- Energy: Traditional Approaches
- Energy: Environmental Challenges
- Energy: Sustainability Principles
- Energy: Sustainability Strategies
- Defining Energy Sources
- What is using our Energy: Energy Use & Breakdown
- Best Practices for Renewable Energy & Energy Efficiency
- Introdution to Greenhouse Gas Assessments
Cities and counties are part of larger energy systems in which energy originates beyond a community's borders and is controlled by parties over which a local jurisdiction has little control. Transportation fuels flow through pipeline systems that span whole regions of the country and are subject to decisions made by private companies and federal and state regulators. Electricity and natural gas are provided by utilities that may serve several states and governed by investors, customers, local authorities and federal and state regulators.
A municipal energy system is characterized by elements of energy supply and energy demand:
TRANSPORTATION FUEL SUPPLY
In the U.S. the transportation fuel supply is primarily petroleum based, a majority of which is imported. As evidenced by fuel supply disruptions and price volatility following Hurricane Katrina in 2005 and investment speculation in 2008, this system is sensitive to both natural and man-made disturbances. Alternative transportation fuels can be locally produced, refined and consumed, increasing resilience to supply disruptions and price volatility.
Coal, nuclear energy, and natural gas are among the most common fuels used to produce electricity. Most of the electricity in the United States is produced from coal. However, up to two-thirds of the energy inherent in coal is lost in the very process of transforming it into electricity. In addition, further energy is lost to "bleed off" due to inefficiencies in the electric grid.
Disturbances to the electric grid are typically more local in nature but, as the Northeast Blackout of 2003 demonstrated, outages can cascade to affect several states.
TRANSPORTATION ENERGY DEMAND
Transportation is a significant energy consumer within the purview of local governments. Unlike building and industry energy use which use a variety of primary fuels (coal, nuclear fuel and natural gas), the transportation sector is highly dependent on petroleum for its fuel supply.
BUILDINGS ENERGY DEMAND
Buildings are a significant consumer of energy in local communities, both in the embodied energy required in their construction and in the energy they consume once occupied and in operation. Local governments have significant opportunities to reduce the energy consumption of both new and existing buildings of both types via regulation, policy, incentives and education.
INDUSTRIAL BUILDINGS ENERGY DEMAND
Industrial processes are also significant energy consumers. Industries are classified separately because their energy use needs and patterns can be very different from residential and commercial building energy use patterns and requires different approaches and technology to achieve reductions in use.