Sustainability 101: Renewable Energy

Written by: Kelsey Saunders

Welcome to the Sustainability 101 educational blog series! Our blog today will look at renewable energy.

Renewable energy refers to energy that is collected from a source that will not deplete with use overtime and of which can be replenished. Examples of renewable energy include wind energy, solar energy, and geothermal energy. Renewable energy can generally be divided into two types – thermal and electric. Additionally, these systems can be grid-connected or off-grid.

Thermal Energy

Thermal energy collection technologies capture renewable heat energy and uses it in the building for purposes such as space heating or for domestic hot water.

A geothermal energy system for heating, ventilation, and air conditioning brings a building in harmony with the earth beneath it, taking advantage of underground temperatures to provide heating in the winter and cooling in the summer.

Outdoor temperatures fluctuate with the changing seasons but underground temperatures don’t change as dramatically, all thanks to the insulating properties of the earth. Once you reach a certain depth, somewhere below 4 feet, the temperature of the earth is relatively consistent year-round. A geothermal system capitalizes on these constant temperatures to provide “free” energy. The result is a constant, comfortable temperature indoors, with an HVAC system that is out of sight, relatively maintenance free, and provides a healthy indoor environment for those occupying it.

Solar Thermal Energy is heat energy generated by a roof-mounted solar collection device that absorbs heat from the sun. Flat-plate collectors are the most common type, where fluid is circulated through tubing to transfer heat from the collection surface to an insulated water tank. This strategy can be used to pre-heat water from the municipal main, or well, to decrease the amount of energy needed by an on-demand water heater.

Electric Energy

Electric energy collection technologies capture the energy from a renewable source and converts it into electrical energy. Examples of this are wind power and solar electric power.

Wind Power

Wind Power is generated using turbines or windmills to harvest wind energy and then to convert it into electrical energy.

Solar Electrical Power is generated by photovoltaic (PV) modules that harvest energy from the sun and converts it into electrical energy. For use in buildings, solar modules can be integrated into the design as cladding components or as sun-shades which are mounted on the roof of the building or on land adjacent to it. Tracking devices working in tandem with the system can follow the path of the sun to ensure optimal exposure.

Another great technology to integrate into an electric renewable energy system is electro-mobility. This system refers to the use of electrically-charged vehicles as the major method of transportation. Electrically charged vehicles are shifting vehicle design away from the use of fossil fuels and carbon gas emissions to a more environmentally-friendly way of life. Running errands and going about your day just got a whole lot more sustainable!

Grid-Connected

Grid-connected systems are wired directly into the electric utility grid. Energy generated is sent back to the grid for storage and any energy the building uses draws directly from the existing grid.

Off-Grid

Off-grid systems are not connected to the existent utility grid. They use batteries to store the energy that is generated and use the energy directly in the building. Off-grid systems create opportunities for energy in areas that are not supplied by a utility grid. These systems can be small enough to power a home, or large enough to supply entire communities. Another advantage of off-grid living is that users are not susceptible to power outages!

Day in and day out we consume energy. Whether at work or school, our lives are dependent on the availability and accessibility of energy sources, however, we can all make conscious decisions to move towards sustainable and renewable energy and that goes from daily living right down to building construction.

Stay tuned for our next blog in the Sustainability 101 series!

*The Sustainability 101 lecture series is made as a supplemental learning initiative for high school students across Ontario