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Commercial electricity is not one number. The meter (and the bill) can report active, reactive, and apparent energy. VoltView stores all three when the supplier or the invoice provides them.

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The three quantities

On a clean sine wave they form a right triangle:
Power factor is active ÷ apparent (kW / kVA, or kWh / kVAh over the same interval). A site that draws 80 kW and 100 kVA is at 0.8 PF.
Reactive energy has a cycle-average of zero — it is not “used up” the way kWh is. The network still has to carry the extra current, so suppliers charge for it when power factor is poor, and they size capacity in kVA rather than kW. See Demand and capacity.
Export uses the same units. A solar site can have activeExportKwh on the export MPAN. Reactive import/export are electricity-only; they do not apply to gas.

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What you see on a bill

A typical C&I invoice line-up: Day and night kWh are still active energy. They are the same kWh split across registers, not a different physical quantity. If the invoice kWh and the half-hourly sum disagree, check the billing multiplier and the read types (actual vs estimated) before assuming the meter is wrong.

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How modern meters get kWh and kvarh

The meter samples voltage and current, multiplies them, and integrates:
  • Instantaneous v × i, averaged over a cycle, is active power.
  • Apparent power is Vrms × Irms.
  • Reactive power is the remaining leg of the triangle on a sine wave. Meters use several practical methods (a 90° shift of one waveform, a filter, or the triangle itself). They diverge once the waveform is distorted.
VoltView does not recompute kvarh from kWh. We take the meter or the invoice value. If only kWh is present, we do not invent a power factor.

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Billing multiplier

On a whole-current meter the face reading is kWh. On a CT-metered supply the instrument sees a stepped-down current (usually 5 A). HV sites also step voltage down through a VT (PT). The true primary quantities are much larger.
Leave the VT term at 1 on a 400 V CT-metered board — the meter still sees line voltage. Billed kWh for the period is:
The multiplier is printed on the meter face when it is not 1, and it is almost always printed again on the invoice. Four-dial meters may also be ×10, or may record only a fraction of true kWh.
A register read in VoltView is the index, not the billed energy. If you compare currentMeterReading − previousMeterReading to consumptionkWh and they differ by a round factor (10, 20, 40, 80, 200, 400…), you are looking at an unapplied CT/VT multiplier, not a parse error.

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What we do not do

  • Infer kvarh or kVAh from kWh and a guessed power factor.
  • Apply a silent multiplier to a smart-meter interval series. HH settlement data is already in true kWh.
  • Treat inverter kWh as a substitute for the settlement meter. Generation is mapped next to the MPAN; it does not replace it. See Solar.