How would you define energy? Energy: a force of power that makes things happen

What sources of energy were mentioned in the Magic School Bus? – Electrical – Wind – Water – Solar Other than electrical energy, what do all of the other energy sources have in common? – Natural, not man-made – Cannot run out

Renewable Energy What do we call sources of energy that will never run out (are always available)? – Renewable resources Renewable resources come from nature – They can be “harnessed” (captured) for energy

Renewable Resource #1: Water Water has a lot of power when in motion! The energy from moving water can create electricity: 1.A hydroelectric dam - It captures energy from the movement of a river. Dam operators control the flow of water and the amount of electricity produced. Dams create reservoirs (large bodies of calm water) behind them, which can be used for recreation, wildlife sanctuaries, and sources of drinking water. 1.Flowing water turns a water wheel or turbine. 2.A generator attached to the turbine produces electricity.

2.Wave power - captures energy from waves on the surface of the ocean using a special buoy or other floating device. 3.Tidal power – It captures the energy of flowing waters with the help of turbines as tides rush in and out of coastal areas. Renewable Resource #1: Water

Disadvantages of using Hydropower 1.Hydropower can disrupt aquatic ecosystems (whether it be ocean ecosystem or lake/river ecosystem) 2.Hydroelectric power is expensive to build 3.The flow and movement of water is sometimes unreliable

A small number of countries, including Norway, Canada, Brazil, New Zealand, Paraguay, Venezuela and Switzerland, produce the majority of their electricity through hydropower. Did you know that Niagara Falls is the biggest electricity producer in the New York State, generating enough electricity to light 24 million 100–watt bulbs at once! Hydropower is the leading renewable energy source used to generate electricity in the United States.

Renewable Resource #2: Wind 1.Windmills – Windmills have been used for thousands of years in farms to grind grain and pump water 2.Wind turbines – A group of modern windmills, called, turbines, are placed together on wind farms to produce electricity As the wind blows over the blades of a wind turbine, it causes the blades to lift and rotate. The rotating blades turn a shaft that is connected to a generator. The generator creates electricity as it turns.

Disadvantages of Using Wind Power Wind in unpredictable Good locations for wind power are often far from where electricity is needed Wind turbines can be noisy

The United States and China are the largest producers of wind power in the world In the United States, wind energy now produces enough electricity to power more than 9 million homes. As of 2009, around 80 different countries use wind power to generate electricity commercially

Renewable resource #3: Sun/Solar Light and heat from the sun creates solar energy 1.Photovoltaic cells – Convert sunlight into electricity 1.Sunlight hits the surface of the photovoltaic cell. 2.A material called a semi-conductor converts the light into electricity.

Renewable resource #3: Sun/Solar 2.Solar Thermal Technology – Convert sunlight into electricity 1.Mirrors or reflectors concentrate the sun's rays to heat a special kind of liquid. 2.The heat from this liquid boils water to create steam. 3.Steam spins a turbine that is connected to a generator, which creates electricity. 4.The steam cools and condenses back to water, which is recycled, reheated, and converted into steam again.

Renewable resource #3: Sun/Solar 3.Passive solar heating – Letting sun shine through windows and naturally heating up rooms

Here’s Something Cool! Let’s learn about solar cooking: