Renewable energy is energy derived from the sources which are inexhaustible, or naturally replenished. As opposed to fossil fuels – which are currently used to power airplanes, many cars, heat buildings, and manufacture goods – renewable energy sources replenish themselves. Renewable energy sources include the sun, hydro (caused by flowing water, including rivers and oceans), wind, geothermal (heat from within the Earth), and biomass (burning vegetation and eating).
How it works
In most cases, people harness mechanical energy from a renewable source and transfer this energy to make electricity. There are six primary sources of renewable energy:
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| The Sun | Solar panels capture light from the Sun, and an attached converter and a transformer convert its energy into electrical energy. |
| Hydro | Hydraulic energy is created by the movement of water. Usually, dams are used to store hydro energy and release the right amount of water to water turbines. |
| Wind | Wind energy is obtained from moving air. The wind spins a turbine, which sends the mechanical energy through a shaft to a generator. |
| Ocean (tides and ocean currents) | Tidal energy generates power using reversible turbines in areas with high tide fluctuations. Ocean currents are used to spin turbines, which may either be fully submerged or placed on the ocean surface. |
| Geothermal | Geothermal energy comes from the heat within the Earth’s core. It is used to produce heat, which spins a turbine to generate electricity, and for residential and commercial heating in certain locations. |
| Biomass | Biomass energy is solar energy that has been captured by vegetation and stored in a form of matter that can be used as fuel which is combusted to generate electricity. |
Why it matters
Renewable energies allow us to generate electricity in a way that has a reduced impact on our environment, as they do not burn fossil fuels. However, it’s important to be aware that each of these sources face limitations; some are location specific, less efficient, or have an added environmental impact.
Efforts to develop clean, efficient, reliable, and cost-effective alternatives to fossil fuels are more important now than ever before. There is a major side effect of burning fossil fuels that is having a great impact on the planet: climate change. In the process of burning fossil fuels, carbon dioxide and other greenhouse gases are added to the atmosphere. These trap in radiation from the sun, and cause the planet to warm, and the climate to change over time. Outcomes of climate change include damage to ecosystems and extreme weather events that can lead to flooding, causing danger to coastal regions.
A Canadian connection
One young Canadian who has been using solar power to change the developing world forever is Calgary-born Eden Full Goh. As a high school student, she became concerned with the fact that so many people around the world go without electricity. To tackle the problem, she created a device called the SunSaluter, which is a solar rotator that uses a very simple drip mechanism to allow a solar panel to track the sun in the sky, generating up to 30% more electricity. As a bonus, it creates 4 litres of clean water in a day! It is so low-cost and efficient that it is now being distributed throughout areas without central power, and it is transforming lives.
Want to know more?
Learn about the physics of energy here.
Explore Canada’s environmental research and policy at Environment and Climate Change Canada.
Learn about Canada’s energy use and production on the Natural Resources Canada website.
Head over to Let’s Talk Energy to learn more about energy!
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