Before submitting an issue, search the issues and discussion forum to see if this has already been ask and answered in the past. The following usually fixes most users problems...

• make sure the API key you enter is the API key and not the rooftop id
• make sure the solcast toolkit area is working
• READ THE LOG OUTPUT, this gives some good info as to whats happening or a problem
• make sure your not out of API calls
• if all that fails run the service to delete the solcast data file (or manually delete it from HA/config/solcast.json and restart HA)

Home Assistant(https://www.home-assistant.io) Integration Component

This custom component integrates the Solcast Hobby PV Forecast API into Home Assistant.

⚠️ Solcast have altered their API limits for new account creators

Solcast now only offer new account creators 10 api calls per day (used to be 50). 
Old account users still have 50 api calls

The integration now no longer includes auto api polling. Users now need to create their own automations
to call the update solcast service to poll for new data. Keep in mind your API poll limit.

Sign up for an API key (https://solcast.com/)

Solcast may take up to 24hrs to create the account

Copy the API Key for use with this integration (See Configuration below).

Using HACS. More info here

Manually in HACS
Follow the link here
Use the custom repo link https://github.com/oziee/ha-solcast-solar
Select the category type integration
Then once it's there (still in HACS) click the INSTALL button
Then go to the HA Devices and Services and add a new Solcast Integration

You probably do not want to do this! Use the HACS method above unless you know what you are doing and have a good reason as to why you are installing manually

1. Using the tool of choice open the directory (folder) for your HA configuration (where you find configuration.yaml)
2. If you do not have a custom_components directory there, you need to create it
3. In the custom_components directory create a new folder called solcast_solar
4. Download all the files from the custom_components/solcast_solar/ directory in this repository
5. Place the files you downloaded in the new directory you created
6. Restart HA to load the new integration
7. See Configuration below

1. Click Here to directly add a Solcast Solar integration or
   a. In Home Assistant, go to Settings -> Integrations
   b. Click + Add Integrations and select Solcast PV Forecast
   
2. Enter you Solcast API Key
3. Click Submit

• Create your own automation to call the service solcast_solar.update_forecasts when you like it to call

• Options can be changed for existing Solcast PV Forecast integration in Home Assistant Integrations by selecting Configure (cog wheel)

• If you have more than one Solcast account because you have more than 2 rooftop setups, enter both account API keys seperated by a comma xxxxxxxx-xxxxx-xxxx,yyyyyyyy-yyyyy-yyyy (this does go against Solcast T&C's having more than one account)

• This is your API Key not your rooftop id created in Solcast. You can find your API key here api key

New in v4.0.8 is the option to configure hourly dampening values

Here you can change the dampening factor value for any hour. Values from 0.0 - 1.0 are valid. Setting 0.95 will dampen each Solcast forecast data value by 5%. This is reflected in the sensor values and attributes and also in the graphical energy dash board

There are 3 services for this integration that you can use in automations (Configuration)

Create a new HA automation and setup your prefered triggers to manually poll for new data
These are examples.. alter these or create your own to fit your own needs

alias: Solcast_update
description: New API call Solcast
trigger:
 - platform: time_pattern
   hours: /4
condition:
 - condition: sun
   before: sunset
   after: sunrise
action:
 - service: solcast_solar.update_forecasts
   data: {}
mode: single

or

alias: Solcast update
description: ""
trigger:
  - platform: time
    at: "4:00:00"
  - platform: time
    at: "10:00:00"
  - platform: time
    at: "16:00:00"
condition: []
action:
  - service: solcast_solar.update_forecasts
    data: {}
mode: single

To make the most of the available API calls, you can call the API in an interval calculated by the number of daytime hours by the number of total API calls a day:

alias: Solcast update
description: ""
trigger:
  - platform: template
    value_template: >-
      {% set nr = as_datetime(state_attr('sun.sun','next_rising')) | as_local %}
      {% set ns = as_datetime(state_attr('sun.sun','next_setting')) | as_local %}
      {% set api_request_limit = 10 %}
      {% if nr > ns %}
        {% set nr = nr - timedelta(hours = 24) %} 
      {% endif %}
      {% set hours_difference = (ns - nr) %}
      {% set interval_hours = hours_difference / api_request_limit %}
      {% set ns = namespace(match = false) %}
      {% for i in range(api_request_limit) %}
        {% set start_time = nr + (i * interval_hours) %}
        {% if ((start_time - timedelta(seconds=30)) <= now()) and (now() <= (start_time + timedelta(seconds=30))) %}
          {% set ns.match = true %}
        {% endif %}
      {% endfor %}
      {{ ns.match }}
condition:
  - condition: sun
    before: sunset
    after: sunrise
action:
  - service: solcast_solar.update_forecasts
    data: {}
mode: single

Note If you have two arrays on your roof then 2 api calls will be made for each update, effectively reducing the number of updates to 5 per day. For this case, change to: api_request_limit = 5

Go to the HA>Settings>Dashboards>Energy Click the edit the Solar Production item you have created.

Note If you do not have a solar sensor in your system then this integration will not work. The graph, and adding the forecast integration rely on there being a sensor setup to be added here

Click the Forecast option button and select the Solcast Solar option.. Click SAVE.. HA will do all the rest for you

Modified from the great works of

• @rany2 - ranygh@riseup.net
• dannerph/homeassistant-solcast
• cjtapper/solcast-py
• home-assistant-libs/forecast_solar