Saturday, June 21, 2008

Chemical Energy

The chemical energy is the biggest source of energy employed by the man. The energy generated because of the associations of the atoms in the molecules and various kinds of aggregates of the matter results in the formation of chemical energy. It can be defined as the work done by the electric forces at the time of the re-arrangement of the electric charges, protons and electrons, during the course of aggregation.

When the chemical energy of a structure decreases at the time of a chemical retort, the difference is then transferred to surrounding areas often in the form light or heat; whereas on the other hand, when the chemical energy increases because of chemical reaction, the variation is then supplied by the surroundings normally in the form of light or heat. Paradoxically, the majority of the electricity generated globally comes from chemical energy. Especially the burning of the oil, coal and gas generates chemical energy which results in electricity. The most suitable form to store the energy is the chemical energy. The food we have, pooled with the breathing oxygen, accumulate the energy which our body extracts and change it to thermal energy and mechanical energy. The batteries are yet another example of how the chemical energy is stored, that is later regained as the electrical energy.

The relationships which we anticipate from all the forms of energy are similar to the chemical energy also. It is very important for the humans to control, master and generate the chemical energy in order to survive on the earth.

Friday, June 20, 2008

Types Of Energy

Energy is a scalar physical quantity which is defined as the ability to do work. When a force applied on an object moves the object, work is said to be done and energy is spent. There are various types of energy present in the universe: kinetic energy, light energy, chemical energy, sound energy, electrical energy, mechanical energy, heat energy, elastic energy and gravitational energy.

The various types of energy are classified on the basis of the way the energy is apparent, the origin of energy and the way energy is carried. The total energy in a system doesn’t change with time but its frame of reference determines the value of different types of energy. For example, a passenger seating in a moving airplane does not have any kinetic energy relative to the plane, but has non zero kinetic energy comparative to earth. The various types of energy are interchangeable from one form to another. This is in accordance to the law of conversation of energy for an isolated system. The various types of energy can be transformed into matter and vice versa. The different types of energy are either renewable or non renewable. Renewable energy is that which can be renewed for future use. Non renewable energy can be just used once.

Energy is required to do all forms of activity. Every organism present on this planet depends on an external source to derive some type of energy to be able to do work. For example, plants need sunlight, animals need some form of chemical energy.

Renewable Energy Sources

Renewable energy sources are natural resources such as wind, sunlight, tides, rain and geothermal energy. Renewable energy is replenished naturally unlike the fossil energy sources such as oil, coal and natural gas which are limited. The various renewable energy technologies are: wind power, solar power, hydroelectricity, bio fuels and biomass.

The potential of renewable energy sources is very vast, surpassing all other available sources. The renewable energy technology is sometimes criticized for being unsightly or too intermittent. But the market is growing on for various renewable energy sources. Wind power has been growing at a rate of 30 percent and has a worldwide capacity of more than 100 GW. Solar power stations operate in various parts of United States and Spain, and the largest of these in installed in the Mojave Desert having a capacity of 354 MW SEGS. High oil prices coupled with the climatic concerns are motivating increasing use of renewable energy sources. Governments worldwide are taking strict measures to popularize the use of renewable energy sources. The European Union leaders have reached on an agreement in March 2007 to ensure that by 2020, 20 percent of the energy produced should come from renewable energy sources. These measures are been taken to reduce the global warming caused by the emission of carbon dioxide from the fossil fuels into the atmosphere.

Renewable energy sources are particularly suitable for developing countries. The transmission and circulation of fossil fuels energy in remote and rural areas can be a demanding task as well as very costly. Renewable energy produced locally provides with a vital option.

Hydroelectric Energy

Hydroelectric energy is the most widely used form of renewable source of energy. Unlike the fossil fuels, it does not produce any waste product or release carbon dioxide into the atmosphere. Hydroelectric energy accounts for about 19 percent of the world electricity.

Water has been long used to produce energy. Hydroelectric energy is generated by the rotation of water turbines at a very high speed by the fast flowing water that has been released from dams in mountainous regions. In this whole process, the energy of running water is first converted into mechanical energy of the turbines which is then converted into electric energy. Places with steep mountains and high rainfalls are ideal for producing hydroelectric energy. The hydroelectric energy plants require large dams to be built across rivers which are very expensive. But after that, it has a very low operating cost. Also since the flow of water can be controlled, hydroelectric energy can be obtained whenever required. Using hydroelectric energy plants also has several disadvantages. Building of dams can cause the blockage of fish passage to the ocean or to the spawning ground. Hydroelectric energy plants can also have an effect on the quality of water by reducing the dissolved oxygen content in the water.

The use of water in order to produce hydroelectric energy is an attractive substitute to the non renewable fossil fuels. But the technology has still some work to do in overcoming obstacles related to building costs, space requirements, displacement of people and the environmental impacts.

Energy Star

Energy Star is a global standard for the energy proficient end user products. It was first created by the United States Environment Protection Agency (EPA) in 1992 to promote energy proficient products in an attempt to minimize the energy usage and the greenhouse effect by industrial power plants. Over the years, this program has been adopted by several countries like Australia, Japan, Canada, Taiwan, New Zealand and the European Union.

The energy star program was developed by the US EPA’s John S. Hoffman and implemented by Brian Johnson and Cathy Zoi. Energy star help reduce the energy consumption of a product by either automatically switching the appliance into a dormant mode or/and limiting the power usage of a product in a standby mode. Initially energy star started with markers for various computer products. In 1995 the program was expanded to include residential cooling and heating systems and newly built homes. As of 2006, at least 40,000 energy star labeled products were available that comprised a wide range of items such as kitchen appliances, computer products, buildings, office equipment and more. Homes that have been qualified by energy star are at least 15 percent more energy proficient than the homes that were built in accordance with the 2004 International Residential Code (IRC). The energy star program has facilitated the use of fluorescent lighting, LED traffic lights, power management systems and low reserve energy use. In 2006 alone, the EPA has estimated to have saved about $14 billion in energy expenses.

The energy star program was the first step by the US government in order to increase the usage of energy efficient products and had produced overwhelming results in the saving of energy expenses.

Energy Resources

Energy resources are subdivided into two groups: renewable resource of energy and non renewable resource of energy. Renewable resources are those that can be replenished in a short period of time, while non renewable energy resources are those which we are constantly using up and cannot create in a short span of time.

Renewable energy resources include the solar energy, wind energy, wave and tidal energy, geothermal energy, biomass and hydropower. These are clean energy resources and does not produce waste products or release carbon dioxide into the atmosphere. For instance, the solar energy is the energy from the sun which can be used to produce electricity and heat. Similarly wind and thermal energy from inside the earth can be used to produce different types of energy. However most of our energy demand is met by energy produced from non renewable energy resources such as the fossil fuels like coal, oil, natural gas. These energy resources have been formed over million of years by the action of the pressure from soil and rock on the remains of dead animals and plants and the heat from the Earth’s core. These energy resources release waste product and carbon dioxide into the atmosphere.

Energy is required to perform almost all the tasks. The non renewable energy resources are fast depleting. These energy resources should be used smartly and the government must encourage the use of alternative renewable energy resources. It provides a great alternative to the energy requirements of the people and is also environment friendly.