From Excel to a Native NZ Electricity Market Application
A deliberately local, self-contained macOS application for EDB and electricity market analysis.Built for people who need a single, reliable source of truth — without the complexity of cloud infrastructure.
How it evolved
My first electricity market dashboard was built when I was the sole analyst at a small gentailer. We needed a single source of truth for Board reporting, covering generation, hedging, retail and sales. It lived in Excel, with NZX reports manually entered for each revision. It worked — but it was labour-intensive and introduced real risks around consistency and data entry.
The next version was developed at a nationwide retailer. The challenge was larger: reconciling approximately $65 million per year of network tariffs against customer invoices and NZX submission volumes. This introduced proper database integration and moved the workflow beyond spreadsheets.
Later came R scripts that audited and reconciled network billing data and handled different formats of half-hourly metering data. The process became repeatable and consistent, and manual data entry largely disappeared.
The latest evolution is a native macOS application that brings all of these capabilities together.
Designed to stay on one machine
The data is deliberately kept on a single machine. This is a feature, not a limitation.
There is no cloud infrastructure to manage, no dependency on external services, and no need to move sensitive operational data through another system. The application is fast, self-contained, and runs comfortably on a Mac mini.
The result is a progression from a manually maintained Excel dashboard, through database integration and automated R workflows, to a dedicated application with a simple and deliberately local architecture.
Each step has had the same objective: reduce manual work, improve consistency, and create a reliable source of truth for electricity market analysis.
- Single source of truth for generation, hedging, retail and network positions
- Reconciliation of network tariffs against invoices and NZX volumes
- Consistent handling of half-hourly metering data
- Local, self-contained architecture — no cloud dependency
Happy to walk through the architecture or the reconciliation approach if it looks relevant to your EDB or electricity retail operation.
Malcolm Souness
021 565 557
