The fine line between sustainable and green

By: Lex Coors

When I hear someone say “green energy,” my brain processes that phrase as “energy produced from renewable sources non-harmful to the environment.” Similarly, the phrase “sustainable energy sources” might bring to mind similar thoughts of environmental friendliness, but is that really what “sustainable” means?

Are these terms defined anywhere that we can all refer back to?

The result of this ambiguity is that you see a lot of companies claiming a % sustainable energy figure. While a lot of these companies use good, truly green sources of energy, there is a handful that skate by with the term “sustainable”.

Take nuclear power for example.

This may be up for debate, but, in my opinion, according to the definition of sustainable, “able to be maintained at a certain rate or level,” nuclear power fits the bill. This does not, however, mean that I believe nuclear power is green or environmentally friendly. Waste and byproducts should be part of the equation as well. And that’s just the beginning. There are many more sources of supposedly sustainable power that are deceptively harmful to the environment.

Let’s examine geothermal energy.  This involves drilling deep into the earth’s crust, where temperatures are very high, and adding water to the hot earth - using the steam created as a power source to drive steam turbines. Is it a sustainable form of energy production? You bet. What you don’t hear about in the press is the view that drilling that far down and disrupting the normal conditions of the earth can also create earthquakes and some of the alleged negative byproducts being arsenic, hydrogen sulfide (H2S) and carbon dioxide (CO2). Maybe it’s just me, but I’m not so quick to throw that into the non-harmful, Green category.

Another example would be energy produced from biofuels. Yes, biofuels are a cleaner option than fossil based fuels, but, then again, you’d be hard pressed to find something worse for the environment than an oil refinery – but I digress. Technically speaking, a biofuel is a fuel that contains energy from a geologically recent carbon fixation and is produced in a living organism. In layman’s terms, biofuels come from plants.  Trees are a renewable resource. Chop one down, plant another no problem. However the process used to cultivate the trees and power the plant has led some to believe the negative impact outweighs the positive (especially the way the leftovers from the process are burned; creating large smoke stacks).

In an effort to not sound like a pessimist, there are also highly underutilised forms of green energy that are also worthy of debate. Thorium-based nuclear power, for instance. (Ignore my earlier nuclear tirade. That was about uranium-based nuclear power.) Thorium could present several advantages over uranium, chief of which would be its short half-life meaning no long term storage will be necessary to house waste.  Also with Thorium, there is no plutonium, which means no potential to make nuclear weapons and no meltdown risk from reactors, as Thorium core power density is very low.

Sustainable power and green power are sometimes relative terms, and if truly green energy is important to your company you may want to dig a little deeper to find out exactly what supplier or energy type is used. We have to make a choice to clearly define these terms and categorise the different sources of energy, taking into account the end to end process and byproducts.

I believe that eventually we will be able to use sustainable energy sources in a true sustainable way, but until then let us mitigate the damage to nature as much as we can by educating and informing the mass consumers of energy.