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test value for using the Option 3 method of avoiding double count. On later examination it was
discovered that the same answer would result if we treated TE and EE values as entirely separate (using
the Option 2 method), using Eii = 0.9 to represent only the untraceable economic energy for the supply
chain business operations for the LCAE technology package. The Eii of 0.9 was estimated by taking
the energy use totals from all the economic sectors provided by Costanza [12] that seemed associated
with the least traceable energy uses for operating businesses, as a share of the total, around 90%. That
avoids the potential of double counting by having a complete estimate of the traceable technology
energy use, and an intensity factor scaled to estimate only the untraceable economic energy uses.
Figures 6 and 7 show the fractions of additional energy use accounted for and the corresponding
fractional reductions in EROI. The technology energy use (LCAE) accounts for 19.1% of the total, and
the value of EROI that starts at 31:1 declines by 81% to 6:1 by SEA4. In Figure 7 you see EROI
decreasing by smaller proportional steps from SEA0 to SEA3, but then at SEA4 decreasing by a larger
step again, for the large environmental costs of financing and taxes. Figure 8 shows the estimates of
the LCOE breakeven price for the electricity, rising from approximately $.002/kWh at LCAE to
$.076/kWh at SEA4. LCOE is shown for the partial cost estimates at each level, just as the partial
estimates of EROI were based on partial assessments of the energy needed at each system operating
level. We find that the LCOE substantially rises and EROI declines as we consider more of the
business operations needed. The curves have different shapes because there is more energy per dollar
embedded in the LCAE and SEA0 business costs.
Figure 6. Annualized estimates of 20 yr energy uses, amounts added at each scale of
business working unit, LCAE to dSEA4. Accounting for all internal costs at dSEA3 and
adding environmental costs at dSEA4.