Utilitarian Spot — energy prices for automation
A free public-good electricity-price API and analysis site with static JSON endpoints, day-ahead graphs, historical data and push notifications.
The problem
Utilitarian Spot was built as a free public-good resource for simpler access to Swedish electricity prices without relying on Nord Pool scraping.
What Henrik owned
Henrik built and operates the service, including the data collection jobs, static API files, frontend views, historical data tooling and notification infrastructure.
Work delivered
- Published each API endpoint as a static file on GitHub Pages
- Automated data collection with GitHub Actions that commits new and changed files before publishing the site
- Collected ENTSO-E data and scraped historical data for broader coverage
- Added scheduled jobs for ongoing price-data updates
- Updated the API for quarterly prices after users relied on it for wind-power plant control
- Added uPlot day-ahead graphs and a full historical data analysis tool
- Added push notifications using a service worker and Cloudflare Workers
- Put Cloudflare in front of the site
Technical approach
The service is intentionally simple, fast and lightweight: scheduled GitHub Actions collect data, write API responses as static files, commit the changed files and publish the GitHub Pages site. Cloudflare sits in front, with workers and a service worker handling push notification functionality.
Where it stands
Live free public electricity-price resource used by automation and energy applications, serving over 12 million requests per month with around 14 ms p50 and 44 ms p95 response times.