Renewable Energy Sources Renewable Sources Renewable Energy Source: An energy source that can be replaced in a relatively short period of time. Examples: hydro-electric, wind, solar, biomass and geothermal Hydroelectric Generation: the energy of falling water is used to move the large blades of turbines connected to generators. Many use the water stored behind a dam to generate electricity. The dam controls to flow of water. There are 180 hydro-electric generating stations in Ontario. AdvantagesDisadvantages Does not release pollution into the air or water Disrupts natural flow pattern Restrict fish movement Habitat loss Expensive to build. Difficult to find a good location Niagara Falls Power Photovoltaic Generation: Changes light energy from the Sun directly into electrical energy. Uses photovoltaic cell to convert the energy Advantages/Disadvantages of Photovoltaic Generation: AdvantagesDisadvantages Free and readily available Can be installed anywhere Does not create pollution Expensive and inefficient Can only work during the day. Wind Generation: A modern wind turbine is made up of large blades mounted on a tall tower. As the wind blows, the blades of a turbine turn. The turbine is connected to a generator. Advantages/Disadvantages of wind AdvantagesDisadvantages Wind is free Building and maintaining wind farms is less expensive then fossil fuels or uranium Disrupts scenic views Need large areas Noise pollution Disrupts migrating birds. Thermal Generation Using Biomass: Biomass, or biofuel, is any form of bacterial, plant, or animal matter. Biomass is burned to produce thermal energy. This heats water into steam that can turn a turbine connected to a generator to produce electricity. Advantages/Disadvantages of Using Biomass: AdvantagesDisadvantages renewable Produces greenhouse gases Using crops as fuels results in lower food production. Geothermal Generation: Geothermal generation uses wells drilled deep underground to access thermal energy. Hot geothermal gases are then piped to a generating station, where the thermal energy turns water into steam. Advantages/Disadvantages of Geothermal: AdvantagesDisadvantages Energy always present deep in earths crust. Can be reheated and reused. No greenhouse gases Suitable areas are rare. Generating stations are difficult and expensive to build. What Does the Future Hold? In Ontario, about 26% of all electrical energy comes from burning coal and natural gas, 52% from nuclear sources. This means that 78% of Ontarios electrical energy is produced using non-renewable energy sources. Therefore, we need to develop ways to use less electrical energy!!! Jack Layton's house