In the “2024 Energy Literacy Study,” ERSE outlines a portrait of Portuguese consumers’ perceptions, knowledge, and behaviors regarding energy. The study reveals that only 18% of respondents demonstrate a high level of energy literacy, while most have only basic knowledge and tend to confuse key concepts such as contracted power, consumption, and billing.
In this context, understanding the electricity bill becomes essential for more efficient energy consumption management and identifying opportunities for savings. Although the bill format may vary depending on the supplier, there are common elements that all consumers should know and interpret correctly.
1. Contract Information
The electricity bill includes key information about the supply contract, such as the account holder’s name, supply address, Delivery Point Code (CPE) — a unique identifier of the electrical installation — contracted power, tariff, and selected time-of-use cycle.
Contracted Power
Contracted power is the maximum amount of energy that can be used simultaneously in a household. It is measured in kilovolt-amperes (kVA) and determines how many appliances can operate at the same time without triggering the main circuit breaker. The bill should state the contracted power and its associated cost.
- Example: If you turn on the oven, washing machine, and air conditioner simultaneously, and the contracted power is insufficient, the circuit breaker may shut off automatically.
- Ideal choice: A small apartment may require 3.45 kVA, whereas a larger house may need 6.9 kVA or more.
- Adjustment: If power is frequently cut off due to the use of multiple devices at once, you may need to increase the contracted power. Conversely, if you rarely reach the limit, reducing it could save money on your bill.
Tariff
The tariff determines the price of electricity and may vary depending on the supplier, type of contract, and usage profile. The main types of tariffs include:
- Single-rate tariff: The kWh price is the same throughout the day.
- Two-rate (bi-hourly) tariff: The price varies depending on the time of day, with cheaper periods (typically at night and weekends) and peak periods (during the day, when electricity is more expensive).
- Three-rate tariff: Adds a third transition period between peak and off-peak hours.
Selected Time-of-Use Cycle
The time-of-use cycle applies to two- and three-rate tariffs and defines when electricity is cheaper or more expensive during the day.
There are two main types:
- Daily cycle: Cheaper rates at night every day of the week.
- Weekly cycle: Cheaper rates at night and throughout the weekend.
2. Supplier Information
The bill includes supplier contact details, such as customer support, fault reporting, and meter reading submission.
3. Energy Consumption
The bill provides the total amount due, payment deadline, and a breakdown of costs, including energy consumption based on actual or estimated readings.
- Actual readings are taken directly from the meter.
- Estimated readings are calculated using the customer’s consumption history.
The bill also indicates the billing period and the consumption recorded in kilowatt-hours (kWh).
4. Fees and Taxes
- Access Tariff to the Grid: A regulated charge set by ERSE (the Portuguese Energy Services Regulatory Authority). It compensates transmission and distribution system operators and depends on contracted power.
- Audiovisual Contribution: Funds the public broadcasting service. Charged by the Portuguese Tax and Customs Authority, the standard monthly fee is €2.85 + VAT (6%), reduced to €1 + VAT (6%) for those on the social tariff. Consumers using less than 400 kWh per year or engaged in agricultural activities are exempt.
- Special Electricity Consumption Tax (IEC): Part of the Excise Duties group, similar to fuel taxes. This environmental tax encourages energy efficiency. The rate is €0.001 per kWh consumed.
- DGEG Supervision Fee: A fixed monthly fee (around €0.07) that supports the Directorate-General for Energy and Geology’s activities in regulating and monitoring the energy sector.
- VAT: Applied to the total bill. A 6% rate is applied to part of the bill (e.g., fixed charges and consumption up to 100 kWh/month for contracted powers up to 6.9 kVA), and 13% or 23% applies to other components, as per current legislation.
5. Additional Information and Transparency
The bill should also include:
- Payment conditions, deadlines, and methods
- Consequences of late payment
- Social tariff discount (if applicable)
- Comparison between the current rate and what would be paid under the regulated tariff
- CO₂ emissions associated with consumption and the share of energy sources used (wind, hydro, natural gas, coal, etc.) — mandatory under European Directive 2009/72/EC, helping consumers assess the sustainability of their energy use
The social tariff is an automatic discount for economically vulnerable households, reducing electricity bills by up to approximately 33.8%. It is granted based on eligibility criteria established by Social Security and the Tax Authority.
