日常

Solar Panel Payback Calculator

When does your solar system pay off? Enter installation cost, output, self-consumption rate and feed-in tariff – the calculator shows you the break-even point and total savings over 20 years in seconds.

✓ 監修 Julian Bronski · 更新 2026年6月

入力項目

国 / 通貨

▾

Installation cost JPY 15.000

JPY

1000200000+

System size 10

kWp

1100+

Annual yield per kWp 900

kWh

5001400+

Self-consumption rate 30%

0100+

Electricity price (per kWh) JPY 0,32

JPY

0.051.5+

Feed-in tariff (per kWh) JPY 0,08

JPY

00.5+

計算結果

Break-even (years)

–

Annual return (€)

–

Total savings over 20 years

–

✓ コピーしました!

この計算機をサイトに埋め込む ▾

無料で利用できます。コードをコピーしてページに貼り付けるだけで動作します。

<iframe src="https://kalkulio.app/ja/solar-panel-payback-calculator/embed/" style="width:100%;max-width:720px;height:940px;border:0;border-radius:16px;background:#faf9f4" title="Solar Panel Payback Calculator" loading="lazy"></iframe>
<p style="margin:6px 0 0;font-size:13px"><a href="https://kalkulio.app/ja/solar-panel-payback-calculator/" target="_blank">Solar Panel Payback Calculator — 無料 – kalkulio.app</a></p>

Solar Panel Payback Calculatorのしくみ

Annual yield (kWh) = kWp × yield/kWp. Of this, self-consumption % goes directly to the household (saving = kWh × electricity price), the rest is exported (income = kWh × feed-in tariff). Break-even = cost ÷ annual return (€).

よくある質問

What is a typical annual yield? ▾

In Central Europe, yield ranges from 800–1,100 kWh per kWp depending on location. Southern regions get more sun; northern areas typically yield 850–950 kWh/kWp.

What feed-in tariff should I enter? ▾

Feed-in tariffs vary by country: Germany ~8 ct/kWh (EEG 2024), Austria ~8–10 ct/kWh, Switzerland varies by canton. Check your local energy provider for the current rate.

How do I increase self-consumption? ▾

Without a battery, self-consumption is typically 25–35%. Adding a home battery storage system raises it to 60–80%, dramatically improving returns since electricity costs (€0.30+/kWh) far exceed feed-in rates.

How much does a 10 kWp system cost? ▾

In Germany, a 10 kWp system currently costs around €12,000–18,000 including installation. With a battery storage system (€8,000–12,000 extra), costs rise but so does self-consumption.

Solar Panel Payback Calculatorのしくみ

よくある質問

ほかの計算機

EV Charging Cost Calculator

ガソリン代計算機

Inflation Calculator