Sustainability 2011 , 3 , 1908-1943; doi:10.3390/su3101908sustainability
ISSN 2071- 1050
http://www.mdpi.com/journal/sustainabilityArticleSystem Energy Assessment (SEA), Defining a Standard
Measure of EROI for Energy Businesses as Whole Systems
Philip F. Henshaw 1,*, Carey King 2 and Jay Zarnikau 3(^1) HDS Systems Design Science, Synapse9.com, New York, NY 10040, USA
(^2) Center for International Energy and Environmental Policy, University of Texas, Austin, TX 78713 ,
USA; E -Mail: [email protected]
(^3) LBJ School of Public Affairs & College of Natural Sciences, University of Texas, Austin,
TX 78713, USA; E -Mail: [email protected]
- Author to whom correspondence should be addressed; E -Mail: [email protected];
Tel.: +1- 212.795- 4844
Received: 10 January 2010; in revised form: 12 October 2010 / Accepted: 12 November 2010 /
Published: 17 October 2011
Abstract: A more objective method for measuring the energy needs of businesses, System
Energy Assessment (SEA), measures the combined impacts of material supply chains and
service supply chains, to assess businesses as whole self-managing net-energy systems.
The method is demonstrated using a model Wind Farm, and defines a physical measure of
their energy productivity for society (EROI-S), a ratio of total energy delivered to total
energy expended. Energy use records for technology and proxy measures for clearly
understood but not individually recorded energy uses for services are combined for a whole
system estimate of consumption required for production. Current methods count only
energy needs for technology. Business services outsource their own energy needs to
operate, leaving no traceable record. That uncounted business energy demand is often 80%
of the total, an amount of “dark energy” hidden from view, discovered by finding the
average energy estimated needs for businesses far below the world average energy
consumed per dollar of GDP. Presently for lack of information the energy needs of
business services are counted to be “0”. Our default assumption is to treat them as
“average”. The result is a hard measure of total business demand for energy services, a
“Scope 4” energy use or GHG impact assessment. Counting recorded energy uses and
discounting unrecorded ones misrepresents labor intensive work as highly energy efficient.
The result confirms a similar finding by Hall et al. in 1981 [1]. We use exhaustive search
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Reprinted fromSustainability. Cite as: Henshaw, P.F.; King, C.; Zarnikau, J. System Energy Assessment
(SEA), Defining a Standard Measure of EROI for Energy Businesses as Whole Systems.Sustainability
2011 , 3 , 1908-1943; doi:10.3390/su3101908.