Mitigation of atmospheric carbon emissions through increased energy efficiency versus increased non-carbon energy sources: A trade study using a simplified (open quotes)market-free(close quotes) exogenously driven model

摘要

A simplified model of global, long-term energy use is described and used to make a 'top-level' comparison of two generic approaches for mitigating atmospheric carbon emissions: (a) those based on increased energy efficiency; and (b) those based on increased use of reduced- or non-carbon fuels. As approximate as is the model, first-order estimates of and trade offs between increasing non-carbon generation capacities (e.g., supply-side solutions) versus energy-use efficiency (e.g., demand-side solutions) to stem atmospheric carbon accumulations can be useful in guiding more elaborate models. At the level of this analysis, both the costs of abatement and the costs of damage can be large, with the formation of benefit-to-cost ratios as a means of assessment being limited by uncertainties associated with relating given climatic responses to greenhouse warming to aggregate damage cost, as well as uncertainties associated with procedures used for multi-generation discounting of both abatement and damage costs. In view of uncertainties associated with both supply-side and demand-side approaches, as well as the estimation of greenhouse-warming responses per se, a combination of solutions seems prudent. Key findings are: (a) the relative insensitivity of the benefit-to-cost ratio adopted in this study to supply-side versus demand-side approaches to abating atmospheric carbon-dioxide emissions; (b) the extreme sensitivity of damage costs, abatement costs, and the related benefit-to-cost ratios to the combination of discounting procedure and the (time) concavity of the function used to relate global temperature rise to damage costs; and (c) no matter the discounting procedure and/or functional relationship between average temperature rise and a damage cost, a goal of increased per-capita gross world product at minimum damage suggests action now rather than delay.