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Figure 10. The (a) Annual Business Energy Flow and (b) Cumulative Business Energy
Flow (kWh/kW) for each SEA level. The SEA4.2 (PTC) level is shown as if the tax credit
was an energy gain to the business, though no energy is saved by it, showing one way
common financial assumptions.- Interpretation, Application and Future Work
4.1. Whole System Comparative Value
To compare the energy productivity of our wind farm business model with other businesses, we use
the world average GDP produced per unit of energy to define a new benchmark, monetary return on
energy invested (MREI), measuring the income produced per unit of energy used (Equation 11).
MREI = Revenue / Energy Cost (11)
The world average economic value added for energy use is 1/EiW (see Equation 1 and 2). In Figure
11 bar-2 (100%) & bar-3 (95%) show, respectively, the world average revenue produced for the SEA4
level of energy use compared to the estimated revenue of the wind farm, estimated at SEA4 to for 11%
net revenue after costs and taxes. For general comparison bar-1(85%) shows the total expenditures at
SEA4 and bar-4 (143%) shows an artificial “retail value” as if the wholesale price were marked up
50%. The wholesale MREI value for the electricity generated by the wind farm seems to be 5% below
the world average for using that same amount of energy.
The Costanza data (Figure 1) indicated that businesses in the energy sector generally produce
significantly higher than average economic value for the energy used (i.e., lower than average energy
intensity for the value added). Some of the model assumptions that might be changed to show the wind
farm producing more economic value for the energy are (1) lowering the Eii value of 150% of average
for the technology costs, (2) raising the estimated wholesale market price of electricity from $83/MWh
to show a greater profit margin than 11%, (3) raising the rate of wind utilization from the estimated
capacity factor of 33%, and (4) distributing the capital costs over more years. It might also indicate
that the estimated US combined tax rate of 36% on net revenue is higher than the world average. That