Rethinking Sustainability Myths

by ‐ Tags: alternative energy, green living

There are innumerable blogs out there that post articles claiming to debunk common misconceptions about sustainability (we should know, you’re reading one right now!).  A blog post is a great way to introduce a topic and get some discussion going, but is almost never going to serve as a definitive answer to a complex question. 

As consumers, voters, and engaged human beings, we need to be wary of anybody claiming to know what is best: best for the planet, best for our health, best for our wallets.  An overly simple answer to a complicated question should tip you off that everything might not be as it seems.

The terms “green” and “sustainability” get tossed around quite a bit these days, which has led to a proliferation of “definitive” solutions to our problems.  A healthy skepticism toward extravagant or surprising claims helps level heads prevail when discussing complex problems.  Here are a two examples of familiar sustainability topics that are more complex than you might have thought.

 

Public Transportation is More (or Less) Efficient than Driving

 

A Familiar Story:

Public transportation is more energy efficient than driving, because if trains and busses can carry more passengers, the gallons per passenger-mile are lower. The same principle explains why carpooling is more efficient than driving 4 cars. 

A New Twist:

Recently, some transportation experts have noted that public transit is not always more efficient than if the equivalent passenger load had been transported via passenger car.  While a full bus does carry more passengers on less fuel, an empty bus, or a bus with only a few passengers, uses significantly more fuel than if those people had driven their cars.  What’s worse, a whole transit system running at all hours of the day with sub-optimal passenger loads can (sometimes) be less fuel efficient than if the whole system were scrapped and everybody drove!

A Complicated Issue:

In the case of mass transit, understanding that low occupancy is not energy efficient does not equate to public transportation being bad for the environment.  What is does mean, is that transportation experts have a challenging job to balance rider demand with frequency of bus/subway traffic.  

The solution is not to trash our public transit, nor is it to build costly and expansive transit systems everywhere we like.  Instead, planners and policy makers must be judicious when evaluating mass transit as an investment, and think through the complicated planning needed to effectively and efficiently balance different modes of transportation.

Local Food is Better for the Environment than Nationally-Distributed Food

 

A Familiar Story:

Foods that are grown and eaten locally have less carbon emissions associated with them since they are not transported thousands of miles by gas-guzzling trucks, planes, and ships.  Smaller farms practice more holistic farming techniques, reducing the use of synthetic fertilizer and pesticide. 

A New Twist:

In terms of energy use, foods that are grown in warmer, sunnier regions can offset the “food mile” effect by being easier to grow.  Trying to grow fruit and tomatoes commercially in the northeast will be much more energy intensive than growing the equivalent amounts of food in sunny Florida or California, where plants grow easily in fertile soil. Furthermore, large farms can take advantage of economies of scale in order to produce food more efficiently.

A Complicated Issue:  

While it may be the case that it is cheaper and easier to grow most food in some locations and ship it to far-off end markets, there are other important factors to consider beside energy use.

For example, when people talk about locally grown food they often mean food grown on small, independently owned farms, possibly organically.  This stands in contrast to the large “factory farms” that are the source of most food in supermarkets.  Local farms can offer benefits beyond efficiency, such as bolstering to local economies, or restoring unused or depleted land.

These are just two examples of the kinds of complicated debates that arise when talking about sustainability, though similar issues abound in all controversial issues. When it comes to the issues that we broadly label as “sustainability” or “green” the best answers are difficult to succinctly define, and are unique to the particular situations of each individual, business, or community.