Electricity tariff workbench

01 · Annual consumption by period (kWh)

Billing model

Input source Illustrative example My own bill / offers

kWh · 1

kWh · 2

kWh · 3

02 · A / B

Prices are examples, not live offers. Choose your billing model, then replace the figures from both contracts. Power fees are €/kW/day in Spain and €/kW/year in Italy. Put every other fixed charge in the annual fixed field.

A · Current / reference offerEnergy pricing

Energy price (€/kWh) · 1

Energy price (€/kWh) · 2

Energy price (€/kWh) · 3

Fixed charges (€/year)

Contracted power (kW) · 1Power charge · 1

Contracted power (kW) · 2Power charge · 2

One-off bonus (€)

B · Alternative offerEnergy pricing

Energy price (€/kWh) · 1

Energy price (€/kWh) · 2

Energy price (€/kWh) · 3

Fixed charges (€/year)

Contracted power (kW) · 1Power charge · 1

Contracted power (kW) · 2Power charge · 2

One-off bonus (€)

One-off switching costs for B (€)

Move consumption to another period / What if B’s energy price changes?

kWh/year moved from the first to the last period

Change in B’s energy rates (±%)

I have included all applicable taxes, levies and network charges in the prices, without double counting.

03 · Your comparison

Saving with B · First year

Saving with B · Following year

Saving over two years

Positive savings mean B costs less than A. A negative value means B costs more.

Annual cost breakdown
€ / per year	A	B

Saved comparisons

Import JSONChoose fileNo file selected

Import consumption CSVChoose fileNo file selected

Use the template headers. One row per measured period; the tool sums kWh and never extrapolates to a year. Enter or import a full year. Semicolon files accept decimal commas.

How the calculation works

Annual recurring cost = Σ(consumption × all-inclusive rate) + fixed charges + contracted power charges. First-year cost subtracts the one-off bonus; B also adds switching costs. Two-year savings = first-year savings + recurring savings. France’s break-even uses recurring costs, excluding bonuses. The shifting scenario stays separate.

Limits of this comparison

A 365-day model with constant consumption and prices. It does not forecast index-linked prices, model real hourly schedules, solar export, social tariffs or contract eligibility. Verify bonus conditions, term and exit fees with the supplier. A negative bill can result from an unusually large entered bonus. This is arithmetic, not a switch recommendation.

Privacy

Figures stay in your browser unless you export or deliberately share them. Saved comparisons use local storage; up to five entries. A share URL contains the numbers in its fragment. Anonymous interaction counts include only language, market and example/own-input choice, never bill values. No account is needed.

Sources and official comparison services

2026-09-25 · EcoBack