What is the meaning and importance of embodied energy as a measure of sustainability and why we need to develop widely accepted standards for embodied energy? This article explores this somewhat arcane concept that seeks to measure how much energy is “embodied” in a product or service; in other words how much energy is used throughout the entire life cycle of the thing being measured including the energy required by decommissioning, disassembly and deconstruction.
When people compare products (or services) typically they look at the feature set, reputation for quality and compare the price tag. Although this is certainly important, if one is concerned about sustainability, it is also important to look at the impact that the product or service has over its entire life cycle — i.e. from cradle to grave, from mine to manufacture to market and to end of service life. In other words to look at a given product or service and trace its impacts, the impact of mining or harvesting the materials used to make it, its packaging and transportation costs as well as the cost of operating it over its expected service life and the recoverability of the materials that go together to comprise it. This is the sustainability view of a product or service and I believe that this way of measuring cost is as important for us all as the dollar value that is assigned to it.
When I look around at things… at everything from a towering building to a can of humble beans in a supermarket aisle; from a shiny new automobile to a Smart Phone, or even at something like a service say a financial or information transaction I am lead to wonder about what the embodied energy is for that thing… and to measure and compare things using this metric. While the embodied energy is not the only sustainability metric – there are others such as the percentage of recycled content, or whether a product is made from materials that are grown in a sustainable manner for example; embodied energy is certainly an important aspect of any product or service from a sustainability perspective.
Embodied Energy Accounting is not an Exact Science
Coming up with the embodied energy for something or some service activity is not an exact science, but it is usually understood to include the energy used throughout the entire production value chain from resource acquisition to final packaging and distribution. Most often it also attempts to account for the cost of decommissioning or disposing of something as well so that the embodied energy in a computer for example would account for the energy cost in recycling and/or disposing of the computer. What goes into coming up with the embodied energy of something is thus somewhat arbitrary and in order to make a fair comparison with other similar products or services it is important to establish that in all cases similar factors were accounted for and included (or conversely excluded) from the calculations.
However notwithstanding the lack of clear and binding standards for energy accounting and the resulting need to carefully factor how the final published number was arrived at, energy accounting is still very valuable and comparing embodied energy content of two products, services or project proposals can help decision makers and consumers evaluate and compare products, services or proposals. This brings us to the need for standards.
Clear and Widely Recognized Standards of Measurement Are Needed
A fair number of Energy Star and other energy efficiency ratings have been created by the DOE and other standards bodies that attempt to measure and rate the relative energy consumption of products and provide a consumer friendly ranking system – i.e. the Energy Star – so energy efficient products can use it to promote their energy efficiency. This is important work and energy efficiency standards and prominent labeling has already resulted in significant energy savings and avoided carbon dioxide emissions. For example a report titled “Acting Globally: Potential Carbon Emissions Mitigation Impacts from an International Standards and Labeling Program” by Letschert, Virginie E. finds that around 850 million metric tons of CO2 emissions could be avoided in buildings in the industrialized and industrializing market zones covered by the study if energy efficiency standards and labeling were introduced and progressively improved on – over time — in the world’s most important economies.
Important as energy efficiency standards are they do not fully capture the broader concept of embodied energy, which also naturally depends on energy efficiency during use, but in addition attempts to capture the wider energy consumption history and future energy costs that will be incurred if the choice is made to go with one product or service over another.
And this is an important consideration that decision makers should be aware of and factoring into the decision process. Better and agreed upon standards would help make this an easier goal to accomplish and to present.
Like the related concept of Energy Returned on Energy Invested or ERoEI (sometimes seen as EREI) embodied energy needs to tackle the thorny issue of boundary considerations and any standards that evolve need to be able to clearly determine what goes in and conversely what stays out of the accounting process and how various factors must be quantified and weighted.
For those who want to read more in detail about ERoEI see our article: “Energy Returned on Energy Invested (ERoEI) And Why It Matters”, which goes into some depth on what ERoEI means and why it matters.
Awareness of Embodied Energy Remains Elusive, but is Needed Now More than Ever
Attempting to formulate embodied energy standards forces those who try to confront many devilish details and across multiple levels of analysis and this is why it is so hard to accomplish. For example, how does one compare energy of different types, such as coal, gas, hydro, wind etc.. If we reduce energy to its thermal potential measured say in BTUs or QUADS say then low value energy such as soft brown coal gets a higher weight proportionately than higher value energy sources such as jet fuel or electric power.
Clear embodied energy standards – specialized for clearly defined product and service categories – could potentially result in large overall realized energy savings and CO2 reductions as has been shown by the savings already realized by energy efficiency ratings such as Energy Star. As these standards evolved and finally stabilized and gained traction and wider adoption this would also help promote the consideration of embodied energy in the decision making process.
More in general, an increased awareness of the concept and outlook of embodied energy in what we use and in how we live our everyday lives, is needed more than ever. We need to begin looking at ourselves and at our actions and choices adding into the mix of factors that influence our choices the still poorly understood and not well known concept of embodied energy. It is perhaps the most significant and certainly is one of the most significant measures of the final end impact and costs of products and services. The evolution of standards and best practices in formulating embodied energy will help, but we must do more, in order to educate ourselves on this profoundly different way of viewing things and the world we live in.
In my opinion the time has arrived for humankind to add concepts such as embodied energy and ERoEI to the lexicon of ideas and meta tools we inhabit our heads with. It is a needed skill and viewpoint, but remains one that is largely lacking in our world that is even now rushing towards an approaching global fossil energy cliff.
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© 2010, Chris de Morsella. All rights reserved. Do not republish.