ahorr.ai · Blog
Electricity Bill Audit: A Forensic Breakdown to Stop Overpaying
Respuesta rápida
An electricity bill audit involves a detailed review of your contracted power, energy consumption, and additional services to identify billing errors or optimization opportunities. In the Spanish market, understanding the breakdown of regulated costs and free market rates is essential to avoid paying for unnecessary maintenance services or oversized power levels.
En 30 segundos
- ✓Locate the 'Contracted Power' section and check your peak usage history
- ✓Identify 'Other Services' or 'Maintenance' line items you didn't explicitly request
- ✓Calculate your effective price per kWh (Total cost divided by Total kWh consumed)
Ready for a forensic audit?
Upload your bill and let our AI find the hidden costs in 30 seconds. No registration required.
Why you can trust it
- Free and no signup
- AI trained on the Spanish market (~30s)
- Privacy-first: ephemeral processing (we don't store your bills)
Transparencia y fuentes
Authorship, methodology and official sources.
Actualizado: 10 de enero de 2026
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Transparencia y fuentes
Authorship, methodology and official sources.
Actualizado: 10 de enero de 2026
Autoría
Equipo ahorr.ai
Auditoría energética (España)
Metodología orientada a decisión: separar coste fijo/variable, detectar extras y comparar opciones con números claros.
Metodología
- →Separamos coste fijo (potencia/término fijo), energía y cargos/impuestos.
- →Buscamos sobrecostes típicos: potencia sobredimensionada, servicios extra, lecturas estimadas.
- →Damos pasos accionables (qué tocar primero) con ejemplos orientativos, no promesas.
- →Enlazamos fuentes oficiales y marcamos lo que puede variar por comercializadora.
Información orientativa (España). Comprueba condiciones con tu comercializadora: precios, peajes, cargos e impuestos pueden variar.
The Typical Culprits (And How They Look in the Breakdown)
An electricity bill audit is like a forensic investigation. You aren't just looking at the total; you are looking for the fingerprints of overspending across different categories.
Fixed vs Variable Costs
The fixed part (Power) is what you pay for the right to turn on appliances. Many Spanish households are 'oversized', paying for 5kW when they only ever use 3kW. The variable part (Energy) is where the tariff price per kWh dictates your fate.
Extras Invisibles
Look for terms like 'Protección Eléctrica', 'Servicio Urgencias', or 'Mantenimiento'. These are often added during sign-up and provide little value for the average user, acting as 'vampires' that drain your monthly budget.
What to Review in Your Bill (The Paper Trail)
To perform a manual 'auditoría factura luz', you need to focus on specific technical sections that companies often hide in small print.
Where to Look
Check the 'Datos del Contrato' section. This is where the CUPS code and the contracted power (Potencia Contratada) are listed. Also, look for the 'Detalle de la Factura' to see the line-by-line cost breakdown.
Which Numbers to Record
Note down your 'Potencia Máxima Demandada' if it appears (usually in a small graph or table). If your maximum demand is significantly lower than your contracted power, you are losing money every month.
Real Case: The Culprit Wasn't the kWh
Sometimes, the biggest saving doesn't come from turning off the lights, but from fixing the contract structure.
The Clue
In our forensic audit of a 90m² flat, the family was paying 0.23 €/kWh. While high, the real shock was the 4.6 kW power rating for a home that never used more than 2.8 kW simultaneously.
The Correction
By reducing the power to 3.3 kW and removing a 6.99 € maintenance service, the family saved over 150 € per year without changing their lifestyle at all.
Quick Solution: Autopsy with ahorr.ai
Manual audits are tedious. Our AI-driven tool performs a full autopsy of your bill in under 30 seconds.
What it Detects
Our engine identifies if your power is sobredimensionada, if you are paying for 'vampire' services, and how your current price compares to the top 3 cheapest tariffs in the Spanish market.
What to Do with the Report
Once you have the forensic report, you have the proof needed to call your company and demand a change, or switch to a provider that actually fits your consumption profile.
Your Electricity Bill Audit Checklist
- ✓Locate the 'Contracted Power' section and check your peak usage history
- ✓Identify 'Other Services' or 'Maintenance' line items you didn't explicitly request
- ✓Calculate your effective price per kWh (Total cost divided by Total kWh consumed)
- ✓Compare your current tariff against the PVPC (regulated market) reference
- ✓Verify if you have 'Time Discrimination' (DH) and if your habits align with cheaper hours
Common Symptoms Found in a Bill Audit
| Symptom | The Culprit | The Forensic Fix |
|---|---|---|
| High fixed cost even with low usage | Oversized Contracted Power | Lower the kW to match your real peaks |
| Recurring small amounts (5-10€) | Vampire Maintenance Services | Cancel unnecessary insurance/services |
| Variable cost higher than 0.20 €/kWh | Outdated Market Tariff | Switch to a competitive fixed or indexed rate |
| Price spikes during the day | Lack of Time Discrimination | Adjust habits or switch to a flat-rate tariff |
Estimates based on standard Spanish market conditions.
The Case of the 4.6 kW Ghost
A family living in a 90m² apartment in Madrid couldn't understand why their bills remained high even when they were careful with consumption. Upon performing an electricity bill audit, we discovered they had 4.6 kW of contracted power, while their actual peak usage never exceeded 2.8 kW. Additionally, a 'premium' maintenance service was quietly draining their bank account every month.
Hallazgos
- ✓Contracted power was 65% higher than necessary
- ✓Hidden maintenance service costing 6.99 €/month
- ✓Effective price of 0.23 €/kWh was significantly above market average
Ready for a forensic audit?
Upload your bill and let our AI find the hidden costs in 30 seconds. No registration required.
Related guides
Preguntas frecuentes
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Disclaimers
- Informational tool; not financial advice.
- We don’t guarantee savings: these are estimates.