How It's Generated
As we learned at a young age, electricity is generated when a turbine is spun
thus creating an electric current. There are a number of ways to fuel this
process, be it from burning coal, natural gas, harnessing the wind to rotate a
windmill's blades, nuclear power, or capturing heat from the earth itself
(geothermal energy). Regardless of how this process begins, once electricity is
generated it must be transported. Competitive suppliers use all these fuels and
others in providing reliable service to millions of consumers.
How It's Transmitted
Electricity must be generated and consumed at nearly the same time. To maintain
a reliable and secure electricity transmission grid, an intricate physical
balance must constantly be maintained between the amount of power that is
generated and the amount that is consumed since storage of electricity - like
other commodities such as airline seats and hotel rooms - is not a practical
reality at this time. The conveyance of electricity from a generating station to
end-use customers relies on complex transmission and distribution networks.
Transmission lines are generally of a higher voltage to carry more power across
longer distances. They can be thought of as a highway system for electricity. As
a matter of fact, transmission line towers often track along side actual
highways. Distribution lines are those often seen above or below city streets,
and carry power to individual consumers. Both sets of networks are critical to
delivery of power to consumers.
Where It's Transmitted
The continental United States is divided into three almost entirely separate
electricity "interconnections." These interconnections function on different
frequencies making transfers of power between them difficult. The Eastern
Interconnection generally includes everything east of the Rocky Mountains. The
Western Interconnection includes everything from the inter-mountain states to
the Pacific. The Electric Reliability Council of Texas (ERCOT) includes most of
Within these three interconnections differing regulatory and market structures
exist (discussed further below). The physics of generating electricity, however,
remains the same in all regions.