An Assessment of Civil Nuclear ‘Enabling’ and ‘Amelioration’ Factors for EROI Analysis

Nuclear fission is a primary energy source that may be important to future efforts to reduce greenhouse gas emissions. The energy return on investment (EROI) of any energy source is important because aggregate global EROI must be maintained at a minimum level to support complex global systems. Previous studies considering nuclear EROI have emphasised energy investments linked to ‘enabling’ factors (upstream activities that enable the operation of nuclear technology such as fuel enrichment), have attracted controversy, and challenges also persist regarding system boundary definition. This study advocates that improved consideration of ‘amelioration’ factors (downstream activities that remediate nuclear externalities such as decommissioning), is an important task for calculating a realistic nuclear EROI. Components of the ‘nuclear system’ were analysed and energy investment for five representative ‘amelioration’ factors calculated. These ‘first approximation’ calculations made numerous assumptions, exclusions, and simplifications, but accounted for a greater level of detail than had previously been attempted. The amelioration energy costs were found to be approximately 1.5–2 orders of magnitude lower than representative ‘enabling’ costs. Future refinement of the ‘amelioration’ factors may indicate that they are of greater significance, and may also have characteristics making them systemically significant, notably in terms of timing in relation to future global EROI declines.