The keystone of the green economy is a drastic increase in energy and other resource efficiency as well as in learning how to make do with a lower consumption of increasingly scarce physical resources. Increasing our societies energy efficiency is the single most vital and important thing we need to do in order to have a green economy or in fact any kind of economy at all. It is also vitally important to throttle back the amounts of fossil fuel we burn in order to mitigate and diminish the rapid and potentially catastrophic climate change that is being driven by our fossil fuel habit.
Without much more energy efficient buildings, transportation systems as well as industrial and agricultural systems nothing we can do will be able to prevent an economic collapse brought about by the inevitable and rapidly approaching decline in the recoverable supplies of all forms of fossil energy and other resources. We simply cannot build out wind, geothermal, biofuel, or solar energy fast enough to sustain our civilization in the face of rapidly shrinking recoverable fossil energy reserves, unless we embark on an urgent and sustained drive to use energy (and other resources) with much higher efficiency. The world’s energy realities dictate that we need to both reduce waste and to learn to live with less.
We need to conserve and become more efficient with the resources we do use. This is especially the case with energy because at the center of everything sits energy; energy is needed for all activities and to extract and distribute all other resources. This makes energy efficiency, conservation and learning how to get by with less energy the keystone of building the green economy. It is this unique position that energy occupies that makes it the most critical problem we need to address and is why the title of this article is “Its Energy Efficiency Stupid”. This is not to say that other resource efficiencies are not critical because they are; for example fresh water scarcity is a huge and growing domestic and international problem. However unless we can become much more energy efficient we will never even begin to be able to address these other resource scarcity issues.
Exajoules and Quads, How Energy Use is Measured
There are two prevailing units being used to measure large scale generic energy use. Most of the world uses the exajoule as the standard unit of energy measurement. One exajoule equals 10 to the 18 (10E18) joules. This is a huge number of joules; it is one billion billion joules.
A joule is the work done when the point of application of a force of 1 newton is displaced through a distance of 1 metre in the direction of the force. One joule is equivalent to 1 watt-second, 107 ergs, 0.2390 calories, or 0.738 foot-pounds or to put this in everyday terms a joule is around the amount of energy it takes to lift a small apple a distance of one meter or conversely the energy released when dropping a small apple one meter.
The other unit of energy being used is the quad, which stands for quadrillion BTU. One quad is about 1.055 exajoules. This is the unit of energy measurement used by the US Department of Energy. To appreciate just how much energy this is it helps to see it in term of some energy equivalents. For example one quad contains around the same amount of energy as do 36 million tons of coal, 293 billion kilowatt-hours, or a little more than 8 billion gallons of gas.
Expressing energy in terms of exajoules or quads is useful as a general measurement of energy use and as a rough yardstick by which to compare energy sources. One can think of it as a lowest common denominator for energy, reducing all energy to the same base unit for the purpose of comparison. However it is important to understand that in the real world energy is not so interchangeable. Each energy system needs to be understood in its own terms. Thus for example electric energy is unique and has its own set of unique issues and unique uses, which other containers of energy (coal for example) cannot be substituted for without first converting the chemical energy in the coal in this case into electricity.
How Much Energy Are We Talking About and Where Are We Burning It
In 2005, total worldwide energy consumption was 500 exajoules (or around 474 quads) with 80-90% derived from the combustion of fossil fuels. The US itself currently uses more than 100 quads of energy per year. According to the Annual Energy Review of 2007, residential buildings accounted for 21% of the total US energy consumption in 2007, while commercial buildings accounted for 18%, transportation for 29% and industry used 32% respectively. The breakdown of US energy consumption by sector for 2005 is as follows: residential buildings 21.7 quads, commercial buildings 17.9 quads, industrial 32.5, transportation 28.1 quads.
What immediately jumps out from this breakdown of energy use is just how large of a percentage of our total energy consumption is comprised by our residential and commercial buildings. Taken together they amount to 39% of all the energy our nation uses.
First Harvest the Low Hanging Fruit
There is a lot that can be done almost immediately in each of these sectors and especially in the commercial and residential buildings and in the transportation sectors. The industrial sector has implemented a lot of the easy steps already as high energy costs have impacted the bottom line and driven these large energy consumers to seek out ways to improve their processes and save.
We should zero in on this low hanging fruit that can significantly reduce our energy consumption through improvements in the efficiency with which we use energy and cutting the waste of energy. It may not be the most glamorous stuff, but it is doable now and will have a lasting impact that will keep providing dividends into the future. This is especially true in the residential and commercial building sectors. Many of the easy improvements in energy efficiency and cutting down on waste are as simple as adding insulation, sealing leaky windows, replacing incandescent lighting with energy efficient lighting and so forth.
We Can Do Lighting Heating and Cooling Much More Efficiently than We Are Doing
Around 20% of the electricity we consume is consumed to light our homes and buildings. Current compact fluorescent lighting uses only 25% the energy as incandescent bulbs do and LED lights, which are rapidly becoming more affordable, use even less energy.
To read more about energy efficient lighting see our post: LEDs, Lighting the Way to Energy Efficiency
Heating and cooling account for about 56% of the energy use in a typical U.S. home, making it the largest energy expense for most homes. For commercial buildings figures vary depending on the type of building and business activity that the structure supports. For example hot water heating can account for a very large percentage of the energy use (as high as 40%) in restaurants and in lodging, but will account for a much smaller percentage of total energy use in office buildings for example. In any case it is clear that heating and cooling is a large factor of commercial buildings total energy use.
Improving weatherization of the nation’s homes and commercial buildings could save significant amounts of energy and is something that can be done immediately and that does not require new technologies or infrastructures. Many buildings can save up to a third of the energy they currently consume by sealing leaky cracks, installing energy efficient windows and adding insulation. For example a DOE program to help weatherize low income housing saw an average of 32% energy savings for homes in the program.
In addition to weatherization and using energy efficient lighting a vast amount of energy could be saved by widely adopting the technology of geothermal heat pumps (GHPs), which are also known as ground-source heat pumps. Current GHPs use between 30% to 40% less energy than air sourced heat pumps do and can be improved and made even more efficient. They are applicable anywhere and are very reliable and long lasting systems.
To read more about geothermal heat pumps see our article: Geothermal Heat Pumps: Good for the Bottom Line, Good for the Nation and Good for the Earth
Green roofs are another avenue that is available to make our buildings more energy efficient by absorbing the heat energy from the sun before it is absorbed into the building. In cold climates, the superior insulating qualities of green roofs help reduce heat loss. Studies have found that green roofs reduce solar heat gain by as much as 95% and reduce cooling needs from 25 – 50%. They also offer other important benefits such as water filtration and retention and reducing storm surge runoff as well as aesthetic improvements of the urban space.
What About the Car Culture?
Transportation is a much thornier issue than energy saving in buildings, which is pretty easy to get people to agree on. Americans have long had a love affair with the car and our society in many ways can be said to be a car culture with most everything we do being built around the automobile. It is very hard to get Americans to even think about abandoning the car or even curtailing their use of automobiles. Even trying to improve the mileage of the nation’s automotive fleet has been very difficult and as a result our country has one of the world’s most energy inefficient transportation systems. Our public passenger rail network is second rate compared to the extensive and modern systems in Europe and Japan and many American cities are cursed with severely underfunded rudimentary mass transit systems that poorly serve their citizens.
To be without a car in our country is in many ways to be a second class citizen. In many places life is almost impossible without a car.
We need to do more to improve mileage efficiency of cars (and trucks), to find ways to use them less (such as promoting car pooling) and we need to make a serious commitment to laying down a mass transit systems in our towns and cities. Mass transit is not cheap; it represents a major capital expenditure, but it is something that we need to be doing. The same is true for improving our inter-city passenger rail network.
Conclusion
Some day in the not too distant future we will either thank ourselves for having had the foresight to make these vital investments in making our society much more energy efficient or else curse ourselves for having failed to prepare ourselves for a future that in retrospect will become painfully obvious to even the most obstinate deniers. In the long run we cannot wish our energy problems away – even though that is what many Americans seem to be doing today. If we do not become proactive begin to adopt a long haul investment in energy efficiency now we will be facing catastrophic collapse in the coming decades as our society rolls over the fossil energy cliff woefully unprepared for the realities of energy scarcity that are bearing down on us whether we know they are or arduously pretend that they are not.
In conclusion one really can turn the famous and oft repeated phrase and say: it is energy efficiency stupid.
