Thursday, January 13, 2011

Guest blog #11 - Dr. Jack Edelstein's thoughts on conservation and entropy

"What do we mean by the term ‘energy conservation’ or more generally ‘resource conservation?’  At first thought, the answer seems obvious:  conservation means using less stuff, thereby making a smaller environmental footprint than would have otherwise been made, and avoiding a certain disruption to the resource base (e.g. biodiversity) that would have otherwise occurred.  What, exactly, is it that needs to be conserved, and how does conservation actually work?

From a practical point of view, absolute conservation would completely preserve the current status of the earth’s biodiversity -- by neither depleting any natural resource (e.g. wildlife, trees, water), nor by depositing any man-made matter onto the environment (e.g. trash, smog, and carbon).

There are four ways that we can conserve energy, and any other [non-renewable] resource -- 1) consume less, 2) eliminate waste, 3) increase efficiency, 4) substitute renewable.  We will describe each of these four conservation methods through the simple example of a shower. 

The first way to conserve is to actually consume less water by reducing the shower time, and/or by reducing the flow of the showerhead.  Another way to consume less is to lower the water temperature, thereby reducing the amount of energy used (in heating the water).

The second way to conserve is to eliminate or reduce waste.  We distinguish waste from excess by defining the former as the act of consuming resources without deriving any value -- as in the case of a dripping showerhead. Excess is much more subjective than waste -- e.g. taking a very long shower is not wasteful in the strictest sense (since some marginal benefit or utility is being derived), but at some point it becomes excessive in that the derived benefit is miniscule.

The third way to conserve is to increase efficiency by utilizing less resources in the creation of a given unit of output.  In the case of a shower, improved efficiency can be a low-flow showerhead, or a more energy-efficient water heater.  However, efficiency by itself does not lead to conservation, due to the Jevon's paradox (as explained in an earlier post by Darshan).

The fourth way to conserve is to substitute renewable resources for non-renewable ones.  An example is utilizing solar collectors to heat the water (instead of fossil fuel), and harvesting rainwater instead of drawing water from an underground aquifer.

                    Reduce         Eliminate     Maximize      Substitute   
               consumption        waste         efficiency      renewables   
Cost               Zero             Low       High          ???    

The expenses associated with these four conservation strategies range from zero to high cost -- depending on the level of technology required. Reducing consumption costs nothing since it is entirely a behavioral strategy.  Similarly, eliminating waste generally entails a behavioral approach augmented by a low input of technology. The ‘efficiency’ approach is generally technology-intensive and therefore expensive, and often risky.  Finally, the cost of substituting renewable for non-renewables is quite variable.  It is generally high in that it usually involves an advanced technology component, but it can also be low, as in the case of rain-water collection discussed above. 

A review of the academic literature as well as the general media reveals a strong bias toward energy conservation strategies that are based on the efficiency and renewable options -- the two more expensive options.  In other words, the two conservation approaches that cost the least and could have the most immediate impact -- i.e. to use less and to eliminate waste -- are the ones that are least supported, and often outright ignored. (There are a number of reasons for this, which will be addressed in a future post)

The power of Darshan’s project is that it represents by far the most cost-effective approach to conservation --  simply using less (though it may not actually be that simple to do).  By using absolutely less matter, Darshan is impacting the entire production chain associated with the consumption of physical goods.

Perhaps that’s why the name of this project is “Entropy”. If I understand the 2nd law of thermodynamics, one of the ideas it posits is that the physical world is constantly seeking a state of equilibrium, through a process defined as entropy.  As an outcome of the forces of entropy, the planet attained a state of equilibrium many millions of years ago, and this equilibrium was maintained until homo sapiens started roaming the earth.  The activities of humanity are increasingly disturbing this equilibrium, and the newly resultant equilibrium may become (or already is) inhospitable to sustained life.

The essence of conservation, then, is to understand that the equilibrium into which humanity entered was ideally suited to the evolution of homo sapiens and all other life.  Conservation entails respecting that equilibrium, and reduces our interference with it. Using less is the most powerful way we as individuals can conserve the planet."

~Dr. Jack Edelstein.

I love his last paragraph.


  1. We manufacture HighSierra brand low flow showerheads, a process that uses energy and raw materials and creates waste. We want people to buy these low flow showerheads because they feel better than other low flow showerheads, will not clog, and don't suck bacteria into the spray or cool off the water, the way aerating showerheads do.

    We have been feeling proud of ourselves because showerhead technology has been largely unchanged for years (see,other than the aerator showerhead, which has its drawbacks. Jevon's Paradox is an interesting concept for us. When people buy our showerheads, they are going to throw away their old showerheads, creating waste (resource consumption). Does that waste negate some of the good stuff a low flow showerhead does for the environment? Will people simply take more showers because they are saving money and the spray is pleasing? Thoughts?

  2. Oh boy this is a very interesting dilemma. Here are several rambling thoughts, and hopefully they mean something. If not, please tell me! =)

    I am an advocate of applying a consistent philosophy to everything I do, especially when it comes to the environment. So, for me, tradeoffs are a difficult thing. Indeed, I would prefer to avoid the tradeoff and not do whatever it is that is putting me in the position to make a tradeoff. But I will talk about tradeoffs here.

    The amount of water used in showers, based off of what little I know, is very small compared to the amount of water used in the rest of our daily lives, especially for those people who eat meat. Meat production uses a lot of water, and some estimates say that a pound of beef requires approximately 2500 gallons of water, enough for an average daily shower for six months. At the same time, showering seems to be one activity many of us do quickly, almost out of necessity. My gut says that only a fraction of showers we take we take for leisure. We are either showering quickly in the morning so we are in time for work, or we might go a day or two without showering. Apparently, the average American showers approximately five times per week. Hmmm, I am not so sure people will shower much longer if they used low-flow showerheads. But at the same time, as you know, water is going to be THE key issue in the next twenty or thirty years, with most of the US and world to experience severe water shortages in that time frame. Maybe there might be some policy or change in water rates because of that, I am not sure.....

    Yes, I'm rambling, but that's just because I just don't know how to approach your question. I will talk to Jack Edelstein the next time I see him and post back here on his thoughts. Definitely check back on the 27th or 28th of January...

    Thank you so much for taking the time to comment!

  3. Message to the Nozzle Guy from Jack Edelstein:

    Your thoughtful post actually raises two separate issues.

    The first is a cost-benefit question. Is the "avoided" footprint of the water that is (presumably) saved by the new shower-head (during its entire life) of greater value than the actual ‘end-to-end’ footprint of the new shower-head -- i.e. the footprint that is created in producing the new showerhead, in disposing the old one, and finally in disposing of the low-flow showerhead at the end of its life cycle. As you can imagine, this cost benefit calculation is very difficult to analyze, given all the possible variables and possibilities.

    The second issue about whether the water saved by the low-flow showerhead may cause people to take longer showers (since the cost to them will be the same), thereby using the same amount (or more) of water as with the old showerhead. This is the Jevons paradox -- I actually prefer the term "rebound effect".
    The answer is that the new showerhead might in fact lead to reduced water usage in your house (micro-level) but it may increase usage at the macro level.

    I think that Jevons’ (1 September 1835 – 13 August 1882) original example is a good one to grasp his paradox. He observed that as the process of producing coal became more efficient, coal became more plentiful and hence cheaper. People had an incentive to use more instead of less -- because the lower cost per unit enabled them to use more coal on the same budget. People could afford to build larger furnaces to generate more heat at the same (or lower) cost. New uses for coal could be found (steamships, trains, factories, etc.)

    The rebound effect states that even if all the people in the world were to use low-flow showerheads, the total amount of water used would not decrease -- the ‘avoided’ water would just be used elsewhere (like for more private swimming pools). So the ultimate message of the rebound effect, to my understanding, is that efficiency by itself leads to more consumption rather than less, unless the supply of the material -- whether coal or water -- diminishes.

    How to diminish the supply is a whole other topic, that maybe I’ll address that in a future post.