TariffAnalyser — Indigo Plugin

Compares your real recorded energy flows against UK electricity tariffs to show what you would have paid on each tariff.

The SigenEnergyManager plugin records your energy flows every 30 minutes. TariffAnalyser reads that record, works out what each tariff would have cost you, and writes an HTML report that opens in your browser.

Features

• Half-hourly comparison using your actual grid import, export, solar generation, and battery usage
• Supports Octopus Tracker (actual per-slot prices), Go, Go Faster, Agile, Cosy, Flux, Economy 7, Ofgem SVT price cap, E.ON, EDF, and Scottish Power
• Fair like-for-like ranking — every tariff is priced over the same set of half-hourly slots (those where all selected tariffs have a price), with the standing charge pro-rated to that set. A tariff with too little price data is flagged as insufficient rather than ranked misleadingly cheap
• Export revenue comparison: Octopus Outgoing 12p, Agile Outgoing, SEG minimum, SEG typical
• Octopus Agile prices fetched automatically from the public API (no credentials needed)
• Reports come out as HTML and open in your browser
• Schedulable actions: generate a report, update Agile price data, refresh the daily summary
• Menu items for on-demand use, including a Test Octopus API Connection check

Requirements

• Indigo 2022.1 or later (Python 3.10+)
• SigenEnergyManager v4.6+ (provides the half-hourly energy database)
• A web browser to read the reports — any Mac already has one

Installation

1. Go to the Releases page and download TariffAnalyser.indigoPlugin.zip
2. Unzip the downloaded file — you will get TariffAnalyser.indigoPlugin
3. Double-click TariffAnalyser.indigoPlugin — Indigo will install it automatically

Credentials — IndigoSecrets.py vs IndigoSecrets_example.py

This plugin, like every CliveS Indigo plugin, reads sensitive values from one shared master file:

/Library/Application Support/Perceptive Automation/IndigoSecrets.py

File	Purpose	Real data?	Committed to GitHub?
IndigoSecrets.py	Working file the plugin reads at runtime. Keep a backup in a password manager.	YES	NO — listed in .gitignore
IndigoSecrets_example.py	Template only — empty placeholders. Shipped in the plugin bundle.	NO	YES

If you don't have IndigoSecrets.py, copy IndigoSecrets_example.py out of the plugin bundle into /Library/Application Support/Perceptive Automation/, rename it to IndigoSecrets.py, and fill in your values. Or skip the file altogether and type the values into the plugin's configuration dialog — where both are set, IndigoSecrets.py wins.

If neither source supplies a value the plugin needs, it logs an ERROR naming the key and telling you to either fill in the matching field or add the key to IndigoSecrets.py.

Keys read by TariffAnalyser:

OCTOPUS_API_KEY       = "sk_live_..."
OCTOPUS_MPAN          = ""
OCTOPUS_SERIAL        = ""
OCTOPUS_EXPORT_MPAN   = ""   # optional — export tariff comparisons
OCTOPUS_EXPORT_SERIAL = ""
OCTOPUS_GAS_MPRN      = ""   # optional — gas cost calculations
OCTOPUS_GAS_SERIAL    = ""

Each key has a matching field under Plugins → Tariff Analyser → Configure (see Plugin Configuration below) so the plugin can be set up entirely via the GUI for users who don't maintain IndigoSecrets.py. (PluginConfig fallback added in v1.3.)

Output

The plugin writes reports to:

/Library/Application Support/Perceptive Automation/TariffAnalyser/

Each one is an HTML file named tariff_comparison_<from>_<to>_<timestamp>.html, and the plugin hands it to macOS to open, so it lands in your default browser.

Usage

Menu Items (Indigo → Plugins → Tariff Analyser)

Menu item	What it does
Energy Summary	Savings summary (today / yesterday / this week / month / year) as an HTML page in your browser
Tariff Comparison	Choose a lookback period, then it ranks every tariff by what your real usage would have cost and opens the HTML report
Test Octopus API Connection	Checks the Agile products endpoint, the discovered import/export product codes for your region, and cached-price coverage
Toggle Timestamps in Log	Turns the [HH:MM:SS.mmm] log prefix on or off
Show Plugin Info	Displays plugin version, paths, region, and credential status

Schedulable Actions

Action	Description
Generate Report	Generates a comparison report for the last N days
Update Prices	Fetches missing Agile prices
Update Daily Summary	Refreshes the rolling daily_summary from the Octopus API
Energy Summary	Regenerates and opens the savings summary

Tariffs Covered

Import

Key	Tariff	Type
tracker	Octopus Tracker	Actual per-slot prices from DB
go	Octopus Go	5h cheap window 00:30–05:30
go_faster	Octopus Go Faster	6h cheap window 23:30–05:30
agile	Octopus Agile	Half-hourly variable, auto-fetched
cosy	Octopus Cosy	Two 3h cheap windows + peak
flux	Octopus Flux	3h cheap window 02:00–05:00 + 3h peak 16:00–19:00
economy7	Economy 7	7h night rate
ofgem_cap	Ofgem SVT Price Cap	Single flat rate
eon_fixed	E.ON Next Fixed	Typical fixed rate
edf_fixed	EDF Fixed	Typical fixed rate
scottishpower_fixed	Scottish Power Fixed	Typical fixed rate

Export

Key	Tariff
outgoing_12p	Octopus Outgoing 12p flat
agile_outgoing	Octopus Agile Outgoing (variable)
seg_min	SEG Minimum (Ofgem floor, 1.63p)
seg_typical	SEG Typical (e.g. EDF/E.ON, 7.5p)

Plugin Configuration

Open it from Indigo → Plugins → Tariff Analyser → Configure:

Field	Default	Description
Timeseries DB path	Auto (SigenEnergyManager prefs)	Path to energy_timeseries.db
Output folder	Auto (/Library/.../TariffAnalyser)	Where HTML reports are saved
Open report after scheduled run	Off	Opens the report once a schedule or action generates it
Octopus region	F (North East England)	Used for Agile price lookups
Export tariff	Octopus Outgoing 12p	Applied to all import tariff comparisons
Default date range	Last 30 days	Default for scheduled action
Octopus API key	(blank)	Fallback for IndigoSecrets.OCTOPUS_API_KEY
Import MPAN	(blank)	Fallback for IndigoSecrets.OCTOPUS_MPAN
Import meter serial	(blank)	Fallback for IndigoSecrets.OCTOPUS_SERIAL
Export MPAN	(blank)	Fallback for IndigoSecrets.OCTOPUS_EXPORT_MPAN
Export meter serial	(blank)	Fallback for IndigoSecrets.OCTOPUS_EXPORT_SERIAL
Gas MPRN	(blank)	Fallback for IndigoSecrets.OCTOPUS_GAS_MPRN
Gas meter serial	(blank)	Fallback for IndigoSecrets.OCTOPUS_GAS_SERIAL

Logging

Every log line carries a millisecond timestamp [HH:MM:SS.mmm], so you can line events up precisely against the other CliveS plugins — Device Activity Monitor uses the same format.

To turn the prefix off, or back on, at any time:

Plugins → Tariff Analyser → Toggle Timestamps in Log (on/off)

The plugin stores the setting in pluginPrefs (timestampEnabled) and it survives a restart. It defaults to ON.

Version history

v1.9.3 — Added the missing support link. Every Indigo plugin is meant to carry a web address inside its bundle — it is what the "About" item in the Plugins menu opens. This one had the entry but left it blank, so that menu item went nowhere. It now points at this repository. Nothing else changed.

• 1.9.1–1.9.2 (21-07-2026) — housekeeping pair. Named log levels now map to the real logging levels — warnings and errors raised through the shared helper had been appearing as plain info lines, so amber and red entries people relied on for diagnosis never showed. Shared-utility refresh: calling the log timestamp filter twice no longer double-stamps every line, and the module imports cleanly outside Indigo.
• 1.9 (18-07-2026) — deep-review improvements: a Test Octopus API Connection menu item, and the report now states when the illustrative "typical" fixed tariffs were last checked (Tracker and Agile always use live rates).
• 1.8 (18-07-2026) — deep-review test buildout: 27 tests covering the comparison arithmetic and the collector's time-of-use, gas and timezone helpers.
• 1.7 (18-07-2026) — deep-review financial fixes. Tariffs are now ranked fairly over a common set of half-hourly slots so a tariff with patchy price data can no longer appear cheapest just because part of your usage was never counted. A missing Tracker rate no longer records a false £0 day, the Go and Flux "saving vs Tracker" figures now include the standing-charge difference, and the Octopus fetch windows were widened so the first slots of a day are not lost in British Summer Time. First test suite added.
• 1.6 (10-06-2026) — housekeeping. Lint clean-up and a continuous-integration check added as part of a fleet-wide audit. No change in behaviour.
• 1.5 (05-06-2026) — estate bug-sweep. Opening the report automatically after a scheduled run called a function that no longer existed, so that option failed every time it was used. The coverage lookup now catches only database errors, letting genuine programming mistakes surface rather than hiding them.
• 1.4 (23-05-2026) — millisecond timestamp [HH:MM:SS.mmm] prefix on every self.logger line via plugin_utils.install_timestamp_filter(); new "Toggle Timestamps in Log" menu item.
• 1.3 (23-05-2026) — PluginConfig fallback for all 7 Octopus credential keys; secrets-policy compliance. IndigoSecrets.py still takes precedence when set.
• 1.2 — current SigenEnergyManager integration; daily auto-update at 02:00.

Authors & licence

Vibed into existence by CliveS, who knew what he wanted, argued until he got it, and tested it on a real house. Typed at inhuman speed by Claude (Anthropic), who mostly did as it was told.

© 2026 CliveS · MIT licence — copy it, fork it, bend it, break it, fix it, ship it. If it breaks, you get to keep both pieces.