Energy Energy is the ability to do work. The word ‘work’ means transferring energy from one place to another. energy is neither destroyed nor created. It can only be changed. Thermal Electromagnetic Sound Types of Radiant Mechanical Energy Electrical Nuclear Chemical Any object in motion has mechanical energy. For example a ball flying through the air. Energy caused by the movement of electrons. Easily transported through power lines and converted into other forms of energy. • Comes from bonds between atoms in molecules • Chemical change = energy released • Examples: •Gasoline burning in a car •Food we eat Comes from reactions between atomic nuclei. Fission splits Fusion combines HUGE amounts of energy Includes energy from gamma rays, xrays, ultraviolet rays, visible light, infrared rays, microwave and radio bands. The Thermal energy is the internal kinetic energy and it considers the motion of every constitutive particle of the system (molecules, atoms, electrons, etc.). •Vibration of molecules in surrounding medium (usually air). Flows through empty space Examples: Sunlight Radio waves X-rays Renewable Non-renewable Renewable Energy Those sources of energy which are being produced continuously in nature and will never be exhausted, are called renewable sources of energy. Non-renewable Energy Those sources of energy which have been produced in nature over a very, very long time and cannot be quickly replaced when exhausted, are called non renewable sources of energy. Renewable sources Energy Solar energy Solar energy is the most readily available source of energy. It does not belong to anybody and is, therefore, free. It is also the most important of the nonconventional sources of energy because it is non-polluting and, therefore, helps in lessening the greenhouse effect. Biomass Biomass is a renewable energy resource derived from the carbonaceous waste of various human and natural activities. It is derived from numerous sources, including the by-products from the timber industry, agricultural crops, raw material from the forest, major parts of household waste and wood. Hydel Energy The energy in the flowing water can be used to produce electricity. Waves result from the interaction of the wind with the surface of the sea and represent a transfer of energy from the wind to the sea. Energy can be extracted from tides by creating a reservoir or basin behind a barrage and then passing tidal waters through turbines in the barrage to generate electricity. Geothermal Energy We live between two great sources of energy, the hot rocks beneath the surface of the earth and the sun in the sky. Our ancestors knew the value of geothermal energy; they bathed and cooked in hot springs. Today we have recognized that this resource has potential for much broader application. Wind Energy Wind energy is the kinetic energy associated with the movement of atmospheric air. It has been used for hundreds of years for sailing, grinding grain, and for irrigation. Wind energy systems convert this kinetic energy to more useful forms of power. Wind energy systems for irrigation and milling have been in use since ancient times and since the beginning of the 20th century it is being used to generate electric power. Windmills for water pumping have been installed in many countries particularly in the Coal Non- Renewable Energy Coal is the most abundant fossil fuel in the world. During the formation of coal, carbonaceous matter was first compressed into a spongy material called "peat," which is about 90% water. As the peat became more deeply buried, the increased pressure and temperature turned it into coal. OIL Crude oil or liquid petroleum, is a fossil fuel that is refined into many different energy products (e.g., gasoline, diesel fuel, jet fuel, heating oil). Oil forms underground in rock such as shale, which is rich in organic materials. Nuclear power In most electric power plants, water is heated and converted into steam, which drives a turbine-generator to produce electricity. Fossil-fueled power plants produce heat by burning coal, oil, or natural gas. In a nuclear power plant, the fission of uranium atoms in the reactor provides the heat to produce steam for generating electricity. Natural gas Natural gas production is often a byproduct of oil recovery, as the two commonly share underground reservoirs. Natural gas is a mixture of gases, the most common being methane (CH4). It also contains some ethane (C2H6), propane (C3H8), and butane (C4H10). Natural gas is usually not contaminated with sulfur and is therefore the cleanest burning fossil fuel.