5 Energy Return
5.1 EROEI
Tverberg
“Energy Return on Energy Investment” (EROEI) pertains to direct use of energy, rather than energy embodied in added complexity. As a result, EROEI indications tend to suggest that innovations such as wind turbines, solar panels and EVs are more helpful than they really are. Other measures similar to EROEI make a similar mistake.
Energy needs are hidden in many areas. For example, to have a complex system, we need a financial system. The cost of this system cannot be added back in. We need modern roads and a system of laws. The cost of a government providing these services cannot be easily discerned. An increasingly complex system needs education to support it, but this cost is also hard to measure. Also, as we note elsewhere, having double systems adds other costs that are hard to measure or predict.
Wind and solar generation need complexity to fix their intermittency problems.
Complexity has an energy cost, but this cost is virtually impossible to measure.
if the available energy supply is reduced, the system will need to simplify. Simplification usually doesn’t happen voluntarily.
It is easy for EROEI calculations (and similar calculations) to overstate the benefit of complex types of energy supply.
EROEI calculations consider only direct “energy investment” costs. For example, the calculations are not designed to collect information regarding the higher energy cost of a dual system, with parts of the system under-utilized for portions of the year. Annual costs will not necessarily be reduced proportionately.