Validated method for sizing standalone PV systems using peak sun hours with TRNSYS simulation (45 citations).
Based on the paper's peak sun hour methodology with TRNSYS validation. System efficiency: 75%, 2-day autonomy, 50% depth of discharge.
Sizing standalone PV systems traditionally requires complex hourly simulation software that demands significant computational resources and meteorological data. Tools like TRNSYS need detailed inputs: hourly irradiance, temperature profiles, wind speed data, and component specifications.
For residential installers and off-grid designers in developing regions, this creates a barrier to adoption. The software is expensive, the learning curve is steep, and the required meteorological data may not be available for remote locations.
The peak sun hour method offers a simpler approach but, prior to this paper, lacked validation against industry-standard transient simulation tools like TRNSYS. This gap left practitioners uncertain about whether simplified sizing was reliable enough for real installations.
The paper presents a sizing methodology that uses peak sun hours, defined as the equivalent hours of 1000 W/m² irradiance, to determine photovoltaic panel and battery capacity. Sigit developed the mathematical models and performed TRNSYS 16.0 hourly time-step transient simulations to validate the simplified method.
The system was tested for a typical Malaysian terraced house with 6 kWh daily energy consumption. The methodology compares peak sun hour estimates against detailed simulation results, using a 75% system efficiency factor and 2-day battery autonomy.
The validation loop runs TRNSYS simulations with location-specific weather data, comparing monthly energy production between the simplified PSH estimate and the full hourly simulation. Error margins are calculated to determine whether the simplified method is adequate for residential design purposes.
The peak sun hour method demonstrated close agreement with TRNSYS simulation results for the Malaysian test case. Monthly energy production predictions fell within 2-4% error of the hourly simulation output across all twelve months.
The validation confirmed that the simplified method can reliably size standalone systems for tropical climates where solar resource variation follows predictable patterns. The error margins were within acceptable limits for residential design purposes, where 5% sizing error does not significantly impact system performance or cost.
The method assumes consistent tropical solar patterns and may require adjustment for high-latitude locations with significant seasonal variation. The validation was conducted at a single tropical site (Kuala Lumpur), and performance at other latitudes has not been empirically verified.
Future work could extend validation to different climate zones, integrate battery aging models into the sizing calculations, and develop simplified adjustment factors for temperate and high-latitude locations. A mobile application implementing the calculator for field use would increase accessibility for rural installers.
International Journal of Renewable Energy Research (IJRER), 2022
DOI: 10.20508/ijrer.v4i1.1026
Uses peak sun hour methodology for sizing off-grid solar in Pasuruan, East Java.
Applies the same sizing principles to rural electrification in Indonesia.
Provides the solar measurement foundation for the peak sun hour methodology.
This foundational sizing methodology underpins several of sigit's subsequent applied projects in rural electrification and off-grid solar system design.