The United States (and most of the rest of the industrialized
world) currently relies heavily on coal, oil, and natural gas
for its energy. Fossil fuels are nonrenewable, that is, they
draw on finite resources that will eventually dwindle, becoming
too expensive or too environmentally damaging to retrieve. In
contrast, renewable energy resources—such as wind and solar
energy—are constantly replenished and will never run out.
Most renewable energy comes either directly
or indirectly from the sun. Sunlight, or
solar energy, can be used directly for heating and lighting
homes and other buildings, for generating electricity, and
for hot water heating, solar cooling, and a variety of commercial
and industrial uses.
The sun's heat also drives the winds,
whose energy is captured with wind turbines. Then, the winds
and the sun's heat cause water to evaporate. When this water
vapor turns into rain or snow and flows downhill into rivers
or streams, its energy can be captured using hydroelectric
power.
Along with the rain and snow, sunlight causes
plants to grow. The organic matter that makes
up those plants is known as biomass. Biomass can be used to
produce electricity, transportation fuels, or chemicals. The
use of biomass for any of these purposes is called biomass
energy.
Hydrogen also can be found
in many organic compounds, as well as water. It's the most
abundant element on the Earth. But it doesn't occur naturally
as a gas. It's always combined with other elements, such as
with oxygen to make water. Once separated from another element,
hydrogen can be burned as a fuel or converted into electricity.
Not all renewable energy resources come from
the sun. Geothermal energy taps the Earth's
internal heat for a variety of uses, including electric power
production, and the heating and cooling of buildings. And
the energy of the ocean's tides comes from the gravitational
pull of the moon and the sun upon the Earth.
In
fact, ocean energy comes from a number of
sources. In addition to tidal energy, there's the energy of
the ocean's waves, which are driven by both the tides and
the winds. The sun also warms the surface of the ocean more
than the ocean depths, creating a temperature difference that
can be used as an energy source. All these forms of ocean
energy can be used to produce electricity.
Why
is renewable energy important?
Renewable energy is important because of the benefits it provides.
The key benefits are:
Environmental
benefits
Renewable energy technologies are clean sources of energy
that have a much lower environmental impact than conventional
energy technologies.
Energy
for our children's children's children
Renewable energy will not run out. Ever. Other sources of
energy are finite and will some day be depleted.
Jobs
and the economy
Most renewable energy investments are spent on materials and
workmanship to build and maintain the facilities, rather than
on costly energy imports. Renewable energy investments are
usually spent within the United States, frequently in the
same state, and often in the same town. This means your energy
dollars stay home to create jobs and fuel local economies,
rather than going overseas.
Meanwhile,
renewable energy technologies developed and built in the United
States are being sold overseas, providing a boost to the U.S.
trade deficit.
Energy
security
After the oil supply disruptions of the early 1970s, our nation
has increased its dependence on foreign oil supplies instead
of decreasing it. This increased dependence impacts more than
just our national energy policy.
