您可以使用 TypeScript 建立自己的運算作業。本頁底部的程式碼可協助您判斷長期而言，安裝太陽能板是否比繼續支付電費更便宜。
以下是程式碼如何判斷太陽能板費用的概略說明。
第 1 部分：系統需求和設定
首先，請定義目前的電費使用量和帳單：
- 你每個月的用電量為何？(
monthlyKwhEnergyConsumption) - 電費多少？(
energyCostPerKwh)
接著，輸入太陽能系統的計畫：
- 有幾個面板？(
panelsCount) - 面板的效能有多強？(
panelCapacityWatts) - 安裝費用是多少？(
installationCostPerWatt) - 系統是否有折扣？(
solarIncentives)
第 2 部分：計算
根據輸入的值，程式碼會計算：
yearlyProductionAcKwh：太陽能板每年可產生的總電量。totalCostWithSolar：使用太陽能板的電費。totalCostWithoutSolar：不使用太陽能板的電費。
第 3 部分：結果
程式碼也會告知您以下資訊：
savings：安裝/未安裝太陽能面板的費用差異。breakEvenYear：太陽能板的成本與省下的電費相等，需要多久時間？
範例程式碼
// 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`);