Energy Efficiency

Energy efficiency addresses the demand for energy and the types of sources utilized for energy production in order to reduce air pollution and its impacts on environment and human health.

The Importance of Energy Efficiency and Renewable Energy

Did you know?

  • In the United States, buildings use 37% of all energy and 68% of all electricity.1
  • The EPA estimates that particulate matter, a common air pollutant from power plants, kills 20,000 people and hospitalizes many more each year.2
  • Due to air pollution, often resulting from building energy use, the average visual range has decreased from 90 miles to 15-25 miles in eastern U.S. national parks and from 140 miles to 35-90 miles in the western parks.3
  • Renewable energy sources make up just 1% of conventional electricity.4
  • Over the past decade, power produced by solar photovoltaics has grown over 700% and power produced using wind energy has grown by 900%.5
  • Power plants – the main source of heat and electricity for buildings – are responsible for 69% of the nation’s sulfur dioxide emissions, 22% of the nitrogen oxides, 33% of stationary mercury and 39% of the carbon dioxide. 6
  • A 500-megawatt coal-fired power plant produces an average of 318,000 tons of waste each year, and 75% of it is landfilled. 7

Defining Green Building Choices in This Category


  • High-efficiency, ENERGY STAR-certified heating and cooling units have been selected.
  • Renewable energy systems – such as solar photovoltaics, solar thermal, and ground source heat pumps – have been considered and/or installed.
  • Relevant appliances are ENERGY STAR-certified.
  • Lighting fixtures using energy-inefficient incandescent bulbs are replaced with more efficient compact fluorescents and LED lights.
  • Consideration has been given to floor plan and window location to provide for views to the outside and abundant daylighting.
  • Insulation has a high R-value to prevent air seepage. 
  • Programmable thermostats, occupancy sensors and photosensors are used to reduce energy use.
  • The home uses green energy offsets – such as those from solar, wind and landfill methane sources.
  • Windows are ENERGY STAR-certified.

Energy Efficiency and Renewable Energy Features in the GreenHome

The GreenHome will be carbon neutral in operations. This means that energy use in the home will not be responsible for any carbon dioxide emissions. This is a high bar, but we believe we can achieve it by maximizing energy efficiency and reducing demand through the use of ground source heat pumps, spray-foam blown-in insulation, a sealed crawl space, rigid foam insulation, ENERGY STAR-certified windows and a roof with more than three times the solar reflectance of conventional roofs. In addition, an under-roof solar thermal system, a 10-kilowatt solar photovoltaic array, and a desuperheater on the ground source heat system for hot water heating provide substantial sources of renewable energy. Renewable energy credits will be purchased to offset any remaining energy use from conventional fossil fuel or nuclear supplied energy sources.

The GreenHome showcases the following energy-efficient features:

  • Insulation – Spray and Rigid Foam
  • Advanced Framing
  • Reflective Roofing
  • Foundation
  • Sealed Attic and Crawlspace
  • Daylighting – Windows and Translucent Roof
  • Window Shading
  • Thermal Massing
  • Ground Source Heat Pump
  • Energy Recovery Ventilator (ERV)
  • Solar Thermal Hot Water
  • Radiant Flooring
  • Hot Water Heat Exchange
  • Photovoltaics
  • Renewable Energy Credits
  • ENERGY STAR Certification
  • Lighting
  • Highly Insulated Doors
  • High Performance Ventilation Fans
  • Passive Design
  • Bio-Diesel Fuel