Green Building and LEED Core Concepts Guide First Edition

Integrative design processes can bring these elements together to identify synergistic strategies.
The analysis of whole-building life-cycle costs is central to green building practice because it provides
a framework for understanding trade-offs between the first costs and the long-term operating
costs of HVAC and other energy-using systems. LEED encourages project teams to use simulation
models to quantitatively analyze the trade-offs and identify cost-effective energy-saving strategies.
This saves money over the life of the building, saves energy, and reduces greenhouse gas emissions
and other environmental impacts.
Assessments and Measurements
• Energy or greenhouse gas emissions per capita. A community's total greenhouse gas
emissions divided· by the total number of residents.
• Energy use intensity. Energy consumption div ided by the number of square feet in a building,
often expressed as British thermal units (Btus) per square foot or as kilowatt-hours of
electricity per square foot per year (kWh/sf/yr) .
• lighting power density. The installed lighting power per unit area.
• Measures of energy use. Typical primary measures of energy consumption associated with
buildings include kilowatt-hours of electricity, therms of natural gas, and gallons of liquid
fuel.
• Performance relative to benchmark. A comparison of a building system's performance with a
standard, such as EN ERGY STAR Portfolio Manager.
• Performance relative to code. A comparison of a building system's performance with a
baseline that is equiva lent to minimal compliance with an applicable energy code, such as
ASH RAE Standard 90 or California's Title 24.
ENERGY DEMAND
Saving energy begins with redu ci ng energy demand . Green buildings and neighborhoods
can reduce demand fo r energy by capturing natural, incidental encrgy, such as sunlight,
wind, and geothermal potential, and byusing integrated design processes to reduce loads. Examples
include the follOwing:
• Roads, infrastructure, and parce ls can be configured so that buildings minimize solar gain in
summer and maximize it in winter.
• Adjacent buildings can be designed to shade and insulate each other.
• Bui lding designs can incorporate passive strategies, such as mass and daylight, to red uce the
demand for artific ial lighting, heati ng, and cooling.
• Project teams can incorporate techno logies and processes that encourage occupants to
understand and reduce their individ ual and aggregate energy demand.
Taken together, demand reduction strategies provide the foundation for energy efficiency and the
effective use of renewable energy.
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Green Building and LEED Core Concepts Guide