Endesa Power Calculator (Potencia Contratada)
Estimate the contracted power level for your home and the monthly fixed power term. Select appliances that can run at the same time during your peak usage hour.
1) Peak Appliance Load
| Use at Peak | Appliance | Power (W) |
|---|---|---|
| Fridge | ||
| Oven | ||
| Induction / Hob | ||
| Washing Machine (heating phase) | ||
| Dishwasher | ||
| Microwave | ||
| Air Conditioner | ||
| Electric Heater | ||
| EV Charger (single phase typical) |
2) Tariff and Tax Inputs
What is an Endesa power calculator?
An Endesa power calculator helps you estimate your ideal potencia contratada (contracted power in kW) and the fixed part of your electricity bill. In Spain, this number matters a lot: if your contracted power is too low, your breaker can trip when several appliances run together. If it is too high, you can overpay every month for power you do not need.
This page is designed to make that decision easier. You can add your likely simultaneous appliance load, apply a safety margin, and quickly see a recommended power tier and monthly fixed-power cost estimate.
Why contracted power is so important
Many households focus only on energy consumption (kWh), but power (kW) is a separate part of the bill. Think of it this way:
- kW (power): how much electricity you can draw at one moment.
- kWh (energy): how much electricity you consume over time.
Even if your monthly kWh usage is moderate, having an oversized contracted power increases your fixed charges. Right-sizing power is one of the cleanest ways to reduce long-term electricity costs without changing comfort.
How this Endesa power calculator works
1) Build your realistic peak usage
The calculator adds appliance wattage only for devices that may run at the same time during your busiest period (for example, dinner time with cooking + HVAC + other loads). This gives a practical peak load in watts.
2) Add a safety margin
No home load profile is perfectly constant. Startup spikes, extra devices, and seasonal changes can push demand higher. A 15%–25% margin is common for households that want fewer nuisance trips.
3) Round up to a standard contracted tier
Contracted power is usually selected in standard steps. The tool rounds to the next available tier so your plan is viable in real life.
4) Estimate fixed monthly power cost
The fixed cost estimate is calculated from:
- Contracted power (kW)
- Power price (€/kW/day)
- Billing days
- Electricity tax
- VAT / IVA
Typical appliance power references
If you are unsure what numbers to enter, these are common ranges for many homes:
- Fridge: 100–250 W (continuous cycling)
- Microwave: 900–1500 W
- Oven: 1800–2800 W
- Induction zone/hob usage: 1200–3000 W depending on burners and level
- Washing machine heating cycle: 1500–2200 W
- Dishwasher heating cycle: 1500–2200 W
- Split air conditioning: 700–1800 W
- Portable electric heater: 1000–2500 W
- Single-phase EV charging: commonly around 2300 W to 3700 W
Always prioritize your appliance nameplate data for best accuracy.
Example scenario
Suppose your peak moment is fridge + oven + induction + AC + some miscellaneous loads. The sum might land near 5,300 W. With a 20% margin, required power is around 6.36 kW. The next standard tier could be 6.90 kW (single phase), which is likely safer than 5.75 kW for this household profile.
From there, the calculator estimates your monthly fixed power term using your selected tariff and tax assumptions, helping you compare whether stepping down or up by one tier is worth it.
How to reduce your bill without sacrificing comfort
- Stagger high-load appliances: avoid running oven, washer heating cycle, and EV charging at the same time.
- Use smart scheduling: run dishwasher/washer at off-peak hours if your tariff rewards that behavior.
- Check HVAC efficiency: old resistance heating can dramatically raise peak load.
- Monitor real peaks: a smart meter or energy monitor gives better data than guesswork.
- Reassess yearly: lifestyle changes (remote work, EV, new appliances) can shift optimal power.
Frequently asked questions
Can I use this tool for apartments and houses?
Yes. It works for both, as long as your inputs reflect your true simultaneous load profile.
Does this include the energy consumption part of the bill?
No. This calculator focuses on contracted power and the associated fixed term. Energy usage (kWh) charges depend on your consumption and tariff periods.
What if my result exceeds standard tiers?
If your estimated requirement is above typical stepped values, consider professional review, phase configuration checks, and distribution constraints. Large loads like EV charging plus electric heating can require a different setup.
Final takeaway
A good Endesa power decision is a balance: low enough to avoid paying for unused capacity, high enough to prevent breaker trips. Use the calculator above as your starting point, then confirm final contract changes with your supplier and distribution rules in your area.