您可以使用 TypeScript 建立自己的計算。你可以透過本頁底部的程式碼，判斷安裝太陽能板 (安裝太陽能板或依原樣支付) 長期費用是否較低。
以下概略說明這個程式碼如何決定太陽能板費用。
第 1 部分：系統需求與設定
首先，確定目前的電力用量和帳單費用：
- 你每月會使用多少電力？(
monthlyKwhEnergyConsumption) - 那麼電用多少錢？(
energyCostPerKwh)
接著，請輸入您的太陽能系統方案：
- 要設多少面板？(
panelsCount) - 面板的功能有多強大？(
panelCapacityWatts) - 安裝費用是多少？(
installationCostPerWatt) - 系統是否適用折扣？(
solarIncentives)
第 2 部分：計算
這個程式碼會根據輸入的值計算：
yearlyProductionAcKwh：太陽能板可產生的年度總電力。totalCostWithSolar：太陽能板「固定」多年來的電力成本。totalCostWithoutSolar：未採用太陽能板「未」的多年電力成本。
第 3 部分：結果
程式碼也會提供以下資訊：
savings：使用和不含太陽能板的成本差異。breakEvenYear：直到太陽能板費用等於用電節省的年數。
程式碼範例
// Solar configuration, from buildingInsights.solarPotential.solarPanelConfigs
let panelsCount = 20;
let yearlyEnergyDcKwh = 12000;
// Basic settings
let monthlyAverageEnergyBill: number = 300;
let energyCostPerKwh = 0.31;
let panelCapacityWatts = 400;
let solarIncentives: number = 7000;
let installationCostPerWatt: number = 4.0;
let installationLifeSpan: number = 20;
// Advanced settings
let dcToAcDerate = 0.85;
let efficiencyDepreciationFactor = 0.995;
let costIncreaseFactor = 1.022;
let discountRate = 1.04;
// Solar installation
let installationSizeKw: number = (panelsCount * panelCapacityWatts) / 1000;
let installationCostTotal: number = installationCostPerWatt * installationSizeKw * 1000;
// Energy consumption
let monthlyKwhEnergyConsumption: number = monthlyAverageEnergyBill / energyCostPerKwh;
let yearlyKwhEnergyConsumption: number = monthlyKwhEnergyConsumption * 12;
// Energy produced for installation life span
let initialAcKwhPerYear: number = yearlyEnergyDcKwh * dcToAcDerate;
let yearlyProductionAcKwh: number[] = [...Array(installationLifeSpan).keys()].map(
(year) => initialAcKwhPerYear * efficiencyDepreciationFactor ** year,
);
// Cost with solar for installation life span
let yearlyUtilityBillEstimates: number[] = yearlyProductionAcKwh.map(
(yearlyKwhEnergyProduced, year) => {
const billEnergyKwh = yearlyKwhEnergyConsumption - yearlyKwhEnergyProduced;
const billEstimate =
(billEnergyKwh * energyCostPerKwh * costIncreaseFactor ** year) / discountRate ** year;
return Math.max(billEstimate, 0); // bill cannot be negative
},
);
let remainingLifetimeUtilityBill: number = yearlyUtilityBillEstimates.reduce((x, y) => x + y, 0);
let totalCostWithSolar: number =
installationCostTotal + remainingLifetimeUtilityBill - solarIncentives;
console.log(`Cost with solar: $${totalCostWithSolar.toFixed(2)}`);
// Cost without solar for installation life span
let yearlyCostWithoutSolar: number[] = [...Array(installationLifeSpan).keys()].map(
(year) => (monthlyAverageEnergyBill * 12 * costIncreaseFactor ** year) / discountRate ** year,
);
let totalCostWithoutSolar: number = yearlyCostWithoutSolar.reduce((x, y) => x + y, 0);
console.log(`Cost without solar: $${totalCostWithoutSolar.toFixed(2)}`);
// Savings with solar for installation life span
let savings: number = totalCostWithoutSolar - totalCostWithSolar;
console.log(`Savings: $${savings.toFixed(2)} in ${installationLifeSpan} years`);