The Difference Between Efficiency and Using Less

In its basic definition, efficiency relates to a given amount of energy or effort it takes to accomplish a certain task relative to the least possible amount. It is true that a more efficient system/solution/product will use less energy than a less efficient counterpart, but in order to gauge its place within the topic of sustainability we have to ground the term and its use in realistic conditions. What we end up with is that “efficiency” is a much more incomplete thought that most people treat it. As an idea, it is a component of a direction more than a solution.

A Call for Saving Energy

There are many environmental voices that champion opportunities for our culture to use increased efficiency as a way to reduce the amount of energy and resources that we sacrifice. Amory Lovins famously claimed that Americans have the opportunity to cut their energy use by 30% merely through efficiency measures alone. In 2009, the McKinsey & Company issued a report claiming that not only that “the US economy has the potential to reduce annual non-transportation energy consumption by roughly 23 percent by 2020,” but that it was financially in our best interest to do so by “eliminating more than $1.2 trillion in waste—well beyond the $520 billion upfront investment (not including program costs) that would be required.”

This is why the idea of efficiency is so attractive. It is presented as a solution that is not only currently good for the environment, but also is cash flow positive for us in the long run. Even better yet, if efficiency can be baked into things like products, infrastructure or the built environment then perhaps we don’t really have to change much at all. What’s not to like? Onward with efficiency!

But there’s a danger to these kinds of mindsets and the misconceptions that they promote for sustainability. As I have lectured about in the past, the most important aspect of sustainability that I try to impart on others is that sustainability is not a technological fix to supplement a wasteful lifestyle. This is incredibly important. This doesn’t mean that using compact fluorescents, plug-in hybrids, rechargeable battees or EnergyStar appliances is unsustainable, but it means that these things do not embody sustainability. Sustainability is the lifestyle. It is the mindset of using what we need–which for most of us is less than what we use now–in order to help maintain a level of resource balance.

This reality ends up presenting itself in how our culture has responded to cases of increased efficiency in the past. Take some of the large energy-consuming items in the American home for example. The Department of Energy has regulated the efficiency requirements for certain household items since oil embargo in 1973 (perhaps one of the first times that American energy use was called into question on the national level). Since then, things like furnaces, hot water heaters, air conditioning units and heat pumps need to achieve certain levels of energy efficiency in order to be code compliant. The thought would be that it would help make homes more efficient over time, helping us to use less energy as a country… but such is not the case. Despite these efficiency increases, the energy consumption of Americans has remained flat ever since.

Courtesy of Terrapin Bright Green

Butter’s in the Fridge

Another great example is a look at refrigerators in America. If we start with a fridge from 1947, the data suggests that the size of refrigerators has increased over 250% over half a century. However, after peaking around 1974, the energy used by the appliance has decreased to the point of nearly reaching parity with its ancestry of the late 40’s. Despite an increase in size, the energy load of our fridges can be nearly the same 50 years later due to an 25-fold increase in efficiency. Good stuff, no? Proponents like Lovins would call this a win-win, saying we can use efficiency to lower our energy footprint even as we increase capacity.

But according to New Yorker writer David Owens, not so fast. In his book, The Conundrum (I highly recommend it), Owens outlines some of the indirect repercussions of increased efficiency in refrigeration. I’ve taken some of his assertions into an Intercon diagram below.

The first caveat to this efficiency story is it’s important to remember that while fridges have gotten more efficient it is not uncommon for houses to have increased their cooling load beyond a single fridge. A separate chest freezer, back-up fridge or even wine coolers are all increasingly normal. Also, just because a household replaces their kitchen fridge with a newer model doesn’t mean the old fridge is retired. These older counterparts often find homes as back-up cold storage in basements or garages to keep spare beverages ready for things like football games or beer pong. While perhaps a net increase in enjoyment, it also constitutes a net increase in energy.

As refrigeration has gotten cheaper and easier, it has spread across our commercial landscape as well. Owens asserts that gas stations of today have the same amount of cold storage that grocery stores had in the 50’s and 60’s.

Let’s not forget the contents of these evolving appliances as well. The potential kicker in this equation is that as food capacity and reliability has grown, so has our assumption that food will last longer inside the fridge. As a result, our culture ends up throwing away more food that ultimately goes bad despite staying cold. Since 1975 our food waste has increased by 50% to the point that we now throw away 40-50% of the food that we grow. How does that factor into energy? Our food is incredibly energy intensive. Wasted food represents resources required for fertilizer and pesticides (both petroleum based), harvesting, packaging, transportation and the cooling in both the stores and in our homes. Not to mention that rotting food is the primary source of methane in landfills, a potent greenhouse gas. So in the end, has our increased efficiency actually saved us energy in the long run? It’s certainly debatable.

Just Using Less

The simple change to the equation that makes it much more environmentally viable is pairing efficiency with a sustainable use of resources of materials–or rather a lack of use. If we each had only one efficient fridge that only stored food that we were actually going to eat then the gains would be more measurable. Efficiency only gives us the gains we choose to preserve and build from, but it also gives us an opportunity to consume more. The same can be said for most of our “green” options today (low-flow fixtures, CFLs, geothermal heating and cooling, hybrid cars). Replacing a product with one that uses half as much energy, but is used three times as much is a step back, not a step forward.

As disappointing as it may be, the solution to our environmental problems will most likely not be a technological fix. It will not be a product that makes it cheaper to consume. The prospect of efficiency should be taken as a supplement, a beginning to a more sustainable lifestyle, not a replacement for sustainability. At this stage in our cultural and technological evolution, lifestyle changes will gain us far more ground than trading one consumption path for another.