21 September 2010

Seeing the Light

At the Albuquerque Journal, John Fleck has an excellent piece on technological advances in lighting technology and Jevons Paradox.  Here is an excerpt:
Jeff Tsao's 1999 white paper on the case for next-generation, super-efficient light bulbs makes a point so obvious that it seems to require no explanation.

A solid-state light bulb that uses half the electricity of conventional bulbs would cut lighting-related energy consumption in half, right?

"The worldwide amount of electricity consumed by lighting would decrease by more than 50 percent," the Sandia Labs researcher and his colleagues wrote, "and total worldwide consumption of electricity would decrease by more than 10 percent."

A decade later, Tsao's thinking has evolved.

In a new paper, a team led by Tsao has drawn international attention by arguing that, instead of leading to reduced energy consumption, super-efficient bulbs may instead lead to people simply using more light.
What is this?  Advances in efficiency might presage greater energy consumption?!

That is right.  Fleck explains:
To understand why, take a trip to the villages in rural Costa Rica where Michael Fark has been working.

Fark heads a Canadian nonprofit called Lighting Up The World, which has been trying to get the super-efficient light bulbs developed by people like Tsao into the hands of the people who need them most.
There, one- or two-room clay brick houses are usually lit by candles or kerosene lamps.
It is lousy light by our standards, barely enough for the young Costa Ricans to do evening schoolwork after a day of helping in the fields. But that light, dim as it may be, is so precious that families spend up to 30 percent of their cash flow on candles or kerosene for a few hours of light per day, according to Fark.
Give the Costa Rican farm families a more efficient way to light their homes, as Fark's organization is doing, and they will choose to consume more light, not less energy.
Multiply their predicament by some 2 billion people in poverty around the world, and you enter the counterintuitive world of "the Jevons paradox."
Here is how I described Jevons Paradox one year ago:
The paradox was described in 1865 by William Stanley Jevons as follows:
It is wholly a confusion of ideas to suppose that the economical use of fuel is equivalent to a diminished consumption. The very contrary is the truth.
As a rule, new modes of economy will lead to an increase of consumption according to a principle recognised in many parallel instances. . .

Now the same principles apply, with even greater force and distinctness, to the use of such a general agent as coal. It is the very economy of its use which leads to its extensive consumption. It has been so in the past, and it will be so in the future. Nor is it difficult to see how this paradox arises. . .

And if economy in the past has been the main source of our progress and growing consumption of coal, the same effect will follow from the same cause in the future. Economy multiplies the value and efficiency of our chief material; it indefinitely increases our wealth and means of subsistence, and leads to an extension of our population, works, and commerce, which is gratifying in the present, but must lead to an earlier end. Economical inventions are what I should look forward to as likely to continue our rate of increasing consumption.
Some people have suggested that Jevons Paradox means that efforts to become more efficient are misguided. Others, seeing such arguments being made have tried to claim that Jevons Paradox actually does not exist. Both lines of argument are badly misguided.

Jevons Paradox is very real. It tells us that increasing efficiency is necessary if we are to met energy needs, because those energy needs will continue to grow even in the face of rapid growth in efficiency. Thus, the practical consequences of the paradox are that we need to become more efficient and we need more energy, all at once. How efficient we can become will of course influence the amount of energy that we need, so improving efficiency is a worthy goal. But no one should imagine that efficiency gains alone can eliminate the need for more energy -- they can't and they won't. Policy needs to be able to focus on advancing efficiencies and creating ever greater sources of energy.


  1. I believe that this was covered in Peter Huber's 2005 book "A Bottomless Well" wherein he argued persuasively that CAFE standards increased fuel consumption across the economy.

    David Charlton

  2. There is also another problem...

    The farther north you live the more time and energy you spend heating your buildings.

    The waste heat from lighting fixtures heats the building. In fact, all of the energy that doesn't go out the window in the form of light will eventually heat the building.

    If the light bulbs are more efficient then they will heat the building less. You will then have to increase the amount of energy you use to heat the building. This will further offset the savings of the energy efficient light bulbs.


  3. While people are unlikely to increase their usage of lighting all that much (I'm not going to add extra lamps when the number I have is perfectly sufficient for my needs just because lighting is cheaper), they'll probably shift the energy gained into other uses. This results in a richer population and, to me, is a very good thing.

    Hugh - Conversely, air conditioning will be used less in the summer.

  4. Christoper said "Conversely, air conditioning will be used less in the summer."

    True, but in countries like Canada, where I live and where the government has outlawed incandescent bulbs starting in 2012, we use way more energy for heating than air conditioning. (Note the "further north" part of my original comment.)

    Southern countries may get more benefit but it is an empirical question as to how much benefit there is overall.

    Hugh Whalen

  5. Personally, I doubt incandescent lights provide all that much benefit for heating. Yes they put out close to 60 watts in heat, but that 60 watts is not distributed with heating a room in mind. Much of it goes into another material (like the ceiling) and the air that gets heated does not get circulated. Nor can it regulate when it's on or off base on room temperature.

    You're probably better off just going with a dedicated heater.

  6. #5 Christopher,

    Obviously you have never encountered Radiant Electric Ceiling Heat.