Add documentation for ComEd Hourly Pricing sensor (#2186)

source/_components/sensor.comed_hourly_pricing.markdown

@@ -0,0 +1,37 @@
+---
+layout: page
+title: "ComEd Hourly Pricing"
+description: "Instructions how to set up the ComEd Hourly Pricing sensor in Home Assistant."
+date: 2017-03-02 0:15
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: comed.jpg
+ha_category: Energy
+ha_release: 0.40
+ha_iot_class: "Cloud Polling"
+---
+
+The ComEd Hourly Pricing program is an optional program available to ComEd electric subscribers which charges customers a variable rate for electricity supply based on current demand rather than a traditional fixed rate.  Live prices are published [here](https://hourlypricing.comed.com/live-prices/) and also via an [API](https://hourlypricing.comed.com/hp-api/) which we can integrate as a sensor in Home Assistant.
+
+There are two price feeds available: the 5-minute price and current hour average price.
+
+```yaml
+# Example configuration.yaml entry
+sensor:
+  - platform: comed_hourly_pricing
+    monitored_feeds:
+      - type: five_minute
+      - type: current_hour_average
+```
+
+Configuration variables:
+
+- **monitored_feeds** array (*Required*): Feeds to monitor.
+  - **type** (*Required*): Name of the feed.
+      - **five_minute**: The latest 5-minute price in cents.
+      - **current_hour_average**: The latest current hour average price in cents.
+  - **name** (*Optional*): Custom name for the sensor.
+  - **offset** (*Optional*): The pricing feeds provide only the *supply* cost of the electricity.  The offset parameter allows you to provide a fixed constant that will be added to the pricing data to provide a more accurate representation of the total electricity cost per kWh.
+