0.0.5 • Published 6 months ago

homebridge-epex v0.0.5

Weekly downloads
-
License
Apache-2.0
Repository
github
Last release
6 months ago

EPEX day ahead electricity price in Homebridge

!IMPORTANT NOTE: WIP

This plugin will get energy prices (electricity) in Europe via the EPEX day ahead spot price (https://www.epexspot.com/en) published via the public ENTSO-E transparency platform (https://transparency.entsoe.eu).

The plugin will publish the EPEX Energy Price data (updated hourly) as a "temperature" sensor. The idea is that it can subsequently be used in HomeKit Automations to control other acessories.

If no EPEX Energy Price can be retrieved a default value (100, configureable) will be published.

EPEX Electricity price data access and this plugin

!IMPORTANT This Homebridge plugin requires that you obtain your own API security token on ENTSO-E in order to access the data. It is free (as in free beer) and easy enough but takes some time to do.

Instructions here: (https://transparencyplatform.zendesk.com/hc/en-us/articles/12845911031188-How-to-get-security-token)


Installation

The easiest installation method is to use Homebridge Configuration UI and search for this plugin.

EPEX Day-ahead energy price data

The ENTSO-E API returns energy price data in the units EUR/MWh without any local taxes (e.g. VAT etc.). Because this plugin is mainly for domestic use the energy price is converted to EUR/kWh.

In the Netherlands in 2025 you pay the following additional costs (which are in fact much higher than the actual energy price):

  • Purchasing fee for the Utility company: typically 2 ct/kWh
  • National Energy Tax: 6.9 ct/kWh (2025)
  • VAT: 21% on the alreay taxed amount.

So, if EPEX is 0.0 ct/kWh (so free energy) you still pay (6.9 + 2) * 1.21 = 10.7 ct/kWh.

Because EPEX can become negative it is interesting to know when the net, actual, price you pay the utility is also negative. In the Netherlands (2025) this happens at EPEX prices lower than -9 ct/kWh. At that point dynamic pricing energy is actually really free for the end consumer (while you still pay taxes...).

Configuration

Country - EIC Bidding Zone

You need to configure the region/country from which you want to get the EPEX Energy Price data. This is called the Bidding Zone EIC information and you can get the codes you need here: (https://transparencyplatform.zendesk.com/hc/en-us/articles/15885757676308-Area-List-with-Energy-Identification-Code-EIC)

For example for the Netherlands, use: BZN|NL

Country - EIC Bidding Zone

You need to obtain your own API security token on ENTSO-E in order to access the data. It is free (as in free beer) and easy enough but takes some time to do.

Instructions here.

Configuration Summary

OptionTitleTypeRequiredDefaultDescription
nameNamestringYesEPEX Energy Price MonitorThe name of your accessory as it will appear in Homebridge/HomeKit.
refreshIntervalRefresh Interval (minutes)integerNo15How often (in minutes) to poll ENTSO-E for updated price data. The minimum recommended is 15.
in_DomainCountry / In-Domain (Bidding Zone)stringYes10YNL----------LThe ENTSO-E Bidding Zone Code representing the receiving energy area.
apiKeyENTSO-E API KeystringYes(empty)If your ENTSO-E account requires an API key, enter it here.
max_priceMaximum PriceintegerNo100Fallback for the maximum energy price if data is missing. Cannot exceed 100.

Changelog

version 0.0.5

  • handle incomplete data returned from the ENTSOE API, e.g.: Energy Prices 12.1.D not available for 20th January on TP 20.01.2025 12:04 https://transparency.entsoe.eu/news/widget?id=678e3a6bc3645d7db0416fbd
  • only log on the hour (on price change), less spam in the logs
  • removed option to set fallback price in case of errors, always use max allowed (100)
  • expanded debug logs and cleaned up
  • remove namespace.

version 0.0.3

  • initial release
  • cleanup logging