The BIPV Energy Yield API delivers research-grade energy yield, financial analysis, and environmental impact calculations for building-integrated photovoltaic (BIPV) systems — covering facades, curtain walls, ventilated cladding, and roof-integrated panels.
Developed by a structural engineering researcher specialising in BIPV, this API was built to address a specific gap in the market: most solar energy calculators treat a facade-mounted panel identically to a rooftop panel. They ignore the thermal penalties of building integration, apply generic climate averages instead of site-specific irradiance data, and add loss factors with no published basis. The difference between a generic calculation and a research-grounded one can exceed 25% on the same system — enough to determine whether a project is financially viable or not.
Every model in this API is implemented directly from its original peer-reviewed publication. The irradiance transposition model follows Reindl, Beckman & Duffie (1990). Cell temperature is calculated using the Sandia model (King et al. SAND2004-3535), validated specifically for BIPV facades by Martín-Chivelet et al. (2022). Integration losses follow the IEA PVPS Task 15 (2018) framework — the only internationally recognised standard built specifically for BIPV systems. Financial analysis applies the LCOE methodology from IRENA (2023) with degradation modelled per Jordan & Kurtz (2013).
Irradiance data is pulled in real time from NASA POWER MERRA-2 — 22-year climatological averages at 0.5° × 0.625° resolution for any GPS coordinate on Earth. This replaces climate-zone approximations with satellite-verified site data.
A single API call returns annual and monthly energy yield, Performance Ratio per IEC 61724-1:2021, LCOE, NPV, IRR, 25-year cashflow profile, CO₂ savings, carbon payback period, and a full loss breakdown across glass optical, thermal, ventilation, wiring, and system losses.
Used by architects, facade engineers, EPC contractors, energy consultants, and sustainability teams who need numbers they can defend in a technical report or investment proposal.
Standards applied: IEC 61215:2021 · IEC 61724-1:2021 · EN 50583-2:2016 · IEA PVPS Task 15 · IRENA 2023.
Free tier available for testing. Pro plan at $49/month includes NASA POWER real irradiance data and full financial analysis.