TopN Analytics
Success Story

Capacity Planning: Actual Load vs. Contracted Demand

A charge point operator (CPO) partner operating a multi-hub charging network with contracted electricity demand agreements.

Challenge

Where things stood

CPOs typically pay for electrical capacity under a contracted demand agreement, but whether that capacity matches real-world usage is often invisible without dedicated monitoring.

Both failure modes are costly: paying for unused contracted capacity, or exceeding contracted demand and risking penalties or supply interruptions.

Architecture

What we built

High-resolution (15-minute interval) power-meter readings (Timescale) across every connector, spanning dozens of hub locations, join connector/station metadata (PostgreSQL) and contracted demand reference data (BigQuery).

A Python aggregation pipeline explicitly zero-fills usage gaps so peak-usage analysis isn't skewed by missing data, then joins actual peak power draw per hub per interval against each hub's contracted electricity demand.

Output refreshes daily into a BigQuery dashboard table via Apache Airflow.

Solution

How it works

TopN Analytics built a pipeline that pulls high-resolution power-meter readings and compares actual peak power draw per hub against contracted capacity, giving CPOs a defensible, granular basis for renegotiating contracted demand agreements.

Key Takeaways

What we delivered and learned

The zero-filling design decision matters: an analysis built only from intervals with recorded usage would understate how often a hub is actually idle, distorting conclusions about whether contracted capacity is over- or under-sized.

Tech Stack

What it's built on

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