How to Build a Off Grid Generator

function sizeOffGridSystem(loads, location) {
  const { peakSunHours, daysAutonomy = 3, systemVoltage = 48 } = location;
  const derateFactor = 0.80;

  // Step 1: Calculate daily energy consumption
  const dailyKwh = loads.reduce((sum, load) => {
    return sum + (load.watts * load.hoursPerDay) / 1000;
  }, 0);

  // Step 2: Size solar array
  const solarWatts = Math.ceil((dailyKwh * 1000) / (peakSunHours * derateFactor));

  // Step 3: Size battery bank (LiFePO4 at 80% DoD)
  const batteryDoD = 0.80; // LiFePO4; use 0.50 for lead-acid
  const batteryAh = Math.ceil(
    (dailyKwh * daysAutonomy * 1000) / (systemVoltage * batteryDoD)
  );
  const batteryKwh = (batteryAh * systemVoltage) / 1000;

  // Step 4: Size charge controller
  const chargeControllerAmps = Math.ceil((solarWatts / systemVoltage) * 1.25);

  // Step 5: Size inverter
  const peakWatts = loads.reduce((max, load) => max + load.watts, 0);
  const inverterWatts = Math.ceil(peakWatts * 1.25);

  return {
    dailyKwh: Math.round(dailyKwh * 100) / 100,
    solarArrayWatts: solarWatts,
    solarPanels: Math.ceil(solarWatts / 400), // assuming 400W panels
    batteryBankAh: batteryAh,
    batteryBankKwh: Math.round(batteryKwh * 100) / 100,
    chargeControllerAmps,
    inverterWatts,
    systemVoltage
  };
  }

  // Example: cabin with basic loads
  const cabinLoads = [
  { name: 'LED Lights', watts: 100, hoursPerDay: 6 },
  { name: 'Refrigerator', watts: 150, hoursPerDay: 8 },
  { name: 'Laptop', watts: 65, hoursPerDay: 4 },
  { name: 'Water Pump', watts: 500, hoursPerDay: 1 },
  { name: 'Router', watts: 12, hoursPerDay: 24 }
  ];
  // peakSunHours: check PVWatts for your location (e.g., 4.5 in Pacific NW, 6.5 in Arizona)