For thousands of years, people have been harnessing wind energy to do work—from traveling around the world on sailing ships to milling grain using windmills. Today, wind is becoming more common as a renewable energy source through the use of wind turbines.

Wind turbines have four basic parts–a tower, turbine blades, a gear box, and a generator–that function together to convert kinetic energy from the wind into electrical energy. As the blades turn, they cause the gear box to turn, via a shaft. The turning gear box causes the generator to turn via a second shaft. The turning of the generator generates electricity.

The amount of electrical power that can be generated by a wind turbine is affected by many variables. In this experiment, you will explore variables that affect how a turbine turns. You will then use data-collection equipment to quantitatively investigate the effect of fan speed on the power output of a wind turbine.

Using solar panels to generate electricity from the sun is becoming increasingly common. Solar panels can be used at many scales to generate power. A single, small panel can be used to charge electronic devices such as your cell phone. Large numbers of panels can function together to generate electricity for an entire neighborhood.

The amount of electricity that can be generated by a solar panel is affected by many variables. In this experiment, you will explore how the amount of current and voltage produced by a solar panel is affected by the distance to a lamp. You will then test your equipment in direct sunlight and calculate the efficiency of the photovoltaic cell when converting the energy from the sun into electrical energy.

Using the sun to heat water is not a new idea. Humans have been harnessing the thermal energy of the sun for centuries. Today, solar thermal systems are found on rooftops around the world, providing affordable, pollution-free hot water for millions of people.

In most US homes, water is heated using electricity, natural gas, or oil. Since most of our electricity is generated from fossil fuels, it is safe to say that most water in the United States is heated using energy from fossil fuels. The burning of fossil fuels releases pollution into the environment and is believed to contribute to global climate change.

Since it takes a large amount of energy to heat water, it can be a significant portion of our energy bills. Replacing a traditional water heater with a device that can heat water using energy from the sun is not only good for the environment, it can also be a great way to save money on your energy bill.

Solar collectors take advantage of the greenhouse effect in order to heat water. Have you ever noticed how surprisingly warm it is inside a car that has been parked in the sun? Sunlight easily passes through the glass windows and is converted into heat when it hits the interior of the car. Some of that heat passes back through the glass, but a lot of it gets trapped inside. In a solar collector, this trapped heat warms the water that is circulating through the system.