Hi, i was thinking about how to use my ESS System during winter and created a little script to charge the battery depending the spot market prices (Epex hourly).
Victron-ESS & Shelly Plug S & AVM-Fritz-DECT200-210 Spotmarket-Switcher
https://github.com/christian1980nrw/Spotmarket-Switcher
Shell script that manages Victron Venus OS ESS-Systems & Shelly Plug S & AVM Fritz!DECT200 / 210 switchable sockets so that it charges / switches, when spot-market prices at Tibber or Awattar are low.
If you like you can also activate additional load (like water heater) by using AVM FRITZ!DECT 200 or 210 switchable sockets. If you have spot-market energy prices, you are able to charge your battery if the price is lower than your own feed-in tariff or you can use cheap prices of wind energy at night.
This allows you to use your battery even in winter without sun.
You need a hourly based dynamic tariff for this but of course you are able to test this script before
you change your provider and think about a smart meter.
The prices (EPEX Spot DE-LU/AT hourly prices) are from a german energy provider. Since v0.8 a second free API from Entso-E with all european countrys is supported.
You can compare the prices here:
https://transparency.entsoe.eu/transmission-domain/r2/dayAheadPrices/show
Edit: v0.1 with some fixes is released now, please update.
Edit2: v0.2 Added some more charging hours, please update.
Edit3: v0.3 Added some improvements
Edit4: v0.4 Additional load by switch socket can be activated independent of charging now
Edit5: v0.5 code cleanups & bugfixes done
Edit6: v0.6 possibility to enter decimal points, added third charging logic, extended possible switchable sockets to six
Edit7: v0.7 Ability to abort nightly charging if enough sun is expected
Edit8: v0.8 Whole Europe is supported now
Edit9: v0.9 Code cleanups, please update
Edit10: v1.0 Solar API improvements, please update
Edit11: v1.1 Fixed Bug with single-digit calendar days, please update
Edit12: v1.2 Code cleanup / optimized Script runtime by using awk
v1.3 Added a Venus OS Installer script (should survive Firmware upgrades)
v1.5 Bugfix of Venus OS Installer (run script)
Edit 13:
v1.7 Added switching logfile / fixed bug #2
v1.8 Consideration of charger efficiency / Support of Shelly Plug S Wifi switchable socket
v1.9 Fix of Awattar API issue/bug #3
v2.0 new Entso-E API endpoint, please update.
The old REST API endpoint is planned to be discontinued by Entso-E on 14.02.2023.
v2.1 Tibber API integration & Entso-E API bugfix
Release notes see https://github.com/christian1980nrw/Spotmarket-Switcher/blob/main/release_notes.md Thanks to moeller@debian.org for joining the project. I appreciate it.
Please update as soon as possible.
v2.2 Consider battery life cycle costs, Added economic charge-check based on average prices
Fixed Tibber abort price calculation
If you live in Germany and would like to switch to a dynamic electricity tariff, you can support me and take out the tariff via the following link. We both get a 50 euro bonus for hardware. https://invite.tibber.com/ojgfbx2e In the tibber app, click at "i was invited" and enter the code ojgfbx2e in the app. Please note that you need a smart meter or a tracker like Pulse https://tibber.com/de/store/produkt/pulse-ir for a hourly tariff. Enter the first 4 digits of your meter number on that website to check Pulse compatibility.
Thanks and regards, Christian