Sacramento Municipal Utility District (SMUD) docs (#31874)

* Create smud.markdown

* Update opower.markdown

source/_integrations/opower.markdown

@@ -43,6 +43,7 @@ More than 175 utilities use Opower. Currently only the following utilities are s
 - Pacific Gas & Electric (PG&E)
 - Portland General Electric (PGE)
 - Puget Sound Energy (PSE)
+- Sacramento Municipal Utility District (SMUD)
 - Seattle City Light (SCL)
 
 When you add the Opower integration to Home Assistant, you will need to provide your utility account's authentication details to enable retrieving your energy data.

source/_integrations/smud.markdown

@@ -0,0 +1,20 @@
+---
+title: Sacramento Municipal Utility District (SMUD)
+description: Get energy usage from Sacramento Municipal Utility District (SMUD) using the Opower integration
+ha_category:
+  - Energy
+  - Sensor
+ha_release: 2024.4
+ha_domain: smud
+ha_integration_type: virtual
+ha_supporting_domain: opower
+ha_supporting_integration: Opower
+ha_codeowners:
+  - '@tronikos'
+ha_config_flow: true
+ha_platforms:
+  - sensor
+ha_iot_class: Cloud Polling
+---
+
+{% include integrations/supported_brand.md %}