Energy Is the ability to do work or cause change.

There are several types of energy. All energy types can be classified as either kinetic energy or potential energy.

Kinetic energy is the energy of motion.

Potential energy is stored energy or the energy of position.

Energy

Thermal

Radiant

Sound

Motion -Mechanical

Electrical

Kinetic Potential

Chemical

StoredMechanical

Nuclear

Gravitation

Thermal energy is heat energy.

Radiant energy is solar and light energy that travels in electromagnetic waves.

Sound energy is energy that travels in longitudinal waves through substances.

Motion (Mechanical) – is the movement of objects from one place to another.

Electrical energy is the movement of electrical charges.

Chemical energy is the energy stored in the bonds of atoms and molecules. Fuels contain stored chemical energy that is released by burning the substance. When the substance is burned a chemical change takes place. This change is called combustion.

Nuclear energy is the energy stored in the nucleus of an atom.

Gravitational energy is the energy of position or place.

Stored Mechanical energy is energy stored in objects by the application of a force.

Energy Law IThe law of conservation of energy states that energy can not be created or destroyed; it only changes form.

Energy Law IIEnergy changes from a more useful form to a less useful form.

A scientific law is a general principle that is very well supported by evidence such as experimental results and observational data. Typically scientific laws are limited sets of rules that have a well documented history for successfully predicting the outcomes of experiments and observations. Scientific laws are generally considered to be true.

In science, a theory is a proposed description, explanation, or model of a set of natural phenomena, capable of predicting future occurrences or observations of the same kind, and capable of being tested through experiment or observation.

All food has chemical energy. Consumers eat and their bodies transform the chemical energy into thermal and motion energy.

Energy Transformations

chemical thermal motion

The same energy transformations take place when we put gasoline in cars.

An energy transformation is a change from one form of energy to another form of energy.

The toaster is powered with electricity. The toaster transforms or changes the electricity into heat and light.

electrical thermal light

The boy is applying a force by pulling back the slingshot. When he releases it, whatever he has in the slingshot will fly.

Stored mechanical motion

We use many different energy sources to do work for us. Energy sources are mostly classified into two groups—renewable and nonrenewable.

Energy sources are called renewable energy sources because they are replenished in a short time.

Energy sources are called nonrenewable because their supplies are limited.

Energy Sources

Sometimes a resource is classified as inexhaustible because the resource exists in such a large supply that it is considered to be limitless.

Solar Energy

Solar Cells (really called "photovoltaic" or "photoelectric" cells) convert light directly into electricity.

Solar energy is free and renewable or even inexhaustible (never run out).

Photovoltaic comes from the words photo meaning light. You are probably familiar with photovoltaic cells. Solar-powered toys and calculators use solar cells to convert sunlight into electricity.

Energy Conversions

Radiant (solar) electrical

Radiant (solar) electrical thermal

BiomassBiomass is any organic matter (anything that was once alive) that can be used as an energy source. Wood, crops, yard and animal waste are examples of biomass. Biomass gets it energy from the sun. Plants absorb sunlight in a process called photosynthesis. Biomass is a renewable energy source because we can grow more in a short period of time.

Burning is one way to release energy from biomass. By burning biomass, water can be heated to release steam which can turn a turbine that turns a generator that makes electricity. Biomass can also be converted into a gas or a liquid fuel that can be burned.

Hydroelectric powerHydropower (hydro means water) is energy that comes from the force of moving water. A hydro plant usually has 3 parts: a reservoir which is a lake that stores water, a dam with gates that can be opened or closed to control the flow of water, and a plant where electricity is produced. In the hydro plant, the gates in the dam open to allow the water to flow through a tube called a penstock. The flowing water turns the blade of a turbine.

The blades of the turbine turn a generator. A generator is a coil of wire with a spinning magnet inside. The generator produces electricity. Hydropower is a renewable resource.

Energy Transformations

gravitational Mechanical - Motion Electrical

Falling water Blades of the turbine turning Generator

Wind

Wind is air in motion. Wind is caused by the uneven heating of the Earth’s surface. Wind is a renewable resource.

The wind turns the propeller blades of the wind turbine. The turbine turns a generator that produces electricity.

Energy Transformations

Wind blowing turns the blades of the turbine

The turbine turns the generator.

Motion Electrical

Geothermal

Geothermal comes from the Greek words geo meaning earth and thermal meaning heat. Geothermal energy is energy from inside of the earth. Geothermal energy is a renewable and inexhaustible resource. Geothermal energy is a resource in volcanically active places.

HydrogenHydrogen is the energy resource of the future. Hydrogen gas is what fuels the sun in our solar system. Hydrogen atoms are fused together to form helium in the sun in a process called fusion. Hydrogen doesn’t exist on Earth by itself. It is combined with other elements in compounds like in water where two hydrogen atoms combine with one oxygen atom. NASA uses hydrogen to power the rockets that put space shuttle in orbit over Earth.

Right now it is expensive to produce hydrogen and new technologies need to be developed to make it more efficient to produce.

Fossil FuelsFossil fuels formed from the organic remains of prehistoric plants and animals. A solid fossil fuel is coal. A liquid fossil fuel is petroleum (oil) and a gas fossil fuel is natural gas. A form of natural gas that you might know is propane which is used to power barbeques. Fossil fuels are non-renewable.

Energy Transformations

Fossil Fuel is burned

The heat is used to heat water

The steam turns the blades of the turbine

The turbine turns the generator

Chemical thermal Motion Electrical

NuclearNuclear power is generated using uranium, which is a metal mined in different parts of the world. The reactor in a nuclear power plant uses Uranium rods as fuel, and the heat is generated by nuclear fission. Neutrons smash into the nucleus of the uranium atoms, which split roughly in half and release energy in the form of heat. The heat is used to make steam that turns the blades of turbines. The turbines power generators that create electricity. Uranium is a non-renewable resource.

Energy EfficiencyThe U.S. uses a lot of energy, nearly a million dollars worth each minute, 24 hours a day, 365 days a year. We consume almost ¼ of the world’s energy with less than 5% of the population. We use mostly non-renewable energy sources. With our reliance on energy to make our lives comfortable, productive, and enjoyable, we must find a way to use energy efficiently and conserve as much as we can.

Energy conservation is any behavior that results in the use of less energy.The 3 Rs of an energy-wise consumer are easy to put into practice. Reducing, reusing and recycling helps protect the environment and saves money, energy and natural resources.

ReduceBuying and using only what you need and also buying products that have less packaging.ReuseBuying products that can be used over and over instead of disposable items.RecycleRecycle materials that can be recycled like metals, glass, and paper. Buy products made from or packaged with recycled materials.

Another way to conserve energy is by insulating your home. Insulation is a layer of material that helps block the transfer of heat between the air inside and outside a building. Insulation is like a nice warm blanket for your house. Insulation can reduce heating and cooling needs by keeping the warm air in in the winter and keeping the warm air out in the summer.

Another way to use energy more efficiently is by changing from using incandescent light bulbs to compact fluorescent light bulbs. Incandescent light bulbs take more energy to produce the same amount of light as compact fluorescent bulbs.

Incandescent light bulb

Compact fluorescent light bulbs