How Tariff Savings Are Calculated

This page shows the exact slot-by-slot maths behind your savings, using the same assumptions and scenario engine as the detailed analysis view.

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1) Inputs Used

Each day is split into 48 half-hour slots. For every slot we evaluate import, export, and tariff rates before summing to a net daily cost.

Slot Energy Inputs

    Tariff Rate Inputs

      Battery & Solar Assumptions

        2) Core Formula (Per Slot and Per Day)

        For each slot i: cost contribution = import cost minus export credit. Daily total is the sum over all 48 slots.

        slotCost_i = (gridImport_i x importRate_i / 100) - (gridExport_i x exportRate_i / 100)
        dailyCost = sum(slotCost_i for i = 1..48)
        dailySaving = currentDailyCost - scenarioDailyCost
        annualizedSaving = dailySaving x 365

        Current Scenario

        
                

        Better Tariff Scenario

        
                

        Otto Ideal Scenario

        
                

        3) Scenario Differences

        All scenarios use the same day and slot structure, but differ in rates, dispatch rules, and flexibility assumptions.

        Current

          Better Tariff

            Otto Ideal

              4) Worked Example (6 Half-Hour Slots)

              Sample rows below are taken directly from today’s 48-slot run. Each row shows energy, rates, and net contribution for all three scenarios.

              Slot Cur Imp kWh Cur Exp kWh Cur Rates p Cur Slot £ Better Imp Better Exp Better Rates p Better Slot £ Ideal Imp Ideal Exp Ideal Rates p Ideal Slot £
              Sample subtotal (6 slots) £0.00 £0.00 £0.00

              5) Daily & Annualized Savings Summary

              Daily values come from all 48 slots. Annualized values are a simple daily × 365 estimate.

              Current Daily Net

              £0.00

              Better Tariff Daily

              £0.00

              Otto Ideal Daily

              £0.00

              Better Tariff Saving

              £0.00/day

              Otto Ideal Saving

              £0.00/day