How the numbers are built, what is checked before they are used, and what this work does not claim to be.
Datum Markets is one person: an accountant who rebuilds power market numbers from published primary sources, working from the United Kingdom on southern African markets. There is no data feed behind this and no panel of contributors.
Public primary sources only: Eskom's published tariff rates workbooks, Eskom's Schedules of Standard Prices, and NERSA's published decisions. Every figure carries a reference to where it came from, down to the cell in the workbook, so you can open the source and check it rather than take it on trust. Where a number cannot be traced to a published document, it is not used.
Rates are cross-checked between two independently published Eskom documents before they are used. The generation capacity charge was checked this way across 2025/26 and 2026/27: sixteen values, four voltage bands by two tariff years, VAT exclusive and VAT inclusive, all matching between the rates workbook and the Schedule of Standard Prices.
The calculation engine has an automated test suite that runs on every change. Every check is backed by a fixture: a deliberately broken input proving that check actually fires. A check cannot be added without a test showing it can fail. The suite ran green at 73 assertions across 60 fixtures on 26 September 2026.
Every deliverable is dated and states which tariff year it used and which source documents it was built from, so the same result can be reproduced later rather than taken on its word.
It is analysis. Nothing here is financial, legal or investment advice.
A reconciliation is not a formal audit opinion and does not carry one.
We cannot confirm your meter readings. We can tell you whether the charges follow from those readings and the published rules.
Working files are held in a version-controlled repository, so every figure in a deliverable can be traced back to the calculation and the source document that produced it. You can ask for the full working detail behind any figure at any time.
Send the figures from a recent Eskom invoice. We return the reconciliation within five working days.