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    Transformer Loss & Energy Cost

    Annual transformer loss energy and energy cost from the no-load loss P0 and the load loss Pk (estimate).

    EstimatePreliminary result, not a design verification.
    Before you calculate

    Transformer losses and their yearly energy

    From the no-load loss P0 and the load loss Pk of your transformer's test report; the cost uses your own energy rate. An energy estimate, not a utility bill.

    Learn more — complete guide →
    Step 1

    Transformer losses and operation

    The default P0 and Pk are ILLUSTRATIVE placeholders, not data of your transformer: use its test report or nameplate.

    Constant or RMS-equivalent loading; the load loss goes with its square.
    Advanced: load intervals, currency, power factor, overload mode (optional)
    Step 2

    Results

    Check before relying on this result
    • P0 and Pk are ILLUSTRATIVE placeholders, not data of your transformer: enter the values from its test report or nameplate.
    Annual loss energy34164 kWhReference estimate · core 12264 kWh + load 21900 kWh
    Annual cost at your rate5124.60 €An energy estimate, not a guaranteed bill.
    Losses while energized3.900 kWP0 1.400 kW + load 2.500 kW

    Energized hours counted: 8760 h.

    Not modelled: winding temperature correction, harmonics, cooling fans and pumps, tap position, ageing and hot spot. A comparison of two transformers needs the same hours, load profile, energy rate and loss reference temperature. No IEC compliance statement.

    1. Losses at the loading

    No-load loss whenever energized; load loss with the square of the loading x = I/I_rated.

    Ptotal≈P0+Pk x2P_{total}\approx P_0+P_k\,x^2
    Ptotal≈1.4+10×0.52=3.9 kWP_{total}\approx 1.4+10\times 0.5^2=3.9\ \text{kW}

    2. Annual energy

    Constant loading for the energized hours.

    E≈H (P0+Pk x2)E\approx H\,(P_0+P_k\,x^2)
    E≈12264+21900=34164 kWhE\approx 12264+21900=34164\ \text{kWh}

    3. Annual cost

    Your own energy rate; no tariff is universal.

    C=E×cC=E\times c
    C=34164×0.15=5124.6C=34164\times 0.15=5124.6

    Calculations use full precision internally; the displayed numbers are rounded for readability.