Wholesale prices and your electricity bill

The price card displays an Elexon Market Index Price using this site’s APXMIDP provider filter. It is a wholesale indicator for a particular period, not a quote for electricity supplied to your home.

Convert the unit, not the meaning

There are 1,000 kWh in a MWh and 100 pence in a pound. Divide £/MWh by ten to express the same value in p/kWh: £150/MWh equals 15 p/kWh. That calculation changes the unit only; it does not turn a market observation into a household tariff.

Why a retail bill differs

A retail tariff can include costs beyond wholesale energy, and suppliers can buy energy for different times and on different terms. Standing charges and contracts also matter. Do not use one index reading to calculate your bill or assume a retail rate should immediately match it. Use your own contract’s rates for billing calculations.

Retrieval time and period time

Suppose a successful download occurs at 14:10 but the latest available period begins at 13:30. The first timestamp describes retrieval; the second identifies the price period. A working connection does not establish that newer upstream records have been published. Both timestamps matter when judging freshness.

What the archive preserves

The updated long-term archive stores original price-period timestamps separately from hourly electricity observations. Zero and negative prices remain numbers rather than failed downloads. Missing periods remain gaps. Legacy hourly price fields cannot recreate half-hour periods that were never retained.

Compare prices carefully

Check the selected period, minimum, maximum and coverage. An arithmetic mean of displayed prices is not a volume-weighted purchase price. When comparing prices with generation, align the periods and distinguish association from causation. The charts alone do not show why a particular price formed.

Elexon Market Index Prices · Explore price history · All guides