Published Paper Details:

Solar Rooftop PV systems are becoming more popular these days as it is proven to lower electricity bills and potential contributory to lessen CO2 emissions. Three models of 1.215 kWp solar rooftop PV systems, namely: on-grid, off-grid and hybrid were designed and installed at Room EB217 of the College of Engineering building, Tarlac State University, Romulo Boulevard San Vicente, Tarlac City in order to determine their individual characteristics in terms of (1) design analysis and wiring diagram; (2) solar PV System components and total cost of installations; (3) amount of savings incurred in the solar generation and (4) rate of return and recovery period. The result showed that for the same amount of solar panel capacity, the on-grid model has the simplest design and wiring diagram as compared to the off-grid and hybrid models. Also, the on-grid model has the least number of components and no battery and thereby it is the most economical model to install since it is 58% cheaper than the two other models. In terms of actual amount of savings incurred in the solar generation, the hybrid model offers the highest savings of P2,798.40 per month, followed by the on-grid model at P2,126.40 per month while the off-grid model had the lowest monthly savings of P1,017.60 per month. Among the three models, the on-grid offers the highest ROR on investment at 2.72% per month and the shortest period of recovery of 3 years. The hybrid had an ROR of 2.08% per month and a recovery period of 4 years while the off grid had the lowest ROR of 0.75% per month and the longest recovery period of 11 years. It is concluded that the on-grid model offers the most feasible and viable alternative in solar rooftop PV system design and installations.