Solar Plan Lab grew from a practical Philippine DIY solar project: rising electricity costs, intimidating installer packages, configuration faults, and the need for transparent calculations that ordinary homeowners can understand.
The public tools are shaped by what actually became difficult: estimating load, checking component limits, understanding source priority, sizing storage, measuring the house, and planning expansion without replacing everything.
Read the detailed case study →Air conditioning ran through the night for work and during the day for sleep. After a second air conditioner was added, the monthly electricity bill rose from roughly ₱11,000 to about ₱14,500–₱15,500. The initial load estimate was about 16.5 kWh/day, but a Wi-Fi energy meter later showed consumption closer to 21 kWh/day.
Installer labour, commissioning, warranty, and accountability have real value. The problem is when a quotation hides component models, undersizes storage, or prevents the homeowner from understanding how the system works. The project therefore used an itemised, phased approach: buy one working stage, measure it, fix the faults, then expand.
The inverter and battery did not communicate until the correct lithium protocol and RS485 mode were selected. Solar Plan Lab now treats communication protocol as a compatibility field instead of assuming that matching voltage is enough.
A grid-charging mode caused repeated source switching as battery voltage moved around the transfer thresholds. Changing the operating strategy to solar-only charging stopped the loop. Solar Plan Lab therefore separates energy-source priority, grid charging, and ATS behaviour in its schematic guidance.
A conservative cutoff stranded usable battery capacity and produced warnings before the pack was meaningfully depleted. The correct value is product-specific: final thresholds must follow the battery, BMS, inverter documentation, and measured cell behaviour—not a universal internet setting.
These figures are historical reference costs for the documented build, not a universal quotation.
Mounting structure, labour, delivery, permits, structural work, and later expansion are excluded unless separately entered.
Confirm inverter settings, source transfer, monitoring, and real daily energy demand.
Add compatible batteries only after measured night-time demand and BMS current requirements are understood.
Recalculate series voltage, MPPT range, current, cable, protection, and roof fit before adding panels.
Run a sustained test with utility power retained as backup before calling the system independent.
Solar Plan Lab does not replace an electrician, structural engineer, manufacturer manual, or site inspection. It gives homeowners a clearer starting point, exposes assumptions, and makes it harder for a design mismatch to stay hidden.