Energy Efficiency: Goals

Goal 1. To reduce energy loads while maintaining a comfortable working and/or living environment .

1.1 Maximize thermal efficiency of building.

1.1.1 Select appropriate window placement.

1.1.2 Select appropriate window size and type to maximize daylighting and glare control while minimizing unwanted heat loss and heat gain. Recommended for our Minnesota climate by the U.S. Department of Energy are:[i]

  • Windows with a low U-factor (.35 or less) to minimize energy use.
  • Windows with the highest Solar Heat Gain Co-Efficient (SHGC) that can be found (0.30 – 0.60) to reduce heating. If cooling the building is a large concern, select windows with a SHGC less than 0.55.
  • Window glazing with a Visible Transmittance (VT) of .50 or more to maximize daylight.
  • Air Leakage at 0.30 or less (cfm/sq ft).

1.1.3 Use shading devices to reduce glare and overheating in warm summer months.

1.1.4 Optimize insulation to reduce energy consumption caused by heat losses or heat gains throughout the building envelope .

  • R-Value s that exceed local requirements :[ii]

Wall insulation > R-30.

Ceiling insulation > R-60.

1.1.5 Use thermal mass where appropriate to lessen interior temperature extremes.

1.1.6 Prevent thermal bridging.

  • Use insulating spacers to provide thermal isolation or a thermal break between the panels and purlins.

1.2 Install energy efficient appliances.

1.2.1 Use equipment with high efficiency motors and variable speed drives.

1.2.2 Use appliances that use little or no “leaking energy,” or energy that is still used while the appliance is not in use.

1.2.3 Use efficient appliances that meet the Energy Star criteria.

1.3 Raise awareness amongst the CSB/SJU community – students, faculty, staff, etc. – about energy efficiency and its importance.

1.3.1 Implement the topic of energy-efficiency into first-year orientation, the residence halls, and/or the college curriculum.

  • Turn lights off when leaving a room.
  • Shut-down computers at night.
  • Dress weather appropriately, avoiding the need to turn up thermostats.
  • Use daylight instead of electrical lighting whenever possible.

1.3.2 Limit refrigeration use in residence halls to no more than one per room.

1.3.3 Hold information sessions for faculty and staff on simple ways to reduce energy consumption during the work day (see 1.3.1 above).

 

Goal 2. Provide Heating, Ventilation, and Air Conditioning (HVAC) that is highly energy efficient while maintaining human comfort and environmental quality.

2.1 Implement energy savings strategies on current heating and cooling systems.

2.1.1 Use thermostats and “intelligent building controls” to control temperatures throughout the building according to the use per room/area of the building.

2.2 Implement renewable energy techniques for new systems.

2.2.1 Use Air-to-Air heat exchange which minimizes energy/heat loss from the building.

2.2.2 Use of any renewable energy type as listed in 4.1.1 below.

2.3 Provide an energy efficient ventilation system.

2.3.1 Design building to use natural ventilation during proper seasons.

2.3.2 If using Air-Conditioning, determine if cooling the whole building is necessary or if cooling particular rooms is sufficient. If cooling the whole building, an Energy Star air conditioner is recommended to be most efficient. If cooling particular rooms only, use room air conditioners which are also Energy Star approved.

2.3.3 Use furnaces or boilers which are Energy Star approved.

2.3.4 Do not use joist space or cavities for return air, use hard duct systems.

2.3.5 Minimize duct leakage , (i.e. no more than 10 percent of total system flow is allowed).

2.3.6 Size ducts according to room area and demand.

2.4 Design the ventilation system with the future in mind, (i.e. design the ventilation system so it can easily be added on to, or changed in case the use of the building changes and the ventilation requirements are different).

 

Goal 3. Provide energy efficient lighting while providing a comfortable working environment for individuals.

3.1 Use energy efficient lighting throughout the building.

3.1.1 Install Compact Fluorescent Lighting units in the building.

3.1.2 Incorporate Task Lighting methods throughout the building, encouraging lighting to fit the task at hand (i.e. a small bright lamp on a desk rather than lighting the whole room).

3.1.3 Install Lighting controls such as photo sensors, occupancy sensors, timers, and dimming switches.

3.2 Incorporate day lighting techniques into the construction of the building.

3.2.1 Select a site for the building where proper amounts of daylight can be attained (i.e. where sunlight is not blocked).

3.2.2 Design building to achieve equal distribution of natural light throughout day lit rooms. This would mean that you would want to design the building so that you are not receiving direct rays of sunlight on one area of the room while there is not any reaching other parts of the room.

3.2.4 Design the building with the capabilities of cooling the building in warmer seasons.

  • Allow for possible shading devices.
  • Natural ventilation to cool the room while still allowing daylighting techniques for lighting the room.

 

Goal 4. To use energy sources with low environmental impacts and to reduce dependence on fossil fuel s.

4.1 Supply at least 20 percent of the building’s net annual energy load with renewable energy systems.

4.1.1 Incorporate passive solar systems – heating, cooling, and daylighting – into a structure.

  • Choose a location with good solar exposure.
  • The optimal wall to window ratio is 25 to 35 percent.[iii]
  • Place large windows on the south side.
  • Use appropriate thermal mass.

4.2 Consider active solar systems.

  • Photovoltaic.

4.3 Consider incorporating wind energy.

4.4 Fuel cells are an up-and-coming alternative energy source. Look for them to be more accessible and affordable in years to come.

4.5 Purchase green power.

 

[i] Efficient Window Collaborative. “Fact Sheet: Energy-Efficient Windows in Minnesota,” 2002, (16 April 2004).

[ii] Chiras, Daniel, D. The Natural House: A Complete Guide to Healthy, Energy-Efficient, Environmental Homes. (Vermont: Chelsea Green Publishing, 2000), 372.

[iii] U.S Department of Energy. “Solar,” 2004. (27 April 2004).