KidWind Project | www.kidwind.org Electric Power Generation Electricity is an essential part of modern life. In our homes we use it for lighting, running appliances and electronics, and often for heating and cooling. Most consumers don’t think much about their electricity until a power outage, or when they get a high utility bill. Fortunately in the United States, power outages are relatively infrequent and short in duration mainly because we have one of the most advanced, reliable, and well-maintained electricity generation, transmission, and distribution systems in the world. We plug in an appliance or turn on a switch without giving it a second thought. To ensure that continuous flow of electricity is there to meet our needs, electric power producers operate several types of large generators. KidWind Project | www.kidwind.org

KidWind Project | www.kidwind.org Why Isn’t Electricity Listed In This Table? Electricity is the flow of electrical power or charge. It is one of our most widely used forms of energy. Even though approximately 40% of the energy used in the United States in 2006 was electricity, it is not considered a primary source of energy. Ask students why they think electricity is not considered a primary source of energy. Have them discuss this question before going on to slide three. KidWind Project | www.kidwind.org

KidWind Project | www.kidwind.org Electricity Is An Energy Carrier Current electricity does not exist in nature. It must be produced (generated) by using a primary source of energy such as a fossil fuel, uranium, wind or solar energy. Therefore, it is called an energy carrier, also referred to as a secondary energy source. Energy carriers are primary sources of energy that are transformed through an energy conversion process to more convenient sources of energy that can be used directly by society. Examples include electricity, refined fuels (gasoline, propane, heating oil, ethanol, etc.) and hydrogen. KidWind Project | www.kidwind.org

Common Energy Carriers Electricity is one of the most common energy carriers, being transformed from various primary energy sources such as coal, uranium, natural gas, geothermal, and wind. Primary energy sources cannot be produced, they must be available in nature This table lists all the readily available primary energy sources. It also shows any associated energy carriers that come predominantly from that energy source. While the energy carriers in the table above come primarily from a specific energy source, there are a couple of carriers that are quite general and can be produced from any energy source. Electricity is the only exception to the source/carrier separation. It is a pure carrier except in the static form that exists in our atmosphere. We cannot currently effectively extract this resource (static electricity), so electricity falls into the energy carrier category. Electricity is highly used in the U.S. as an energy carrier as it transports well over long distances.

Electric Power Generation Plant A power generation plant is a facility designed to produce electric current from a primary source of energy. KidWind Project | www.kidwind.org

How Does Electricity Get To Your Home? KidWind Project | www.kidwind.org

Step 1- Power Plant and Generator Electricity is made at a power plant by huge generators. Most power plants use coal, but some use natural gas, water or even wind. KidWind Project | www.kidwind.org

Step 2 – Step-Up Transformer The current is sent through transformers to increase the voltage to push the power long distances.  KidWind Project | www.kidwind.org

Step 3 – High Voltage Transmission Lines The electrical charge goes through high-voltage transmission lines that stretch across the country.  KidWind Project | www.kidwind.org

Step 5 – Step-Down Substation It reaches a substation, where the voltage is lowered so it can be sent on smaller power lines. KidWind Project | www.kidwind.org

Step 6 – Distribution Lines It travels through distribution lines to your neighborhood, where smaller pole-top transformers reduce the voltage again to take the power safe to use in our homes. KidWind Project | www.kidwind.org

KidWind Project | www.kidwind.org Step 7: Service Drop It connects to your house through the service drop and passes through a meter that measures how much our family uses.  KidWind Project | www.kidwind.org

KidWind Project | www.kidwind.org Step 8 – Service Panel The electricity goes to the service panel in your basement or garage, where breakers or fuses protect the wires inside your house from being overloaded.  KidWind Project | www.kidwind.org

Step 9 – Home Wiring, Outlets and Switches The electricity travels through wires inside the walls to the outlets and switches all over your house.  KidWind Project | www.kidwind.org

KidWind Project | www.kidwind.org Electricity Is An Energy Carrier Use this slide to review the steps outlining how electricity gets to you home. KidWind Project | www.kidwind.org

KidWind Project | www.kidwind.org Does All of Your Electricity Come from Your Local Power Plant? No. Today there are more than 9,000 electric utility companies and other generating units all over America that produce and distribute more than one million megawatts of electricity to homes, businesses, and other energy users. To get that electricity to its users, there are more than 300,000 miles of high-voltage electric transmission lines across the U.S. Each local power company's transmission lines are linked regional networks that share electricity. These power plants are connected to regional The U.S. electric grid is a complex network of independently owned and operated power plants and transmission lines. KidWind Project | www.kidwind.org

THERMAL (STEAM TURBINE) ELECTRICAL POWER PLANTS Fossil Fuel Geothermal Most of the electricity in the United States is produced in thermal power plants using steam turbines. These steam turbines use coal, natural gas, petroleum, and uranium as a fuel. The turbine converts the kinetic energy of a moving fluid (liquid or gas) to mechanical energy. A nuclear power plant is basically a steam power plant that is fueled by a radioactive element, like uranium. The fuel is placed in a reactor and the individual atoms are allowed to split apart. The splitting process, known as fission, releases great amounts of energy. This energy is used to heat water until it turns to steam. From here, the mechanics of a steam power plant take over. The steam pushes on turbines, which force coils of wire to interact with a magnetic field. This generates an electric current. Nuclear KidWind Project | www.kidwind.org

Transforming Energy – Thermal Power Plant You need to click this slide 7 times for all of the images graphic to show up. This is a simple example of how a thermal power plant transforms an energy source into electricity. Thermal energy is transformed from some other form of energy - chemical (coal, natural gas, petroleum or biomass) or nuclear (uranium) The thermal energy is transmitted into water creating steam. As the steam expands, the thermal energy is transformed into mechanical energy by pushing against the blades of a turbine. The mechanical energy from the turbine is transmitted through a shaft and used to spin magnets within a coil of wires (a generator.) The movement of magnets past a coil of wire induces an electrical current in the wires, transforming mechanical energy into electrical energy. The electrical energy is transmitted through wires to the customer.

Hydro and Wind Turbines Hydroelectric plants and wind turbines convert kinetic energy of falling water or wind into mechanical energy. Then a generator converts the mechanical energy from the turbine into electrical energy. KidWind Project | www.kidwind.org

KidWind Project | www.kidwind.org Solar Power Solar panels, containing photovoltaic cells, convert the radiant energy from the sun into electrical energy. KidWind Project | www.kidwind.org

KidWind Project | www.kidwind.org Coal is the most common fuel for generating electricity in the U.S. In 2009, 46% of the country’s nearly 4 trillion kilowatthours of electricity used coal as its source of energy. Natural gas, in addition to being burned to heat water for steam, can also be burned to produce hot combustion gases that pass directly through a turbine, spinning the turbine’s blades to generate electricity. Gas turbines are commonly used when electricity usage is in high demand. In 2010, 24% of the nation’s electricity was fueled by natural gas.Less than 10% is generated by renewable sources of energy. KidWind Project | www.kidwind.org

KidWind Project | www.kidwind.org Electricity Consumption By Economic Sector 2010 Electricity Consumption Totaled Nearly 3,884 billion kilowatthours (kWh) in 2010. U.S. electricity use in 2010 was more than 13 times greater than electricity use in 1950. The share of electricity use by major consuming sectors: Residential — 39% Commercial — 35% Industrial — 26% (includes "direct use") Transportation —>1%. Only a small percentage of electricity is used in the transportation sector, mostly for trains and plug-in electric cars. Direct use is electricity generated mainly by manufacturing that is used by the facilities . U.S. electricity demand fluctuates in the short term in response to business cycles, weather conditions, and prices. Over the long term, electricity consumption increases. However, electricity demand growth has slowed progressively by decade since 1950, from 9% per year in the 1950s to less than 2.5% per year in the 1990s. From 2000 to 2009, increases in electricity demand averaged 0.5% per year. Demand growth is projected to continue at about 1% per year through 2035. U.S. Energy Information Administration / Annual Energy Review 2009 KidWind Project | www.kidwind.org

KidWind Project | www.kidwind.org Most of the electricity used in the residential sector is for air conditioning, refrigerators, space and water heating, lighting, and powering appliances and equipment. Electricity demand fluctuates in the short term in response to business cycles, weather conditions, and prices. Over the long term, electricity consumption increases. However, electricity demand growth has slowed progressively by decade since 1950, from 9% per year in the 1950s to less than 2.5% per year in the 1990s. From 2000 to 2009, increases in electricity demand averaged 0.5% per year. Demand growth is projected to continue at about 1% per year through 2035. KidWind Project | www.kidwind.org