Solar System & Battery Sizing for 1,125 kWh/Month in Hawaii, USA
Complete photovoltaic engineering breakdown for a 1,125 kWh/month (37.5 kWh/day) electricity profile in Hawaii, USA (5.8 Peak Sun Hours/day).
Technical Specification Table — 1,125 kWh/Month Solar System (Hawaii, USA)
| Monthly / Daily Electricity Consumption | 1,125 kWh/month (37.5 kWh/day) |
| Location Peak Sun Hours (PSH) | 5.8 hours/day (Hawaii, USA) |
| Required PV System Size (80% Performance Ratio) | 8.36 kWp DC |
| Number of Solar Panels (440W N-Type Bifacial) | 19 panels |
| Roof Area Required | 38.9 m² (419 sq ft) |
| Recommended Hybrid Inverter Rating | 7.5 kW AC |
| Recommended LiFePO4 Battery Storage (85% DoD) | 28.7 kWh Nominal (24.4 kWh Usable) |
| Estimated Annual Output | 14,158 kWh/year (~1,180 kWh/month) |
| Estimated System Turnkey Cost (Before Tax Credits) | $25,916 |
| Annual Electricity Bill Savings (@ $0.42/kWh) | $5,946/year ($496/month) |
Frequently Asked Questions
How many solar panels are needed for 1,125 kWh per month in Hawaii, USA?
With an average of 5.8 Peak Sun Hours per day in Hawaii, USA and an 80% system performance ratio, a monthly usage of 1,125 kWh (37.5 kWh/day) requires a 8.36 kWp solar array, which equals 19 standard 440W N-Type solar panels occupying 38.9 m² (419 sq ft) of roof space.
What size solar battery bank do I need for 1,125 kWh/month?
To cover evening and overnight loads (65% of daily consumption at 85% LiFePO4 depth of discharge), a 28.7 kWh nominal (24.4 kWh usable) LiFePO4 battery bank paired with a 7.5 kW hybrid inverter is recommended.
How much money will a 8.36 kW solar system save in Hawaii, USA?
Generating approximately 14,158 kWh per year at an average local tariff of $0.42/kWh, the system saves $5,946 per year ($496/month) with an estimated payback period of 4.4 years.