Valuing Sustainability of Adaptable Infrastructure Using ROA-SEC: A Hybrid Approach

Abstract

Infrastructure providing fundamental services for societies may become obsolete under changing environments such as climate or demographics changes, creating the need for adaptability. Designing infrastructure for adaptability may affect life cycle costs as well as environmental and social issues such as resources consumption, waste production or disruption to services provided. Sustainability valuation of adaptable infrastructure is thus required. The Real Options Analysis (ROA) is widely used to evaluate financial viability of investing in adaptable infrastructure. But, the environmental and social aspects have been barely noticed and incorporated. Hence, a valuation method is required to properly address all aspects of sustainability. This paper bridges the gap and advances the literature by presenting a methodology for designed-in adaptability valuation, considering all the sustainability aspects. To this end, a hybrid approach is suggested through integration of Social and Environmental Costing (SEC) with ROA, providing a single measure for sustainability of adaptable infrastructure. In this approach, the outputs of Life Cycle Assessment (LCA) tools are monetized using SEC methods; and then incorporated in the ROA that is built on the probabilistic Discounted Cash Flow (DCF) analysis, suitable for engineering applications. The application of the proposed approach is illustrated on a case example involving seawalls under changing climate effects. For the case example, including sustainability issues in the analysis improved the viability of designing in adaptability. This conclusion cannot be generalized and each situation requires an individual analysis. However, the proposed approach and methodology will be the same in all the situations.