irradiance: loading…
Solar array
1800 W
4 × 450 W panels
Battery bank
19.2 kWh
8 × 12V 200Ah · 2-day autonomy
Charge controller
50 A
MPPT at 48 V
Inverter
1400 W
pure sine
Daily load
5610 Wh
worst sun 5 h (Jul)
Main DC wire
8 AWG
~37.5 A run
Monthly peak sun hours · worst month drives the array
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Loads · edit and watch the system resize
| Load | Watts | Qty | Hours/day | Wh/day |
|---|---|---|---|---|
| LED classroom lights | 1080 | |||
| Timeback tablets (charging) | 800 | |||
| Starlink dish + router | 750 | |||
| Laptop chargers | 1040 | |||
| Water pump | 500 | |||
| Vaccine/medicine fridge | 1440 |
Bill of materials
- 4 solar panels1800 W
- 8 batteries (12V 200Ah LiFePO4)19200 Wh
- MPPT charge controller≥ 50 A
- Pure-sine inverter≥ 1400 W
- Main DC conductor8 AWG
- Balance of systembreakers, fuses, combiner, grounding
How it works
Pulls the site's solar irradiance from NASA POWER, derates for real-world losses and battery depth-of-discharge, then sizes panels, battery bank, charge controller, inverter, and wiring to carry the school through its worst month plus days of autonomy.
What's real
- ✓Live NASA POWER irradiance (no API key), cached so it sizes offline once a site has been seen online
- ✓Genuine engineering math: derate, Peukert depth-of-discharge, autonomy, wire-gauge bands
- ✓Editable load list — change a load and the whole bill of materials resizes
Demo limits — honest about it
- ○Component specs and prices are representative catalog values, not live supplier quotes
In the field
Loita Hills, Kenya runs classroom lights, Timeback tablets, a water pump, and a vaccine fridge on a 48V bank with 2 days of autonomy.
Stack
NASA POWER APITypeScript sizing engineVitest-testedRuns offline