diff --git a/homeassistant/components/watttime/icons.json b/homeassistant/components/watttime/icons.json
new file mode 100644
index 00000000000..e4c9cfa4f5b
--- /dev/null
+++ b/homeassistant/components/watttime/icons.json
@@ -0,0 +1,12 @@
+{
+  "entity": {
+    "sensor": {
+      "marginal_operating_emissions_rate": {
+        "default": "mdi:blur"
+      },
+      "relative_marginal_emissions_intensity": {
+        "default": "mdi:blur"
+      }
+    }
+  }
+}
diff --git a/homeassistant/components/watttime/sensor.py b/homeassistant/components/watttime/sensor.py
index ca5b0d06fa2..93560cef808 100644
--- a/homeassistant/components/watttime/sensor.py
+++ b/homeassistant/components/watttime/sensor.py
@@ -38,14 +38,12 @@ REALTIME_EMISSIONS_SENSOR_DESCRIPTIONS = (
     SensorEntityDescription(
         key=SENSOR_TYPE_REALTIME_EMISSIONS_MOER,
         translation_key="marginal_operating_emissions_rate",
-        icon="mdi:blur",
         native_unit_of_measurement=f"{UnitOfMass.POUNDS} CO2/MWh",
         state_class=SensorStateClass.MEASUREMENT,
     ),
     SensorEntityDescription(
         key=SENSOR_TYPE_REALTIME_EMISSIONS_PERCENT,
         translation_key="relative_marginal_emissions_intensity",
-        icon="mdi:blur",
         native_unit_of_measurement=PERCENTAGE,
         state_class=SensorStateClass.MEASUREMENT,
     ),