How does Energy Work?In physics, energy is defined as the capacity to do work. Essentially it is the ‘currency’ for doing things. Work is calculated by multiplying the power required to complete a task by the amount of time the task takes. For example, if it takes 1000 joules (one of several units used to measure energy) of energy to push a table for five seconds, then pushing that table used an average of 200 Watts (another unit) of power over the course of those five seconds.
Energy takes many different forms, like light, heat, and sound, and is measured using several different units, like joules, calories, and British Thermal Units (BTUs). When discussing energy as it pertains to sustainability, we typically talk about both heat and electrical energy, and we use either kilowatt hours (kWh), or BTUs as our units. Think about a lamp in your living room: if the lamp has a 100 watt lightbulb, and is left on for ten hours, then the work done by that lamp (providing light for ten hours) used one kWh of electrical energy (100W x 10h = 1000Wh = 1kWh).
What Makes Energy Unsustainable?The problem with our current energy practices and systems is that we already use an inordinate amount of it, and as global societies develop and populations expand, the amount that we use will only increase. Using energy in and of itself is not a bad thing; unfortunately, in most places it is generated unsustainably using fossil fuels. Fossil fuels are unsustainable for a variety of reasons:
- They are a non-renewable resource – the use of fossil fuels is a very linear process. We extract the fuel, combust (use) it, and then it is gone. Fossil fuels take thousands of years to form naturally, and so our energy systems are currently dependent on a resource that will run out in the near future.
- The extraction process is environmentally damaging – the harvesting of fossil fuels, usually by drilling or fracking, comes at a tremendous financial and environmental cost. It destroys wildlife habitat, pollutes waterways, and contaminates the land to the point where it is unusable by people or animals.
- Their combustion creates air pollution – particularly with dirty fuels like coal, combustion of fossil fuels releases harmful pollutants like particulate matter and nitrous oxides, which poison the air and harm human health.
- They emit greenhouse gases – likely the most common concern regarding the combustion of fossil fuels for energy production. Fossil fuels, also known as carbon fuels, emit greenhouse gases into the atmosphere when they are burned. Greenhouse gases emitted from fossil fuel combustion are one of the main causes of anthropogenic climate change. Climate change is an incredibly important sustainability challenge that will completely change human and natural systems around the world.
BC's Energy MixUnbeknownst to many people, British Columbia is already ahead of many regions with respect to sustainable energy generation. As their name suggests, BC Hydro, the province’s major electric utility, is largely powered by hydro-electric dams. If fact, over 90% of the electricity supplied by BC Hydro is generated using hydro power and an additional 5% is generated using other renewable sources. This means that turning on the lights in your home in BC comes at a much smaller financial and environmental cost compared to a home in Germany or Australia. These countries burn large amounts of coal to produce electricity, which releases huge amounts of greenhouse gas and other pollutants in order to meet the electricity demand.
This is not to say that energy generation in British Columbia is perfect. Space heating and cooling of commercial and residential buildings is the largest use of energy in the province, and it is largely supplied by natural gas. Though it is often considered to be cleaner than other fossil fuels, natural gas remains a carbon fuel that harms the environment through extraction and GHG emissions. This is the reason why buildings emit more greenhouse gases than any other sector.
Transportation is the second highest emitting sector, as most people still use gasoline-powered passenger vehicles (cars) to move from point A to point B. These two sectors combine for almost 70% of BC’s greenhouse gas emissions because the energy used to supply them is carbon based. Given that electricity generation in the province is largely clean and emits few greenhouse gases, converting our building and transportation energy systems to electric power would go a long way towards reducing emissions for the province; and ensuring sustainable energy for future generations.