Embodied energy
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Embodied energy is the sum of all the
Embodied energy is an accounting method which aims to find the sum total of the energy necessary for an entire
History
The history of constructing a system of accounts which records the energy flows through an environment can be traced back to the origins of
The main methods of embodied energy accounting as they are used today grew out of
Methodologies
Embodied energy analysis is interested in what energy goes to supporting a
Standards
The SBTool, UK Code for Sustainable Homes was, and USA LEED still is, a method in which the embodied energy of a product or material is rated, along with other factors, to assess a building's environmental impact. Embodied energy is a concept for which scientists have not yet agreed absolute universal values because there are many variables to take into account, but most agree that products can be compared to each other to see which has more and which has less embodied energy. Comparative lists (for an example, see the University of Bath Embodied Energy & Carbon Material Inventory[8]) contain average absolute values, and explain the factors which have been taken into account when compiling the lists.
Typical embodied energy units used are MJ/kg (mega
Related methodologies
In the 2000s drought conditions in
Data
A range of databases exist for quantifying the embodied energy of goods and services, including materials and products. These are based on a range of different data sources, with variations in geographic and temporal relevance and system boundary completeness. One such database is the Environmental Performance in Construction (EPiC) Database developed at The University of Melbourne, which includes embodied energy data for over 250 mainly construction materials. This database also includes values for embodied water and greenhouse gas emissions.[11] The main reason for differences in embodied energy data between databases is due to the source of data and methodology used in their compilation. Bottom-up 'process' data is typically sourced from product manufacturers and suppliers. While this data is generally more reliable and specific to particular products, the methodology used to collect process data typically results in much of the embodied energy of a product being excluded, mainly due to the time, costs and complexity of data collection. Top-down environmentally-extended input-output (EEIO) data, based on national statistics can be used to fill these data gaps. While EEIO analysis of products can be useful on its own for initial scoping of embodied energy, it is generally much less reliable than process data and rarely relevant for a specific product or material. Hence, hybrid methods for quantifying embodied energy have been developed,[12] using available process data and filling any data gaps with EEIO data. Databases that rely on this hybrid approach, such as The University of Melbourne's EPiC Database,[11] provide a more comprehensive assessment of the embodied energy of products and materials.
In common materials
Selected data from the Inventory of Carbon and Energy ('ICE') prepared by the University of Bath (UK) [8]
Material | Energy MJ/kg | Carbon kg CO2/kg | Material density kg/m3 |
---|---|---|---|
Aggregate | 0.083 | 0.0048 | 2240 |
Concrete (1:1.5:3) | 1.11 | 0.159 | 2400 |
Bricks (common) | 3 | 0.24 | 1700 |
Concrete block (Medium density) | 0.67 | 0.073 | 1450 |
Aerated block | 3.5 | 0.3 | 750 |
Limestone block | 0.85 | 2180 | |
Marble | 2 | 0.116 | 2500 |
Cement mortar (1:3) | 1.33 | 0.208 | |
Steel (general, av. recycled content) | 20.1 | 1.37 | 7800 |
Stainless steel | 56.7 | 6.15 | 7850 |
Timber (general, excludes sequestration) |
8.5 | 0.46 | 480–720 |
Glue laminated timber | 12 | 0.87 | |
Cellulose insulation (loose fill) | 0.94–3.3 | 43 | |
Cork insulation | 26 | 160 | |
Glass fibre insulation (glass wool) | 28 | 1.35 | 12 |
Flax insulation | 39.5 | 1.7 | 30 |
Rockwool (slab) | 16.8 | 1.05 | 24 |
Expanded Polystyrene insulation | 88.6 | 2.55 | 15–30 |
Polyurethane insulation (rigid foam) | 101.5 | 3.48 | 30 |
Wool (recycled) insulation | 20.9 | 25 | |
Straw bale | 0.91 | 100–110 | |
Mineral fibre roofing tile | 37 | 2.7 | 1850 |
Slate | 0.1–1.0 | 0.006–0.058 | 1600 |
Clay tile | 6.5 | 0.45 | 1900 |
Aluminium (general & incl 33% recycled) | 155 | 8.24 | 2700 |
Bitumen (general) | 51 | 0.38–0.43 | |
Medium-density fibreboard | 11 | 0.72 | 680–760 |
Plywood | 15 | 1.07 | 540–700 |
Plasterboard | 6.75 | 0.38 | 800 |
Gypsum plaster | 1.8 | 0.12 | 1120 |
Glass | 15 | 0.85 | 2500 |
PVC (general) | 77.2 | 2.41 | 1380 |
Vinyl flooring | 65.64 | 2.92 | 1200 |
Terrazzo tiles | 1.4 | 0.12 | 1750 |
Ceramic tiles | 12 | 0.74 | 2000 |
Wool carpet | 106 | 5.53 | |
Wallpaper | 36.4 | 1.93 | |
Vitrified clay pipe (DN 500) | 7.9 | 0.52 | |
Iron (general) | 25 | 1.91 | 7870 |
Copper (average incl. 37% recycled) | 42 | 2.6 | 8600 |
Lead (incl 61% recycled) | 25.21 | 1.57 | 11340 |
Ceramic sanitary ware | 29 | 1.51 | |
Paint - Water-borne | 59 | 2.12 | |
Paint - Solvent-borne | 97 | 3.13 |
Photovoltaic (PV) Cells Type | Energy MJ per m2 | Energy kWh per m2 | Carbon kg CO2 per m2 |
---|---|---|---|
Monocrystalline (average) | 4750 | 1319.5 | 242 |
Polycrystalline (average) | 4070 | 1130.5 | 208 |
Thin film (average) | 1305 | 362.5 | 67 |
In transportation
Theoretically, embodied energy stands for the energy used to extract materials from mines, manufacture vehicles, assemble, transport, maintain, and transform them to transport energy, and ultimately recycle these vehicles. Besides, the energy needed to build and maintain transport networks, whether road or rail, should be taken into account as well. The process to be implemented is so complex that no one dares to put forward a figure.
According to the Institut du développement durable et des relations internationales, in the field of transportation, "it is striking to note that we consume more embodied energy in our transportation expenditures than direct energy", and "we consume less energy to move around in our personal vehicles than we consume the energy we need to produce, sell and transport the cars, trains or buses we use".[13]
Jean-Marc Jancovici advocates a carbon footprint analysis of any transportation infrastructure project, prior to its construction.[14]
In automobiles
Manufacturing
According to
An electric car has a higher embodied energy than a combustion engine one, owing to the battery and electronics. According to Science & Vie, the embodied energy of batteries is so high that rechargeable hybrid cars constitute the most appropriate solution,[17] with their batteries smaller than those of an all-electric car.
Fuel
As regards energy itself, the factor
According to some authors, to produce 6 liters of petrol requires 42 kWh of embodied energy (which corresponds to approximately 4.2 liters of diesel in terms of energy content).[18]
Road construction
We have to work here with figures, which prove still more difficult to obtain. In the case of road construction, the embodied energy would amount to 1/18 of the fuel consumption (i.e. 6%).[19]
Other figures available
Treloar, et al. have estimated the embodied energy in an average automobile in Australia as 0.27 terajoules (i.e. 75 000 kWh) as one component in an overall analysis of the energy involved in road transportation.[20]
In buildings
Although most of the focus for improving energy efficiency in buildings has been on their operational emissions, it is estimated that about 30% of all energy consumed throughout the lifetime of a building can be in its embodied energy (this percentage varies based on factors such as age of building, climate, and materials). In the past, this percentage was much lower, but as much focus has been placed on reducing operational emissions (such as efficiency improvements in heating and cooling systems), the embodied energy contribution has come much more into play. Examples of embodied energy include: the energy used to extract raw resources, process materials, assemble product components, transport between each step, construction, maintenance and repair, deconstruction and disposal. As such, it is important to employ a whole-life carbon accounting framework in analyzing the carbon emissions in buildings.[22] Studies have also shown the need to go beyond the building scale and to take into account the energy associated with mobility of occupants and the embodied energy of infrastructure requirements, in order to avoid shifting energy needs across scales of the built environment.[23][24][25][26]
In the energy field
EROEI
Final energy has to be multiplied by in order to get the embodied energy.
Given an EROEI amounting to eight e.g., a seventh of the final energy corresponds to the embodied energy.
Not only that, for really obtaining overall embodied energy, embodied energy due to the construction and maintenance of power plants should be taken into account, too. Here, figures are badly needed.
Electricity
In the
In France, by convention, the ratio between primary energy and final energy in electricity amounts to 2.58,[27] corresponding to an efficiency of 38.8%.
In Germany, on the contrary, because of the swift development of the renewable energies, the ratio between primary energy and final energy in electricity amounts to only 1.8,[28] corresponding to an efficiency of 55.5%.
According to EcoPassenger,[29] overall electricity efficiency would amount to 34% in the UK, 36% in Germany and 29% in France.[30]
Data processing
According to association négaWatt, embodied energy related to digital services amounted to 3.5 TWh/a for networks and 10.0 TWh/a for data centres (half for the servers per se, i. e. 5 TWh/a, and the other half for the buildings in which they are housed, i. e. 5 TWh/a), figures valid in France, in 2015. The organization is optimistic about the evolution of the energy consumption in the digital field, underlining the technical progress being made.[31] The Shift Project, chaired by Jean-Marc Jancovici, contradicts the optimistic vision of the association négaWatt, and notes that the digital energy footprint is growing at 9% per year.[32]
See also
- Biophysical economics
- Crystalized labor
- Ecological economics
- Embodied emissions
- Energy accounting
- Energy cannibalism
- Energy economics
- Environmental accounting
- Life cycle assessment
- Systems ecology
References
- ISBN 978-0-521-42689-3.
- ISBN 978-0631171461.
- ISBN 978-0-8229-7215-0.
- ^ Leontief, W. (1966). Input-Output Economics. Oxford University Press. p. 134.
- OCLC 20211746. Docket CFW-88-08. Archived from the original(PDF) on 30 September 2007.
- PMID 4758118.
- ^ Lenzen 2001
- ^ a b G.P.Hammond and C.I.Jones (2006) Embodied energy and carbon footprint database, Department of Mechanical Engineering, University of Bath, United Kingdom
- ^ CSIRO on embodied energy: Australia's foremost scientific institution Archived 2006-02-25 at the Wayback Machine
- S2CID 109032580.
- ^ OCLC 1132202846.
- S2CID 116770528.
- ^ Chancel, Lucas; Pourouchottamin, Prabodh (March 2013). "L'énergie grise : la face cachée de nos consommations d'énergie". Propositions (in French). IDDRI.
- ^ Jancovici, Jean-Marc (30 December 2017). "Pour un bilan carbone des projets d'infrastructures de transport" (in French).
- ^ a b (de) Volkswagen environmental report 2001/2002 Archived 2016-03-03 at the Wayback Machine see page 27
- ^ (fr) Life cycle assessment Archived 26 July 2015 at the Wayback Machine website www.ademe.fr see page 9
- ^ (fr) Science & Vie # 1213 October 2018. see pages 48 till 51.
- ^ (de) Final energy analysis: gasoline vs. electromobility website springerprofessional.de
- ^ energy-and-road-construction website www.pavementinteractive.org
- .
- ^ "Understanding the lifespan of a Japanese home or apartment". JAPAN PROPERTY CENTRAL. 7 February 2014. Archived from the original on 4 July 2019.
- .
- ISSN 0378-7788.
- .
- ISSN 1088-1980.
- ISSN 0961-3218.
- ^ (fr) "Decree of 15th September 2006 on the energy performance diagnosis of existing buildings for sale in mainland France", website legifrance.gouv.fr
- ^ (de) laws in Internet Archived 31 July 2020 at the Wayback Machine site web gesetze-im-internet.de see section 2.1.1
- ^ EcoPassenger website ecopassenger.org, run by International Union of Railways.
- ^ EcoPassenger Environmental Methodology and DataUpdate 2016 website ecopassenger.hafas.de; see page 15, table 2-3.
- ^ (fr) Will digital revolution increase our energy consumption? website decrypterlenergie.org, website of association négaWatt.
- ^ (fr) Lean ITC website theshiftproject.org; see page 4.
Bibliography
- Clark, D.H.; Treloar, G.J.; Blair, R. (2003). "Estimating the increasing cost of commercial buildings in Australia due to greenhouse emissions trading". In Yang, J.; Brandon, P.S.; Sidwell, A.C. (eds.). Proceedings of the CIB 2003 International Conference on Smart and Sustainable Built Environment, Brisbane, Australia. OCLC 224896901.
- Costanza, R. (1979). Embodied Energy Basis for Economic-Ecologic Systems (Ph.D.). University of Florida. OCLC 05720193. UF00089540:00001.
- Crawford, R.H. (2005). "Validation of the Use of Input-Output Data for Embodied Energy Analysis of the Australian Construction Industry". Journal of Construction Research. 6 (1): 71–90. .
- Crawford, R.H.; Stephan, A.; Prideaux, F. (2019). Environmental Performance in Construction (EPiC) Database. Melbourne, Victoria, Australia: The University of Melbourne. .
- Lenzen, M. (2001). "Errors in conventional and input-output-based life-cycle inventories". Journal of Industrial Ecology. 4 (4): 127–148. S2CID 154022052.
- Lenzen, M.; Treloar, G.J. (February 2002). "Embodied energy in buildings: wood versus concrete-reply to Börjesson and Gustavsson". Energy Policy. 30 (3): 249–255. .
- Treloar, G.J. (1997). "Extracting Embodied Energy Paths from Input-Output Tables: Towards an Input-Output-based Hybrid Energy Analysis Method". Economic Systems Research. 9 (4): 375–391. .
- Treloar, Graham J. (1998). A comprehensive embodied energy analysis framework (Ph.D.). Deakin University. .
- Treloar, G.J.; Owen, C.; Fay, R. (2001). "Environmental assessment of rammed earth construction systems" (PDF). Structural Survey. 19 (2): 99–105. .
- Treloar, G.J.; Love, P.E.D.; Holt, G.D. (2001). "Using national input-output data for embodied energy analysis of individual residential buildings". Construction Management and Economics. 19 (1): 49–61. S2CID 110124981.