Energy is first and foremost a demand issue- how much do we need and for what ?- and yet the majority of public debate on the issue is to do with finding new sources of supply so as to allow industrial growth to continue.

Community Powerdown is concerned with redesigning our living arrangements as far as possible so as to reduce demand. We need to reduce drastically both per capita energy consumption as well as total world energy use.

This is an essential point to understand because simply making energy use more efficient, or even reducing per capita consumption, will not be sufficient if total demand is still increasing- for example, driven by rising population.

This means that we will sometimes have to make hard decisions about what we use energy for.

Energy is fundamental but one of the challenges of understanding energy in today’s’ world is that we are so unaware of how much we use or what the impacts of its use are. Taking more responsibility for how we use energy is the starting point.

In order to understand better our use of energy it is useful to consider the laws of thermodynamics, and how they impose absolute limits on energy consumption in society. By understanding this we will be able to make better choices about the use of energy in society.

Howard Odum {Odum, H., Odum, E. Energy Basis for Man and Nature 1976} has done much to show how energy is fundamental to not just the physical world, but also the social and even the psychological world:

“Citizens who think of energy as simply one commodity, separate from matter, information, art, and human spirit, must learn that everything has an energy component. The more intangible and valuable something is the more it costs in energy. And the more intangible a value is the more energy value is lost when it deteriorates or is lost”.

Thus, energy is not just for physicists: everyone in all sectors of society should become energy literate.

Odum explains the Laws of Thermodynamics in the following way:

  1. Energy cannot be created or destroyed. This is known as the Law of Conservation of Energy. We cannot “create” new sources of energy: either we use non-renewable sources which are essentially extracted from holes in the ground- including oil, gas and uranium- or we are confined to the availability of ambient solar energy that arrives on the planet each day. Thus, burning wood is renewable because trees can re-grow, but if we use the resource faster than the replenishment rate, it is no longer sustainable.
  2. The Law of Degradation of Energy. Without compensating changes elsewhere, heat can flow only from a hotter to a colder body. This is the law of entropy- the tendency for heat energy to become progressively more diffuse over time.
  3. Systems which use energy best survive. The maximum power principle explains that systems which use energy the most effectively are more likely to survive longer.

These energy laws together can be summed up by the concept of limits: there are absolute physical and natural limits to human activity on the planet, and we need to bring a deep understanding of this into every area of society.

One of the reasons it is so hard to accept the reality of these energy laws is that cheap oil has effectively been a source of “free” energy, allowing humans for one or two generations to escape the natural laws that hold all other life forms in check. With the rapid rise in technology, particularly computer processing power and communications technology, we have created a compelling illusion that we can delay pay-back time indefinitely.

Another reason is to do with the second law, the entropy law: ancient fossil energy stored deep in the ground represent potential energy; once they have been burned, that energy is dispersed throughout the environment, and some of its effect will turn up later as climate change, habitat destruction or pollution- often far removed from where it was consumed. So the consumer may be far removed from the results of that consumption.

Metaphorically, we might also perceive the effects of entropy in some of the common ills of modern society: traffic jams, road rage, road kill are all side-effects of a society using too much energy too fast. It has been estimated for example that the energy content of 40litres of oil would be roughly equivalent to three years of human physical labour- imagine pushing your car around over the same distance! And yet, in the past, and still over much of the planet, most work was done by human or animal labour. We need to prepare for a world where this will once again be the case.

Here are 6 points that should always be born in mind when discussing energy:

Firstly, the entropy law tells us that there will be consequences for the consummate use of energy that we have not yet paid for: the use of energy has a cost, in pollution, environmental destruction, and climate change.

Secondly, we take energy for granted: at the flick of a switch we can turn on powerful engines that can do the work of many people. The use of energy has allowed us evolve a new type of human- what William Catton calls “Homo Colossus”- a monstrous being with enormous energy at its disposal- and enormous capacity for destruction.{Catton, W., Overshoot 1982)

Thirdly, the use of energy has had an enormous effect on social relationships. The introduction of machinery has turned us from a mainly agrarian culture to an urban one in which much of the work is done by machines. We have lost many traditional skills that we may have to re-learn.

In addition, we have become extremely mobile and this has lead to families and communities being flung to the four corners of the earth. Commitment and retaining connection to the land is very hard when there are so many exotic opportunities for travel and adventure.

Fourthly, the rebound effect means that in a society dedicated to growth, improvements in efficiency without equal attention to reduction in overall demand may actually lead to an increase of energy, as that energy can now do more work and is therefore more valuable.

Fifthly, the energy return on energy invested is reducing. We have picked the low-hanging fruit and remaining energy supplies will be very costly to extract. This is known as “Energy Return on Energy Invested” or EROEI. Often, when a new oil discovery is reported for example, the energy cost required to extract the resource is not counted. In reality, much of the oil and gas in the ground will never be recovered because the energy to do so will exceed the energy it would provide.

Finally, energy is a social justice issue because worldwide, energy consumption is hugely inequitable. For example, Ireland’s per capita consumption of energy is only half that of the average American, but 4 times that of the average Cuban and nearly 8 times that of the average Indian. {World resource Institute 2007} While much of the developed world is still in denial about the reduced availability of energy in the future, most of the world will never experience the benefits of cheap fossil fuels that the West has had.

David Fleming calls the following issues the “Lean Energy Sequence”.

  1. Energy conservation: Develop all the ways you can think of to use energy more efficiently. Most energy in the United Kingdom and Ireland is used for heating, lighting, and the other energy-based services of buildings, so some simple changes such as turning the heating down can make significant savings. Aim to get the energy services you use now for less than half the energy you use now.
  2. Structural change: By changing structural aspects of your life- for example, by taking a job you can cycle to, or working part time so you can spend more time growing your own food- it may be possible to aim for ultimately an 80 percent reduction in total energy consumption. In this era of cheap energy, transport is the rule; doing things locally is the exception. When the energy famine comes, it will be the other way round. Better conservation can help to open the way to structural change; structural change can open the way to better conservation.
  3. Renewables. Living off the grid with domestic wind or solar systems will only be for the very few, partly because of cost and partly because few sites are suitable. Passive solar water and space heating will however be applicable to some extent in most places; but renewable energy production for the most part needs to be on a community or municipal scale, and its source will depend on the area.
  4. Institutional framework. If we are going to reduce and redesign our energy needs, and achieve the massive changes needed by the proximity principle, we will need a system in which we can all work to a common purpose. This will eventually mean some system of rationing- one such proposal is David Fleming’s Tradable Energy Quotas (

Re-thinking energy means exploring all of these issues together so that declining supplies of fossil energy are replaced, not with new sources of energy but with systems that promote community resilience.

This is the introduction to week four of the Powerdown Toolkit 10-week community learning course created by the Cultivate Centre in Dublin. It has an accompanying TV show with a 30-minute episode accompanying each week of the course, soon to be aired on Dublin Community TV.