All transportation fuels have an environmental impact
This is the second in a series of posts addressing common myths about refining and transportation fuels. In this entry, let’s clear up a few misconceptions about the environmental performance of alternative fuels.
Myth: Alternative fuels are better for the environment than petroleum fuels.
Fact: There is no such thing as a “clean” fuel. All transportation fuels have an environmental impact.
Electricity, natural gas, biofuels, gasoline and diesel – each is an alternative fuel when it comes to today’s transportation. Each has its strengths and weaknesses, whether we’re talking about energy performance or environmental impact. This is why we have alternatives – so that we can choose the right fuel and transportation mode to meet specific transportation needs.
Let’s take a closer look at the true environmental impact of some of these fuels.
Electric vehicles (EVs) often get high marks for their environmental performance. In some cases they are referred to as zero-emission vehicles (ZEVs). But how accurate is this claim? In environmental terms, how “clean” is an electric vehicle?
It is true that EVs produce no greenhouse-gas (GHG) emissions from their motors. Yet engine output is not the only measure of a vehicle’s emissions. In fact, they are measured in much broader and more detailed terms through what are called lifecycle analyses (LCAs). These rigorous scientific studies assess all emissions related to a vehicle. That means taking into account the full lifespan of the vehicle and its components, from production to eventual disposal and recycling. The manufacturing of all vehicles produces a carbon footprint. Some EV manufacturing is burdened with further environmental impact due to the mining of rare earth minerals in the production of current battery technologies. As much as 70% of the world’s cobalt – one of the most expensive elements in battery production – comes from the Democratic Republic of the Congo, a country that has been widely criticized for its labour practices.
Although EVs may not emit GHGs on the road, the electricity they rely on to charge batteries is often the source of GHG emissions. In many jurisdictions around the world, including Asia, Europe and the U.S., burning coal is one of the leading ways to generate electricity. An EV offers few environmental benefits in that scenario. The good news for Canada is that about 80% of our electricity is already renewable and emissions-free.
Fuel-cell electric vehicles (FCEVs) are being promoted as a cleaner EV alternative. FCEVs generate power using hydrogen stored in a pressurised tank and a fuel cell. This technology does promise high GHG emissions-reduction potential in the long term, depending on the carbon intensity of its production. For example, methane reforming is one approach currently used to produce hydrogen, but this is an emitting process that offsets some of the technology’s environmental gains.
Natural gas and propane (methane)
Natural gas and propane already power various commercial and municipal fleet vehicles, including taxis, transit and school buses, refuse trucks, local delivery and heavy freight trucks. Natural-gas vehicles (NGVs) produce up to 25% less GHG emissions compared to gasoline or diesel equivalents. But their numbers are very small. Fewer than 13,000 NGVs are currently in service in Canada – only a few hundred more than in 2010. There are more propane vehicles on the road in Canada – about 100,000 mostly light-duty vehicles.
More widespread adoption of gaseous fuels has to date been hindered by high upfront vehicle costs, the absence of a comprehensive refueling infrastructure, and ongoing technology, performance and business viability risks and uncertainties.
As these impediments fall away, the transformation opportunities for gaseous fuels are primarily in commercial and government fleets. Propane is a lower emissions solution more suited to light and medium duty vehicles; natural gas is more suited to medium and heavy-duty vehicles.
Other technologies are not standing still
While some transportation-fuel alternatives strive for commercial viability, petroleum products and the vehicles they power are continually improving their environmental performance. We’ll look at this in more detail in our next Mythbuster post.