Solar cells can be built directly into the things around us, but they generally aren’t. Is it a missed opportunity?
In the early days of photovoltaic (PV) research, a mainstream opinion envisioned the future of PV as building-integrated and that utility-scale installations would be anomalies. As an example, in 1994, PowerLight introduced a solar roofing tile system, touting it as saving money (avoiding the cost of installing a conventional roof) while integrating PV into an attractive roof. However, today, utility-scale PV accounts for more than half of the world’s PV installations, and building-integrated PV (BIPV) is a niche market (with most rooftop systems being “building-applied” rather than “building-integrated”). This motivates the question: “Was integrating PV into the desired product a bad idea or is it an idea whose time has not yet come?” Many things have changed since the 1990s including microinverters and other power electronics, PV with lower temperature coefficients, and demonstration of PV as an accepted technology so that it is not such a risk to builders, potentially giving a fresh opportunity. In this article, we explore the potential value of integrating PV into surfaces and the challenges to achieving that value.