feature: add automatic switching to grid usage when energy free or ne…

…gative cost, add automatic excess energy export/sale at the most profitable hour of each day

lib/constants.py

@@ -58,10 +58,12 @@ def dotenv_config(env_variable):
             "system_shutdown":                  f"Cerbomoticzgx/system/shutdown",
 
             # Tibber
-            "tibber_total":         f"N/{systemId0}/Tibber/home/energy/day/euro_day_total",  # workaround to update dz
-            "tibber_day_total":     f"Tibber/home/energy/day/reward",
-            "tibber_last_update":   f"Tibber/home/energy/day/last_update",
-            "tibber_price_now":     f"Tibber/home/price_info/now/total",
+            "tibber_total":                 f"N/{systemId0}/Tibber/home/energy/day/euro_day_total",  # workaround to update dz
+            "tibber_day_total":             f"Tibber/home/energy/day/reward",
+            "tibber_last_update":           f"Tibber/home/energy/day/last_update",
+            "tibber_price_now":             f"Tibber/home/price_info/now/total",
+            "tibber_cost_highest_today":    f"Tibber/home/price_info/today/highest/0/cost",
+            "tibber_cost_lowest_today":     f"Tibber/home/price_info/today/lowest/0/cost",
 
             # Tesla specific metrics
             "tesla_power":          f"N/{systemId0}/acload/40/Ac/Power",

lib/energy_broker.py

@@ -10,10 +10,13 @@
 from lib.notifications import pushover_notification
 from lib.tibber_api import publish_pricing_data
 from lib.global_state import GlobalStateClient
+from lib.victron_integration import ac_power_setpoint
+
 
 MAX_TIBBER_BUY_PRICE = float(dotenv_config('MAX_TIBBER_BUY_PRICE')) or None
 STATE = GlobalStateClient()
 
+
 def main():
     logging.info("EnergyBroker: Initializing...")
 
@@ -26,6 +29,10 @@ def main():
 def scheduler_loop():
     def is_alive():
         logging.info(f"EnergyBroker: heartbeat...thumpThump!")
+
+        # updating the hourly price is normally triggered on batter_soc changes.  Since this will not happen when
+        # battery is full and idle, we check for that condition here and still update the hourly price at 5 minute
+        # intervals.
         if dotenv_config('TIBBER_UPDATES_ENABLED') == '1' and STATE.get('batt_soc') == 100.0:
             publish_pricing_data(__name__)
 
@@ -40,6 +47,43 @@ def is_alive():
         scheduler.run_pending()
         time.sleep(1)
 
+def manage_sale_of_stored_energy_to_the_grid(batt_soc: float) -> None:
+    tibber_price_now = STATE.get('tibber_price_now')
+    tibber_24h_high = STATE.get('tibber_cost_highest_today')
+    ac_setpoint = STATE.get('ac_power_setpoint')
+
+    if batt_soc > 80.0 and tibber_price_now >= tibber_24h_high and tibber_price_now != 0:
+        if ac_setpoint != -10000.0:
+            ac_power_setpoint(watts="-10000.0")
+            logging.info(f"Beginning to sell energy at a cost of {round(tibber_price_now, 3)}")
+            pushover_notification("Energy Sale Alert",
+                                  f"Beginning to sell energy at a cost of {round(tibber_price_now, 3)}")
+    else:
+        if ac_setpoint < 0.0:
+            ac_power_setpoint(watts="0.0")
+            logging.info(f"Stopped energy export at {batt_soc} and a current price of {round(tibber_price_now, 3)}")
+            pushover_notification("Energy Sale Alert",
+                                  f"Stopped energy export at {batt_soc} and a current price of {round(tibber_price_now, 3)}")
+
+
+def manage_grid_usage_based_on_current_price(price: float) -> None:
+    inverter_mode = int(STATE.get("inverter_mode"))
+
+    # if energy is free or the provider is paying, switch to using the grid and start vehicle charging
+    if price <= 0.0001 and inverter_mode == 3:
+        pushover_notification("Tibber Price Alert",
+                              f"Energy cost is {round(price, 3)} cents per kWh. Switching to grid energy.")
+        Utils.set_inverter_mode(mode=1)
+        return
+
+    # revese the above action when energy is no longer free
+    if price >= 0.0001 and inverter_mode == 1:
+        print(inverter_mode)
+        pushover_notification("Tibber Price Alert",
+                              f"Energy cost is {round(price, 3)} cents per kWh. Switching back to battery.")
+        Utils.set_inverter_mode(mode=3)
+        return
+
 def publish_mqtt_trigger():
     publish.single("Cerbomoticzgx/EnergyBroker/RunTrigger", payload=f"{{\"value\": {time.localtime().tm_hour}}}", qos=0, retain=False,
                    hostname=cerboGxEndpoint)

lib/event_handler.py

@@ -7,10 +7,14 @@
 from lib.constants import dotenv_config, logging, cerboGxEndpoint
 from lib.victron_integration import regulate_battery_max_voltage
 from lib.tibber_api import publish_pricing_data
-from lib.energy_broker import set_48h_charging_schedule, Utils
 from lib.global_state import GlobalStateClient
-from lib.notifications import pushover_notification
 from lib.tesla_api import TeslaApi
+from lib.energy_broker import (
+    manage_sale_of_stored_energy_to_the_grid,
+    set_48h_charging_schedule,
+    manage_grid_usage_based_on_current_price
+)
+
 
 tesla = TeslaApi()
 
@@ -33,12 +37,11 @@ def __init__(self, mqtt_topic, value, logging_msg=None):
 
     def dispatch(self):
         try:
-            # Update Global State db even if the method is not handled explicitly within the scope of
-            # this event handler.
-            self.gs_client.set(self.topic_key, self.value)
-
             if self.topic_key:
-                # call the method which matches self.topic_key
+                # Update the Global State db even if we do not have an explicit method defined for this topi_key
+                self.gs_client.set(self.topic_key, self.value)
+
+                # if a method is defined, call it. Otherwise, call _unhandled_method()
                 getattr(self, self.topic_key, self._unhandled_method)()
                 logging.debug(f"{self.topic_key} method")
             else:
@@ -53,20 +56,7 @@ def _unhandled_method(self):
 
     def tibber_price_now(self):
         _value = float(self.value)
-        inverter_mode = int(self.gs_client.get("inverter_mode"))
-        vehicle_is_charging = bool(self.gs_client.get("tesla_is_charging"))
-        vehicle_is_plugged = bool(self.gs_client.get("tesla_plug_status"))
-
-        # if energy is free or the provider is paying, switch to using the grid and start vehicle charging
-        if _value <= 0.0001 and inverter_mode == 3:
-            pushover_notification("Tibber Price Alert", f"Energy cost is {round(_value, 3)} cents per kWh. Switching to grid energy.")
-            Utils.set_inverter_mode(mode=1)
-
-        # revese the above action
-        if _value >= 0.0001 and inverter_mode == 1:
-            print(inverter_mode)
-            pushover_notification("Tibber Price Alert", f"Energy cost is {round(_value, 3)} cents per kWh. Switching back to battery.")
-            Utils.set_inverter_mode(mode=3)
+        manage_grid_usage_based_on_current_price(_value)
 
     def system_shutdown(self):
         _value = self.value
@@ -93,6 +83,7 @@ def batt_soc(self):
             regulate_battery_max_voltage(_value)
         if dotenv_config('TIBBER_UPDATES_ENABLED') == '1':
             publish_pricing_data(__name__)
+            manage_sale_of_stored_energy_to_the_grid(_value)
 
     def batt_power(self):
         _value = round(self.value)

lib/victron_integration.py

@@ -2,17 +2,21 @@
 import paho.mqtt.publish as publish
 import paho.mqtt.subscribe as subscribe
 
+from lib.global_state import GlobalStateClient
+
 from lib.constants import logging, cerboGxEndpoint, Topics, TopicsWritable, dotenv_config
 
 
+STATE = GlobalStateClient()
 float_voltage = float(dotenv_config('BATTERY_FLOAT_VOLTAGE'))
 max_voltage = float(dotenv_config('BATTERY_ABSORPTION_VOLTAGE'))
 battery_full_voltage = float(dotenv_config('BATTERY_FULL_VOLTAGE'))
 
 def ac_power_setpoint(watts=None):
     if watts:
         _msg = f"{{\"value\": {watts}}}"
-        logging.info(f"Victron Integration: Setting AC Power Set Point to: {watts} watts")
+        logging.debug(f"Victron Integration: Setting AC Power Set Point to: {watts} watts")
+        STATE.set(key='ac_power_setpoint', value="0.0")
         publish.single(TopicsWritable['system0']['ac_power_setpoint'], payload=_msg, qos=0, retain=False, hostname=cerboGxEndpoint, port=1883)
 
 def minimum_ess_soc(percent: int = 10):