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{{:tech-explained:solar-sid-solcast-easy-setup.jpg?nolink&800|What is Solcast? & How to set it up}}

====== What is Solcast? - The Solar Sid Version ======

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Think of Solcast as a weather forecast, but just for your solar panels.

You know how Met Éireann tells you if it's going to rain tomorrow? Well, Solcast tells you how much FREE electricity your roof is going to make tomorrow.

It looks at the clouds, the sun, your location, which way your panels face, and how big your system is, and then it says: "Tomorrow your roof will make about 20kWh."

So you can plan ahead, simples.

Instead of guessing whether to run the washing machine or heat the immersion tonight, you actually know if the sun will do it for free tomorrow.

It's made by a bunch of clever Aussies, it's used by the big energy companies, but they give a free version to normal people like us with houses - that's the Hobbyist / Home User account.

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💡 **In short:** It stops you paying for electricity that the sun was going to give you for nothing.
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Here is how to set it up; it's so easy anyone can do it.

===== STEP 1: Register - Become a Solcast-away =====

    1. Go to: **toolkit.solcast.com.au/register**
    2. You will see 3 big options. Click the big **‘Home User’** button on the bottom left. Not Commercial, unless you own a solar farm and didn't tell us.
    3. It takes you to a page that says "Tell us a little about you" - sounds a bit creepy, but carry on.
        * Account type: Select **Hobbyist** - sounds better than "I just want free stuff"
        * Name, email, location
        * Agree to terms and hit **Submit**
    4. It will ask you to set a password. Make it something you won't forget. Not ''solar123''.

===== STEP 2: Activate and Log In - Watt are you waiting for? =====

    1. Check your email. Solcast will send you an activation email. If you can't find it, check spam. It's not *shading* you on purpose.
    2. Click the link, log in.
    3. You land on the **Home PV Systems dashboard**. Click **‘Add your first Home PV system to get started’**.

You are now officially more powerful than the ESB. Well, almost.

===== STEP 3: Add Your Solar System - The Techy Bit (Don't get dis-panel-ed) =====

This is where you tell Solcast what you've got on your roof.

    * **Site Name:** "My House in Carlow" or "The Money Saver 3000"
    * **Location:** Drop a pin on your house. Be accurate, or it'll forecast sunshine for your neighbour.
    * **Capacity AC (Inverter kW):** Look at your inverter in the garage. e.g. 3.68kW, 5kW
    * **Capacity DC (Panels kW):** e.g. 10 panels x 400W = 4kW. This is your array's maximum bragging rights.
    * **Azimuth:** Which way do your panels face?
        * 0 = North (Half a loaf is better than no bread)
        * 90 = East (Morning person)
        * 180 = South (Perfect! You're a star!)
        * 270 = West (Evening sun lover)
    * **Tilt:** How steep is your roof? Most Irish roofs are 30-40 degrees. Put 35 if you have no idea and want to wing it.
    * **Efficiency Factor:** Leave at 90%. That's for dust, bird poop, and general Irish weather.

Hit **Save**.

You get 2 free sites, so if you have panels East AND West, you can add both. Solcast are sound like that. New accounts get 10 API calls a day - don't go mad refreshing it.

===== STEP 4: How to See TOMORROW'S Forecast - The Future is Bright! =====

==== The Quick & Lazy Way: ====

    1. Log in and look at the big graph at the top.
    2. It shows 3 days in the past and 3 days in the future. Today has a dotted line.
    3. Tomorrow is to the right of that line. Hover over it. It'll show you the kW.
    4. Scroll down a bit and it tells you **Total kWh forecast for tomorrow**. That's your magic number.

If it says 20kWh tomorrow, that's your cue to NOT run the immersion tonight. Let the sun do the heavy lifting.

==== The Nerdy But Accurate Way: ====

    1. On the dashboard, find **‘Download data from the API’**.
    2. Make sure **‘Forecasts’** is orange/active. Not 'Live'.
    3. Select **‘CSV’**.
    4. Click **‘Download CSV’**.
    5. Open in Google Sheets / Excel.
    6. You'll see a column called **PvEstimate**. Find all the numbers for tomorrow, hit SUM (the Σ symbol), then **multiply by 0.5**.

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**Maths:** Sum x 0.5 = kWh for tomorrow. e.g. 40kW total = 20kWh.
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So you can plan ahead, simples.

If Solcast says tomorrow will be *shite*, charge tonight.
If Solcast says tomorrow will be *sun-tastic*, wait for free power from that big yellow thing in the sky.

You're now officially a solar forecaster. Your panels will be *current-ly* very happy with you.
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☕ **Solar Sid's Tip:** Once you know tomorrow's kWh, plug it into my [[https://solarsid.eu/Irish-solar-calculator.html|Irish Solar Calculator]] with your real usage file to see if you should hold off on the battery top-up.

**[[https://buymeacoffee.com/solarsid|☕ Buy Solar Sid a coffee to keep the site independent]]**
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