Spanish homes have a reputation for being cold in winter and hot in summer. Thin walls, single-glazed windows, no central heating, ceramic-tile floors — designed for the eight months of the year when it doesn't matter. The other four months, your bill notices.
Here are practical fixes for both seasons. Numbers are euros, not slogans.
Winter: keeping warm without frying the bill
1. Drop the thermostat 1°C → save 7%
Going from 21°C to 20°C in the living room cuts heating consumption by about 7%. From 22°C to 19°C: 20%. Wear a hoodie. No energy expert objects.
2. Heating is a thermostat, not a switch
Turning heating on and off as you arrive and leave doesn't save money. What saves money is maintaining a moderate constant temperature. A programmable thermostat at 19°C from 06:00–23:00 and 17°C overnight is optimal for most.
If you go away for a weekend, don't turn it off completely. Leave it at 15°C. Reheating a cold home from 10°C uses more than maintaining it.
3. Close shutters at dusk
Spanish persianas (roller blinds) are insulation gold. Lower them at sunset (around 18:00 in winter) to keep 2–3°C extra in the room overnight. Cost: zero. Time: two seconds.
4. Use the free sun
Midday sun in a south-facing room = free heat. Open the blinds and curtains. A well-oriented room with two hours of direct winter sun gains 3–5°C with zero electricity.
5. Wash at 30°C, not 40°C
Modern washing machines clean perfectly at 30°C unless you're tackling sportswear or heavy stains. Going from 40°C to 30°C cuts the cycle's energy use by 40% (most of the energy heats the water).
Combine with off-peak hours and the savings double.
6. Schedule the electric water heater
If your hot water comes from an electric water heater (termo eléctrico), it's probably the single biggest consumer in your home (3 kWh per full cycle).
Schedule it to heat only between 00:00 and 06:00 (off-peak hours). A plug-in timer costs €12 at any hardware store. Typical savings: €80–€150/year.
Summer: surviving the heat without sticker shock
7. Set A/C to 26°C, not 22°C
The recommended summer indoor temperature in Spain is 26°C, not 22°C. Each degree below 26°C adds about 8% to A/C consumption. A unit running at 22°C uses 30%+ more than at 26°C — for marginal comfort difference if you have a fan running.
A ceiling fan adds the equivalent of 3°C of cooling perception while using 1/30th the electricity.
8. Use night air
In most of Spain, nights drop below 22°C even in July. Open windows at 23:00 and close them (with shutters down) at 09:00, before the heat returns. Free natural cooling for 4–6 months a year.
9. Block the morning/afternoon sun
External shading beats internal shading. Toldos (awnings) are the Spanish standard for a reason — they block sun before it hits glass. If you don't have toldos, lower your persianas during the hours when sun hits that window directly.
A south-facing window with full sun for 6 hours can gain 4–6°C indoors. Block that and you can run the A/C at 26°C instead of 24°C.
10. Defrost the freezer once a year
A 1cm layer of ice on freezer walls increases consumption by 20%. Defrosting takes 4 hours and saves about €15/year. Plus you find what's been at the back since 2024.
Year-round wins
11. Kill phantom load
Standby appliances draw 5–15W each, all 8,760 hours of the year. Add up:
- TV in standby: 8W × 24h × 365 = 70 kWh/year (~€12)
- Set-top box: 12W = €18/year
- Phone chargers plugged in without phones: 1–2W each
- Microwave clock: 2W × 24h = €2/year
A switched power strip behind the TV that you flick off at night = €30–50/year of effortless savings.
12. Check your contracted power
Most Spanish homes have more contracted power than they need — typically 5.5 kW from before LED lighting and efficient appliances. 4.4 kW is enough for almost any household.
Dropping from 5.5 kW to 4.4 kW = €30/year of permanent savings. You change it online via your distributor's website, free, in 5 minutes.
How to know if you're over-contracted? If your breaker has never tripped, you probably are.
The bonus trick almost nobody uses
Look at the 24-hour PVPC heatmap for tomorrow (it's published around 20:15). If tomorrow's 14:00 price is 0.06 €/kWh and the 20:00 price is 0.18 €/kWh, bring forward what you can to 14:00: laundry, dishwasher, ironing, drying.
The homepage shows it live with the cheapest hour highlighted green. Zero effort, daily savings.