Carbon and Buildings
Choose the right systems
       Air source heat pump
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Choose the Right Systems

Buildings which are in use currently make up 28% of our global carbon emissions.

These emissions come from the energy consumed to use, maintain and repair buildings and are collectively known as operational carbon emissions of the building sector. Choosing the right building systems can help us reduce this impact significantly.

Air source heat pump


What are building systems?

Building systems refer to all mechanical, electrical and plumbing components that work together to make a building function properly to people to use and occupy comfortably. 

  • Mechanical Systems include Heating, Cooling, Ventilation and Air Filtration systems also known as HVAC.

  • Electrical Systems act like the central nervous system of the building, taking power from the grid and supplying it to lights, appliances, and all components that are powered by electricity including security and fire safety systems.

  • Plumbing systems include domestic hot water tanks, water pipes, stormwater drainage and sewage systems.

All building systems are powered by energy. This energy comes from several sources that release varying degrees of greenhouse gases.

Currently building systems in Canada are mainly powered by:

  • Natural Gas which is a fossil fuel. The largest component of natural gas is methane, and it also contains carbon dioxide and other hydrocarbons. When natural gas is burnt - typically to heat homes - all these greenhouse gases are released into the atmosphere.

  • Electricity which is generated from various “clean” sources like hydro and nuclear that do not release greenhouse gases as well as “dirty” sources like coal, petroleum and natural gas that are fossil fuels. Whether you are on a clean or dirty “electricity grid” depends on which province you are in.

  • Wood or biomass contains carbon which is released as carbon dioxide when wood is burned to heat spaces or water in homes.

  • Heating Oil is also known as diesel or kerosene which is derived from petroleum, and therefore a fossil fuel. It has a very high carbon footprint.

Natural gas, most commonly used for space and water heating, is Toronto's largest source of building sector emissions, accounting for 54% of community-wide emissions.

In a province like Ontario, which runs on a clean energy grid (see map below) electrifying building systems is a major pathway to reducing operational carbon.

Map courtesy of Natural Resources Canada, 2017.

In Canada space heating makes up 62% of the total residential energy use.

       How can you reduce the carbon impact of space heating?
  • Upgrade from a gas furnace system to a heat pump system that is more energy efficient and will soon be cheaper to operate thanks to carbon pricing.

  • Properly insulate basements, walls, ceilings and attics

  • Improve air-tightness of your home by minimising pathways for air leakage through walls, windows and doors.

Water heating makes up 19% of the total residential energy use.

       How can you reduce the carbon impact of water heating?

  • Upgrade from a gas powered boiler system to a heat pump water heater system that is more energy

  • Install low-flow fixtures on showerheads and faucets

  • Use dishwashers and clothes washers in full loads

  • Use cold water when possible

Appliances, Lighting, and Space Cooling make up the remaining 19% of residential energy use. 

       These are already powered by electricity, but you can do              the following to reduce your consumption and save money          on your utility bills:

  • Use heat pumps for cooling in place of air conditioners

  • Use Energy Star certified appliances

  • Use LED light bulbs

  • Use outdoor lights with motion detectors

  • Use multiple switches and light dimmers

  • Turn off unnecessary lights