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docs/card-power.md

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+# Power Card (v3.9 and higher)
+
+![card-power](img/card-power.png)
+
+```yaml
+    cards:
+      - type: cardPower
+        title: Power Test
+        entities:
+          - entity: sensor.today_energy
+          - entity: delete
+          - entity: sensor.today_energy
+            speed: 3
+          - entity: sensor.today_energy
+            speed: -1
+          - entity: sensor.today_energy
+            speed: -2
+          - entity: sensor.today_energy
+            speed: -3
+          - entity: sensor.today_energy
+            speed: 1
+          - entity: sensor.today_energy
+            speed: 1
+```
+
+The first two entities are shown in the middle of the card, all other entities are used around it.
+
+List of supported config keys of this card:
+
+key | optional | type | default | description
+-- | -- | -- | -- | --
+`type` | False | string | `None` | Used by navigate items
+`entities` | False | complex | `None` | contains entities of the card
+`title` | True | string | `None` | Title of the Page 
+`key` | True | string | `None` | Used by navigate items
+
+List of supported entitiy types for this page:
+
+- sensor
+
+Some details about speed:
+
+It is possible to calculate the speed though home assistant templates, this allows to link the speed to something within your homeassistant.
+
+If you got a proper configuration for that, feel free to share it, would be a good addition to the documentation.
+
+```
+          - entity: sensor.today_energy
+            speed: '{{ range(-3, 3) | random }}'
+```
+