Which Appliances Are Costing You the Most?
Think in kWh, not watts
Watts tell you how powerful an appliance is. What matters for your bill is kilowatt-hours (kWh) — watts multiplied by hours of use, divided by 1000.
A 2000W electric oven running for 1 hour uses 2 kWh. At €0.30/kWh, that's €0.60 per use — around €18 per month if used daily. Not dramatic in isolation, but it adds up across a full household.
The usual suspects
Refrigerators run 24 hours a day, every day. A 150W fridge uses 108 kWh per month — one of the biggest single contributors to most household bills, even though it draws relatively little power per hour.
Electric ovens and hobs draw 1500–2500W and are often used daily. They're among the most controllable costs — batch cooking or using a microwave for reheating can meaningfully reduce usage.
Washing machines pull 1500–2500W during a cycle. The hot water heating is the main cost driver. Washing at 30°C instead of 60°C uses roughly 60% less energy per cycle.
Air conditioners are peak consumers at 1000–3500W. A single hot-weather month running AC for 8 hours a day can add €40–80 to a bill.
EV chargers are a special case — a 7kW home charger running for 6 hours adds 42 kWh per session. For daily drivers, this can easily double a household's electricity usage.
Low-draw devices that run constantly
Don't ignore standby power. TVs, game consoles, routers, and smart home devices all draw small but continuous amounts. A device drawing just 5W in standby uses 3.6 kWh per month — multiply that across 10 devices and it's 36 kWh, roughly €10/month for nothing.
Smart plugs with scheduling can eliminate standby waste on devices that don't need to be always-on.
Solar: when does it make sense?
A typical 3 kW residential solar installation produces around 300 kWh per month in central Europe — enough to cover a significant portion of average household consumption.
The payback period varies by location, installation cost, and how much of the solar generation you consume directly (vs. exporting). In most of Europe, payback periods are now 6–10 years, with panels lasting 25+ years.
The Good Patrone Electricity Bill Estimator shows what percentage of your current monthly usage a 3 kW system could cover — a useful first sanity check before getting quotes.
A simple audit process
- List every appliance that draws significant power
- Estimate realistic hours of daily use
- Calculate monthly kWh (watts × hours × 30 ÷ 1000)
- Multiply by your rate per kWh
This gives you a ranked list of where your money is going — and where switching habits or upgrading equipment will have the most impact.