Decarbonizing Space Heating in Canada
March 1, 2023
Fossil fuels heat most Canadian homes and buildings and transitioning to renewable energy sources for space heating won’t be easy.
Electrification of space heating is often positioned as our only pathway for decarbonization but that is not true.
Around the world, district heating systems are connecting millions of consumers to a growing portfolio of renewable energy sources including geothermal, solar thermal, renewable electricity, biofuel, and waste heat recovery.
Canadian cities need robust heat strategies to ensure the complete range of renewable energy source and technologies are being considered to meet their heating needs.
Broadening our view of renewable energy
Asked to think about renewable energy, our minds quickly jump to images of solar panels and wind turbines. So, perhaps it is not surprising we turn so quickly to electrification as the only solution.
Yet, solar panels and wind turbines are only two renewable energy technologies developed to master renewable primary energy sources.
Primary energy sources are harvested directly from a natural resource and fall into two categories – primary energy flows and primary energy fuels.
Primary energy flows are considered renewable because they are naturally replenished. They include the sun’s radiant energy and the heat released from the Earth’s core as well as the kinetic energy of moving water and air.
Primary energy fuels, on the other hand, include fossil and nuclear fuels. They are considered fuels because energy is stored within them. When this energy is used, it is gone. So, they are non-renewable. Primary energy fuels include coal, natural gas, crude oil, and uranium and they create waste: carbon and nuclear waste, respectively.
While plant biomass is also a primary energy fuel, it is considered renewable as it can be replenished if managed in a sustainable manner. Plants produce biomass from solar energy through photosynthesis. The combustion of biomass releases stored chemical energy as heat. Biomass can also be converted to renewable liquid or gaseous fuels.
We would be wise to explore how we can master as many renewable primary energy sources as possible to build the most reliable, affordable, and climate-friendly energy system.
Primary energy sources are often converted into a more transportable form of energy.
Secondary energy sources – or energy carriers – include electricity, gasoline and diesel, and heat. Gasoline and diesel are being replaced with electricity in the transportation sector. Hydrogen is an emerging energy carrier being considered for the energy transition.
Like electricity, heat and hydrogen can be produced using renewable and non-renewable energy source.
However, unlike hydrogen and heat, Canada has a well-established distribution network to deliver electricity to consumers.
Jurisdictions with well developed distribution networks for heat have an additional tool in their energy transition toolbox which Canadian cities do not have – district heating. Globally, district heating systems are connecting consumers to a wider range of affordable and reliable renewable energy sources including geothermal, solar thermal, renewable electricity, biofuel, and waste heat recovery.
This puts Canadian cities and consumers at a disadvantage in the transition to a low carbon economy.
District heating systems allow for economies of scale since the generation of heat in a few centers is more efficient than having thousands of boilers each heating individual buildings. It also cheaply captures and delivers valuable energy otherwise wasted in electricity generation, industrial and other processes and redistributes that energy to other consumers.
Many community energy plans identify district heating as an important part of an integrated approach to reduce energy consumption, emissions, and costs.
National and provincial policy makers need to turn some of their attention towards the use of heat as an energy carrier and begin investing in district heating infrastructure.