 Solar Energy is renewable energy that is powered by the sun.  Solar energy can be converted into other forms, such as heat and electricity.

 On a clear day, the sun gives off around 1,000 watts of energy per square meter of the planet’s surface. This is enough energy to power all of the homes in the world.

PROSCONS Solar panels give off no pollutionSome pollution occurs in manufacturing the panels. Quiet energyInitial cost is high but little or no cost thereafter. ($1000 or higher per home. ) Can be used in most areas of the Earth and even on overcast days. Generates electricity only during daylight hours. Can be used in remote areas. Do not need to connect to power grid. Weather can affect the efficiency of solar cells Can be installed directly on buildings.

 Wind energy is renewable energy that is powered by the wind. Wind may be used to create electrical power.

 A wind turbine changes wind energy into electricity. The wind turns the giant blades of the turbine. This creates a current through an electrical generator.

 Pennsylvania is the leader on the east coast of the United States in wind energy production.

 Current Wind Speed in the United States Current Wind Speed in the United States  Need 5 to 10 mph wind speed to work.

PROSCONS Wind turbines take up less space than the average power station and ground around them may be used for other purposes. Wind can be unreliable. Wind is free and easy to get to.Wind turbine construction can be very expensive. Can be used in remote locations and can be built in different sizes. Can create noise pollution. Quiet turbines are being developed. Non-polluting other than in manufacturing of wind turbine. Unsure of environmental impact on wildlife such as birds and bats.

 Hydropower energy is renewable energy that is powered by moving or falling water. Hydropower can be used to create electricity. It is called hydroelectricity.

 The flowing water that often comes from large rivers and dams turns the blades in a water wheel. The water wheel is called a hydraulic turbine. The rotation of the blades creates a current through the electrical generator.

 Hydropower is one of the oldest sources of energy. People used hydropower thousands of years ago to turn wheels that ground up grain.

PROSCONS Can store water and control flooding. Requires flooding large areas. Provides recreational activities and/or a supply of drinking water. Disrupts natural river flow. Produces clean power.Ends flooding that cleans silt from rivers. Simple design makes for inexpensive repairs and low maintenance costs. Expensive to build Dams can break in flood situations.

 Geothermal energy is renewable energy that is powered by heat from the earth. This energy can be used to create electricity.

 By drilling into the earth’s crust, people can access trapped steam and hot water. The heat, in the form of steam, turns the giant blade of a water wheel called a turbine. This creates a current through an electrical generator.

PROSCONS Geothermal energy is clean.Geothermal power plants work best in areas like California, Hawaii and Iceland. Hot water from the ground is reused in a closed system. Some minerals are removed from the water used in the system. (sulfur) One a plant is built, the production of energy is practically free. May cause small tremors or earthquakes if area is unstable. Geothermal power plants have a high capacity factor, they run continuously day and night with an uptime typically exceeding 95%

 Biomass energy is renewable energy that is powered by organic material from plants and animals. Biomass energy can be used as fuel.

 People use many different kinds of plants to create biomass energy. Some of these plants include switchgrass, corn and sugarcane.

 The old way of converting biomass to energy is simply to burn it to produce heat. This is still how most biomass is put to use. The heat can be used directly, for heating, cooking, and industrial processes, or indirectly, to produce electricity. The problems with burning biomass are that much of the energy is wasted and that it can cause some pollution if it is not carefully controlled.  A number of noncombustion methods are available for converting biomass to energy. These processes convert raw biomass into a variety of gaseous, liquid, or solid fuels that can then be used directly in a power plant for energy generation.

 Vegetable oil is generated from sunlight and CO 2 by plants. It is safer to use and store than gasoline or diesel as it has a higher flash point. Straight vegetable oill works in diesel engines if it is heated first. Vegetable oil can also be transesterified to make biodiesel, which burns like normal diesel.l

PROSCONS Biomass can use waste from agriculture to create energy. Needs large areas for growth of biomass crops. Biomass is abundant on earth and found all over the planet. Competes with food production. When methods of biomass production other than direct combustion of plant mass are used, such as fermentation and pyrolysis, there is little effect on the environment. Direct combustion of any carbon- based fuel leads to air pollution similar to that from fossil fuels. Since CO 2 is first taken out of the atmosphere to make the vegetable oil and then put back after it is burned in the engine, there is no net increase in CO ₂. Pollution may occur in farming process.

 Ocean energy is renewable energy that is powered by ocean tides and waves. This energy can be used to create electricity.

 People harness energy from ocean tides and waves through turbines. The rotation of the blades creates a current through electrical generators.

PROSCONS Non-polluting except in the manufacturing of units. May hinder ship traffic or cause damage to marine systems. Cheaper than producing fossil fuel power. (About 1/5 th the cost) Tides cycle every 12.5 hours. Useful in coastal areas.Tides vary seasonally and monthly.