Renewable Energy
There are
many forms of renewable energy . Most of these renewable energies depend in one way or another
on sunlight. Wind and hydroelectric power are the direct result of differential
heating of the Earth's surface which leads to air moving about (wind) and
precipitation forming as the air is lifted. Solar energy is the direct
conversion of sunlight using panels or collectors. Biomass energy is stored
sunlight contained in plants. Other renewable energies that do not depend on
sunlight
are geothermal energy, which is a result of radioactive decay in the crust combined with the original heat of accreting the Earth, and tidal energy, which is a conversion of gravitational energy.
are geothermal energy, which is a result of radioactive decay in the crust combined with the original heat of accreting the Earth, and tidal energy, which is a conversion of gravitational energy.
Solar.
This form of
energy relies on the nuclear fusion power from the core of the Sun. This energy
can be collected and converted in a few different ways. The range is from solar
water heating with solar collectors or attic cooling with solar attic fans for
domestic use to the complex technologies of direct conversion of sunlight to
electrical energy using mirrors and boilers or photovoltaic cells.
Unfortunately these are currently insufficient to fully power our modern
society.
Wind
Power. The movement of the atmosphere is driven by differences of
temperature at the Earth's surface due to varying temperatures of the Earth's
surface when lit by sunlight. Wind energy can be used to pump water or generate
electricity, but requires extensive areal coverage to produce significant
amounts of energy.
Hydroelectric energy. This form uses the gravitational
potential of elevated water that was lifted from the oceans by sunlight. It is
not strictly speaking renewable since all reservoirs eventually fill up and
require very expensive excavation to become useful again. At this time, most of
the available locations for hydroelectric dams are already used in the
developed world.
Biomass is the term for energy from plants. Energy in this form is
very commonly used throughout the world. Unfortunately the most popular is the
burning of trees for cooking and warmth. This process releases copious amounts
of carbon dioxide gases into the atmosphere and is a major contributor to
unhealthy air in many areas. Some of the more modern forms of biomass energy
are methane generation and production of alcohol for automobile fuel and
fueling electric power plants.
Hydrogen and fuel cells. These are also not strictly
renewable energy resources but are very abundant in availability and are very
low in pollution when utilized. Hydrogen can be burned as a fuel, typically in
a vehicle, with only water as the combustion product. This clean burning fuel
can mean a significant reduction of pollution in cities. Or the hydrogen can be
used in fuel cells, which are similar to batteries, to power an electric motor.
In either case significant production of hydrogen requires abundant power. Due
to the need for energy to produce the initial hydrogen gas, the result is the
relocation of pollution from the cities to the power plants. There are several
promising methods to produce hydrogen, such as solar power, that may alter this
picture drastically.
Geothermal power. Energy left over from the original
accretion of the planet and augmented by heat from radioactive decay seeps out
slowly everywhere, everyday. In certain areas the geothermal gradient (increase
in temperature with depth) is high enough to exploit to generate electricity.
This possibility is limited to a few locations on Earth and many technical
problems exist that limit its utility. Another form of geothermal energy is
Earth energy, a result of the heat storage in the Earth's surface. Soil
everywhere tends to stay at a relatively constant temperature, the yearly average,
and can be used with heat pumps to heat a building in winter and cool a
building in summer. This form of energy can lessen the need for other power to
maintain comfortable temperatures in buildings, but cannot be used to produce
electricity.
Other
forms of energy. Energy from tides, the oceans and hot hydrogen fusion are
other forms that can be used to generate electricity. Each of these is
discussed in some detail with the final result being that each suffers from one
or another significant drawback and cannot be relied upon at this time to solve
the upcoming energy crunch.
Can A
Country Achieve 100% Renewable Energy?
If you think
100% renewable energy will never happen, think again. Several countries have
adopted ambitious plan to obtain their power from renewable energy. These
countries are not only accelerating RE installations but are also integrating
RE into their existing infrastructure to reach a 100% RE mix. Read our article..
What are
renewable energy sources? Solar power can be used directly for heating and producing
electricity or indirectly via biomass, wind, ocean thermal, and hydroelectric
power. Energy from the gravititational field can be harnessed by tidal power;
and the internal heat of the Earth can be tapped geothermally.
These tools
and more can help make the transition from non-renewable to renewable
and environmentally friendly energy. However, none of these is sufficiently
developed or abundant enough to substitute for fossil fuels use. Every one of
these power sources (with the exception of hydroelectric) has low environmental
costs, and combined have the potential to be important in avoiding a monumental
crisis when the fossil fuel crunch hits. These energy sources are often
non-centralized, leading to greater consumer control and involvement.
However,
currently each of these energy forms is significantly more expensive than fossil fuels,
which will lead to economic dislocations and hardship if they become the only
power source for the future
Climate
change and the need to manage diminishing fossil fuel reserves are, today, two
of the biggest challenges facing the planet.
In order to secure the future for ourselves and generations to follow, it is widely accepted that we must act now to reduce energy consumption and substantially cut greenhouse gases, such as carbon dioxide. World leaders have resolved to tackle global warming by signing the Kyoto Protocol, an international treaty committing signatory countries to reduce their emissions of carbon dioxide and five other greenhouse gases from 1990 levels.
The UK is a signatory of the Kyoto Protocol and is actively involved in measures to meet our commitment of a 12.5 per cent cut in greenhouse gas emissions by the period 2008-12. But there is no single solution for the UK or the 155 other countries also aiming to reduce their emissions. The UK response to this challenge is a suite of policies that tackle the emissions problem across sectors, and in a variety of different ways. Energy efficiency and renewable energy
In order to secure the future for ourselves and generations to follow, it is widely accepted that we must act now to reduce energy consumption and substantially cut greenhouse gases, such as carbon dioxide. World leaders have resolved to tackle global warming by signing the Kyoto Protocol, an international treaty committing signatory countries to reduce their emissions of carbon dioxide and five other greenhouse gases from 1990 levels.
The UK is a signatory of the Kyoto Protocol and is actively involved in measures to meet our commitment of a 12.5 per cent cut in greenhouse gas emissions by the period 2008-12. But there is no single solution for the UK or the 155 other countries also aiming to reduce their emissions. The UK response to this challenge is a suite of policies that tackle the emissions problem across sectors, and in a variety of different ways. Energy efficiency and renewable energy
Why is renewable energy important?
Workers install equipment for an
ocean thermal energy conversion experiment in 1994 at Hawaii's Natural Energy
Laboratory. Credit: A. Resnick, Makai Ocean Engineering, Inc.
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.
.
No comments:
Post a Comment