Association for Public Policy Analysis & Management

Sustained U.S. solar photovoltaic (PV) demand and supply-side policies, in concert with efforts across the world, have led to significant improvements in the cost of solar PV hardware. As a result, the installed cost of solar PV has declined. Recently, attention has turned to non-hardware “soft” costs, which have remained stubbornly high, and now makeup a disproportionately high share of residential solar PV costs compared to a decade ago. Until recently, soft costs, including customer acquisition, design and siting, operations, finance, and installation labor, have been an afterthought in the effort to bring to bear renewable energy solutions and, as a result, little agreement exists across sectors and amongst scholars.

In this paper we develop an original ontology, systematically and semantically organizing the soft cost knowledge domain. The ontology, developed using concepts from more than 185 relevant studies and market reports, illustrates the relationships behind solar sector soft costs, the actors engaged in the soft cost ecosystem, and the interactions, knowledge flows and learning processes that ultimately influence soft costs. The result is a first-of-kind comprehensive overview of the solar sector’s non-hardware ecosystem.

The ontology is the ground-level building block for a large, multiyear research endeavor, exploring soft cost drivers, and the state of learning mechanisms that need to be addressed for soft costs to fall. This paper also introduces how the ontology has been used directly 1) to improve the integrity of a national survey of installation firms and 2) validate understanding of firm-level processes through case study research.