homebridge-wattwatchers v0.0.2

Wattwatchers Homebridge Plugin

This is a plugin for Homebridge. It exposes Solar generation data from your Wattwatchers device as well as your device's switches to HomeKit.

Installation for development purposes

1. Clone or download the repository
2. In your terminal, navigate to the repository directory and execute the command npm link
3. Homebridge should now be aware of the plugin.

Regular installation

1. In Homebridge, select the Plugins tab.
2. Search for Wattwatchers.
3. Click 'Install' on the Wattwachers plugin card.

Plugin configuration

1. In Homebridge, select the Plugins tab.

2. Select Settings on the Homebridge Wattwatchers plugin

3. Sign in with your MyEnergy.Data credentials

4. Configure the plugin by selecting a site and setting the polling interval (this is the interval between API requests for switch states and excesss solar energy)

The plugin will automatically expose all available switches to HomeKit as Garage Door Openers. Switch states are mapped to Garage Door Opener state as follows:

5. If the selected site has solar, you will also be able to configure an excess solar sensor. This will be exposed to HomeKit as an Occupancy Sensor. The configuration has 4 parameters:

   - The amount of excess solar (in Watts) required for switching ON (i.e. setting the Occupancy Sensor to "Occupancy Detected")
   - The amount of excess solar (in Watts) required for switching OFF (i.e. setting the Occupancy Sensor to "No Occupancy Detected")
   - The minimum duration (in minutes) to remain ON (i.e. keeping the Occupancy Sensor in the "Occupancy Detected" state, regardless of the excess solar available)
   - The minimum duration (in minutes) to remain OFF (i.e. keeping the Occupancy Sensor in the "No Occupancy Detected" state, regardless of the excess solar available)

The minimum duration parameters can be used to prevent loads switching ON and OFF quickly, which may be detrimental to devices like pool pumps. For the same reason it is further advisable to make the difference between the amounts of excess solar required for switching ON and OFF larger than the load you are planning to trigger based on the sensor value.

Example

Alex has a pool with a 1100 Watt pool pump and wants to only use excess solar energy to run it.

Alex uses the following configuration:

• excess solar required to switch ON: 1400W
• excess solar required to switch OFF: 0W
• minimum duration to remain ON: 30 minutes
• minimum duration to remain OFF: 30 minutes

The difference between excess solar required to switch ON and OFF (1400W) is larger than the load of the pool pump (1100W), so switching won't be too "twitchy"

The excess solar required to switch ON (1400W) is also larger than the load of the pool pump (1100W) too build in a bit of buffer so a small drop in solar generation won't mean the pump will start consuming grid electricity.

Despite the buffers in this configuration it is possible the pool pump will use grid electricity if solar generation drops substantially during the first 30 minutes after the pool pump is turned on.

Creating automations

The configured switches and sensor will be available within the HomeKit app.

Here they can be used to build automations (e.g. turn on the pool pump when the occcupancy sensor is in the "Occupancy Detected" state, indicating that enough excess solar is available.)

For instructions on how to create automations, visit Apple