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Compare annual electricity tariffs

Compare first-year and recurring electricity costs using your actual tariff inputs.

Free working edition. Named workspaces and exports are local to your device. Team sync, automatic source monitoring and paid memberships are not available.

All prefilled business examples are fictional. Replace them with your own checked inputs.

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Your result

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How this tool works

First year = annual kWh × unit price + 12 × monthly fee − one-time credit. Following year excludes the one-time credit.

Method version: 2026-09-19.2

Input format

No automatic currency conversion. CSV headers remain English; use decimal points and ISO dates (YYYY-MM-DD).

Annual electricity use (kWh)
kwh
Tariffs, one currency
tariff,currency,unit_price,monthly_fee,one_time_credit

Reproducible example

All prefilled business examples are fictional. Replace them with your own checked inputs.

Scroll horizontally to see all columns.
TariffCurrencyEnergyStanding feesOne-time creditFirst yearFollowing year
Sample AEUR960.00144.00100.001,004.001,104.00
Sample BEUR864.00192.000.001,056.001,056.00

Limits and assumptions

Unit price is currency per kWh, not cents. Monthly standing fees are multiplied by 12. One-time credits apply only in year one.

Taxes must already be included in your inputs. This does not model tiered tariffs, eligibility or cancellation fees. No supplier switching occurs.

Sources and specifications

RFC 4180 — CSV format

Read the text version · Download example inputs

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BillLens — Compare annual electricity tariffs