooms, Brown Hall bathrooms and Stanley J. Marshall Center pool.

  • High Efficiency Windows – As window replacement projects are accomplished or buildings are renovated, existing single pane windows are being replaced with more efficient double pane glass. Brown Hall, Mathews Hall, Wintrode Student Success and Opportunity Center, Dairy-Microbiology, Avera North, and Old Horticulture are some examples. All new construction incorporates high efficiency windows. Meadows North and Meadows South are the next buildings to have new windows installed.

  • Roof Insulation – Every summer SDSU replaces a portion of its buildings roofs that are at the end of their expected life. These roofing replacement projects incorporate additional insulation to reduce the heat lost from the building.

  • LEED Construction – SDSU is designing large capital improvement projects to meet LEED Silver certification requirements and incorporating many sustainable features. The Dykhouse Student-Athlete Center, Jackrabbit Village, Jackrabbit Grove, McCrory Gardens Visitor and Education Center, Alfred Dairy Science Hall, west wing of Daktronics Engineering Hall, Chicoine Architecture, Mathematics and Engineering Hall, and Sanford-Jackrabbit Athletic Complex are all constructed LEED facilities. Many other capital improvement projects will be designed to the LEED Silver energy efficiency standards and will incorporate sustainable features.

  • Energy Conservation Engineer – In 1999, Facilities and Services created a new position for an Energy Conservation Engineer. This individual is in charge of investing energy usage and proposing energy conservation projects throughout campus.