Natural Resources Defense Council BUILDING GREEN FROM PRINCIPLE TO PRACTICE
Home Build Your Business Case Set Your Budget and Goals Adopt a Whole-Building Approach Apply Sustainable Building Strategies Capitalize on Your Achievement
SAVE ENERGY AND PROTECT THE
ATMOSPHERE

Energy-efficient design is one of the best opportunities you have for cutting costs and reducing your project's harmful environmental effects.
Windows and Daylighting

Incorporate daylight design elements such as clerestories, light shelves, skylights and high-performance windows. Increasing the amount of natural light in your building or workspace will reduce your electricity bill, as well as help boost employee productivity and satisfaction
Specify windows with a shading coefficient no higher than 0.4 on the south, east and west and a visible transmittance level above 0.6 to let sunlight in and keep excessive heat out. If you are building in a region with hot summers and cold winters, a U-value in the .25 to .35 range will provide adequate insulation against the heat and cold.
Tune your window specifications to your building's orientation. Shading coefficients are most important on southern, eastern and western exposures, while northern exposures should have high visible transmittance and low U-values.
Electricity Use

Site your building according to its heating and cooling needs. Adjusting a building's orientation by just a few degrees can have a big impact on the size of your heating and cooling system and your energy bill.
Specify lighting fixtures with a coefficient of utilization of at least 80 percent.
Make sure your fixtures and lamps are properly sized for use with one another. For example, T-5 lamps don't work as well in direct fixtures designed for T-8 lamps and may be too bright for some direct-lighting strategies.
Install occupancy sensors to control lighting, ventilation, air conditioning and heating in enclosed areas that are occupied intermittently, including offices.
Instead of using recessed fixtures to light a workspace, use a pendant strategy with an open top so light will hit the work surface and also reflect off the ceiling and walls into the task area.
Emphasize light-colored surfaces that reflect light and appear brighter.
Hire a lighting designer. A good lighting specialist will provide solutions that cut energy costs while creating a more pleasant and productive environment.
HVAC System

Hire an independent commissioning team early in the design process to check the design, installation, calibration and performance of your energy systems and help ensure you will meet your efficiency goals. Your design should include equipment to monitor water and energy performance over the entire life of the building.
Implement features such as low-e windows, increased insulation, task/ambient lighting and energy-efficient office equipment to reduce waste heat, which will allow you to downsize your HVAC system.
Consider staging multiple smaller HVAC chillers, rather than one large chiller. Compressors that run near capacity are most efficient. Variable speed drives can also help chillers operate more efficiently.
Specify oversized ducts that will deliver air at a lower speed and enable you to reduce the size and electricity consumption of your fans. An added benefit is a much quieter mechanical system.
Implement automated building controls for your HVAC system.
Office Equipment

Choose photocopiers, fax machines, printers, water coolers and other office equipment that carry the Energy Star label, an indication that they use an average of 50 percent less energy than standard models.
Ensure that the Energy Star "sleep mode" features are enabled on the equipment.
Make use of laptop computers, which use 50 percent to 90 percent less energy than standard desktop models.
Specify computer monitors with flat screens, which use half as much energy as CRT screens and offer sharper displays and less reflection.
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