This chapter describes the assumptions based on the case study, followed by the methods employed, consisting of three main activities: data acquisition, RSPP design, and design result analysis. The analyses in each activity are done using codes written in MATLAB.
Case study
The Ontowiryo Mosque is located at 109.96° Longitude, −7.85° Latitude, in Wonosari village, Ngombol subdistrict, at the south side of Purworejo district, Central Java. The configuration of the roof, azimuth, tilt, and area, is presented in Fig. 1 and Table 1. The mosque is connected to the grid with a maximum electricity capacity of 5,500 VA. As a community center, installing RSPP on the mosque further enhances its purpose, such as providing street lighting to its surroundings, given the lack of such service in the neighborhood of the case study. This purpose is of interest for further studies as the RSPP analyzed in this paper is limited to supplying the energy use in the mosque, described in the following section.
Figure 1
(a) Indoesia Map showing the location of the Ontowiryo Mosque, modoified from FreeVectorFlags.com with CorelDRAW 201841,42, (b) Google maps image showing the mosque that is facing south-west. The mosque roof has two sides, west (W) and east (E). Image is modified with CorelDRAW 201842, (c) The South Façade adapted from the mosque’s Detailed Engineering Design43.
Table 1 Ontowiryo Mosque roof configuration.
Data acquisition
The data acquisition process prepares the required data for the RSPP design process, including site condition data and hourly electricity load profile data. The site condition data are obtained from Solcast, which provides a comprehensive set of hourly site condition data44. This data includes air temperature, cloud opacity, Diffuse Horizontal Irradiance (DHI), Direct Normal Irradiance (DNI), Global Horizontal Irradiance (GHI), sun azimuth angle, sun altitude angle, wind speed, relative humidity, and precipitable water. Site condition data are available for the chosen location for 12 years (2008–2019) or 4,383 days, containing 105,192 hourly data.
Figure 2a shows the average daily GHI across 12 years of data with a relatively constant value with an average of 5.4 kW/m2 per day. The slight fluctuation is due to the seasonal difference between years, where one year may have a longer dry/wet season and vice versa. The dry season in Indonesia spans in the middle of the year, while the rest is the wet season. Figure 2b presents the variation of irradiances throughout the year. GHI is relatively constant, while higher DHI values are observed at the end and beginning of the year. This condition is due to the wet season with more frequent rain and cloudy skies. Due to the relatively constant irradiance value across years, the site condition data used in the design and simulation can …….