If it’s an exciting alternative fuel, if it’s novel or bizarre, it’s probably healthy for the planet, right? Most proponents of alternative transportation fuels will haughtily tout that anything not petroleum based is good for the environment and highly beneficial to our new sustainability economic regime. And that holds water in theory, but if it doesn’t hold carbon, it might not be completely true.
Not every alternative fuel stands up to practical application in the real world. Net carbon neutrality, though, is a prime criterion by which an alternative fuel can be gauged to be Earth friendly. I’ll use solar-powered and electric cars supplied with electricity from forest biomass as examples.
What comes out of the tailpipe? For most automotive consumers, end-of-the-pipe pollution is their bottom line and sometimes, sadly, where their curiosity about living green ends. On the plus side, electric and solar-powered vehicles discharge no carbon pollutants, and this makes them extremely popular options.
Is the source a carbon sink? Solar energy is not. In fact, the radiation from the sun heats up the world’s oceans, which then release carbon into the atmosphere. Forests themselves generally have a carbon-negative effect on the environment. As trees grow, they sequester carbon at very fast rates that decline proportionally to the age of the tree, but since most tree species have relatively long life spans, they can store carbon up to hundreds or thousands of years.
How is the energy harnessed? In the case of solar energy, the location of it is literally everywhere, and it requires no human or machine work to capture, so it is carbon neutral. Biomass is also an abundant natural resource, but it’s not evenly distributed throughout the planet where it’s needed most. Canada has massive tracts of forested land that could be converted to biomass fuel, but that would require a lot of transportation energy to harvest and transport to the nearest biomass-gasification plant, an intensive carbon-emitting process.
How is it refined? With solar energy, of course, there’s no need for this step. It comes in a completely usable form. Forest biomass must be chopped down and pulverized (which takes machine energy and emits carbon), and more carbon is expelled during combustion when it’s generated into electricity.
Technically, nothing is completely environmentally safe. Even if you biked to work, you’d still release small amounts of CO2 when exhaling! But knowing the benefits and drawbacks of each type of fuel is important for you as a consumer and a voter.