Last updated: August 2026
What actually uses the electricity in an Irish home? Most people guess wrong: the phone chargers and standby lights everyone worries about cost cents, while the immersion, tumble dryer and electric shower quietly do the damage (a dehumidifier dries a load of washing for a fraction of the dryer's cost). At a typical standard rate of around 33-35c per kWh, every appliance has a knowable price per use - and once you know the handful of big ones, you know exactly where your bill comes from. Here is the honest league table, what each appliance costs per use, and the shifts that cut real money without a single cold shower.
⚡ Quick Summary
🌿 The big five: immersion, electric shower, tumble dryer, oven and dishwasher - heat is expensive, electronics are cheap.
🌿 Rules of thumb: anything that heats costs euros; anything that computes or glows costs cents.
🌿 A 3kW immersion left on for an hour ≈ €1; an evening of TV ≈ 5-10c.
🌿 Night rate halves it or better: on a smart tariff, running the dishwasher, washing machine and dryer after 11pm cuts those units to roughly a third of peak price.
🌿 Peak warning: 5-7pm is the dearest window on smart tariffs - the worst possible time for the dryer.
🌿 All figures are indicative at ~33-35c/kWh day rate - your exact tariff is on your bill.
🏆 The Running-Cost League Table (Per Use)
🌿 Electric shower (9.5kW): ~1.6 kWh per 10-minute shower ≈ 50-55c. A family of four showering daily is €700+ a year of electricity.
🌿 Immersion (3kW): heating a full tank takes roughly 2-3 kWh ≈ 70c-€1. Left on all day by accident: €5+. A timer is the fastest payback in Irish energy.
🌿 Tumble dryer (vented/condenser): 2-3 kWh per cycle ≈ 70c-€1. A heat-pump dryer does the same load for ~0.6-1 kWh ≈ 20-35c - it pays its premium back over a few years of regular use.
🌿 Oven: ~1-1.5 kWh per hour ≈ 35-50c. An air fryer doing the same small job uses a quarter of that.
🌿 Dishwasher: ~1-1.5 kWh per cycle ≈ 35-50c - eco mode genuinely is cheaper (longer, cooler wash).
🌿 Washing machine: ~0.5-1 kWh at 40°C ≈ 17-35c; most of the cost is heating the water, so 30°C washes cost less again.
🌿 Kettle: ~0.11 kWh per litre boiled ≈ 4c. Boiling only what you need is real but small money.
🌿 Fridge-freezer: ~1 kWh per day ≈ 35c/day, €120-€130/year - always on, but efficient; a 15-year-old unit can use double.
🌿 TV and console: 0.05-0.15 kWh per hour ≈ 2-5c/hour. The evening's entertainment costs less than one kettle boil.
🌿 Portable electric heater (2kW): ≈ 66-70c per hour - the dearest heat in the house (see our electric heater running costs guide). If one runs daily, the real fix is insulation or proper heating, not the plug-in rad.
💡 What This Means for Your Bill
Take a typical 4,200 kWh annual usage: roughly speaking, water heating, laundry and cooking can account for a third to a half of it in a busy household. That is why usage advice that obsesses over standby lights misses the point - the path to a smaller bill runs through hot water and hot air. The three moves that matter:
🌿 Time-shift the movable loads: on a night-rate tariff, the dishwasher, washing machine, dryer and immersion all cost roughly a third as much after 11pm. Same appliances, same usage, smaller bill.
🌿 Control the immersion: a timer or smart switch so it heats water when you need it (ideally at night rate) - never "whenever someone remembered to flip it". Our hot water costs guide works out what a full tank actually costs to heat.
🌿 Check the tariff itself: none of this beats being on the wrong supplier - the switching gap is worth €550+ a year before you touch a single habit. Your smart meter data shows exactly when you use power.
⚠️ Common Mistakes to Avoid
🌿 Hunting phantom loads while the immersion runs wild: unplugging the microwave saves ~€5 a year; timing the immersion saves €100+.
🌿 Running the dryer at 5-7pm on a smart tariff: the single most expensive habit combination in the house.
🌿 Replacing appliances for tiny gains: a new fridge to save €60 a year rarely stacks up - but a heat-pump dryer for a heavy-laundry family does.
🌿 Drying clothes on radiators: feels free, but it loads your heating and pumps moisture into the air - see our ventilation guide for why that gets expensive.
🌿 Trusting wattage labels alone: a 2000W appliance used 5 minutes costs less than a 100W one running all day - kWh (power × time) is the only number that bills you.
❓ Frequently Asked Questions
🔹 What uses the most electricity in a house?
Anything heating water or air: electric showers, the immersion, tumble dryers, ovens and portable heaters. Electronics - TVs, laptops, phones - are minor by comparison.
🔹 How much does a tumble dryer cost per cycle?
Roughly 70c-€1 for vented and condenser dryers, or 20-35c for a heat-pump dryer, at typical 2026 day rates. On night rate, a third of that.
🔹 How much does the immersion cost to run?
About €1 per hour at 3kW on day rates - a full tank heat is typically 70c-€1. Left on accidentally all day, €5+. Fit a timer.
🔹 How much does an electric shower cost?
Around 50-55c per 10-minute shower at 9.5kW. Shorter showers and a lower power setting move it meaningfully - it is many households' biggest single electricity user.
🔹 Is it cheaper to run appliances at night?
On a night-rate or smart tariff, yes - night units typically cost half to a third of day units. On a standard 24-hour tariff, timing changes nothing until you switch.
🔹 How do I find out what an appliance actually uses?
A plug-in energy monitor costs €15-€25 and reads any socket appliance directly, and your smart meter app shows the whole house half-hour by half-hour.
📚 Related Guides
🌿 Best Electricity Provider
🌿 Electricity Prices & Average Bill
🌿 Night Rate Electricity
🌿 Pay-As-You-Go Electricity
🌿 MPRN & GPRN Numbers
🌿 ESB Smart Meter Error
🌿 Hot Water Costs
🌿 Electric Heater Running Costs
🌿 Dehumidifiers
👉 All guides and calculators
Climate Jargon Buster is an independent resource providing plain-English information on climate, energy and sustainability topics for an Irish audience. All running costs are indicative, based on typical 2026 standard rates of ~33-35c/kWh and typical appliance consumption - your appliance, settings and tariff will vary. Check your own bill for exact unit rates.