> ## Documentation Index
> Fetch the complete documentation index at: https://docs.transitionzero.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Creating a Scenario

> How to create a project and configure a new scenario: geography, model type, timeline, and temporal resolution.

In Scenario Builder, your work is organised into **projects** and **scenarios**:

* A **project** is a container for related scenarios, for example all the scenarios exploring one research question or country
* A **scenario** explores a single possible future for the electricity system, based on your assumptions about demand, technology, and policy

## 1. Create a project

From your workspace, click **New Project**, give it a name, and create it. You can rename or delete a project later from the project page.

<Frame caption="Creating a project in Scenario Builder">
  <video src="https://mintcdn.com/transitionzero/osbeq9BX8h30WOhO/images/project_creation.mp4?fit=max&auto=format&n=osbeq9BX8h30WOhO&q=85&s=6247c02890b4f1588b3c343d5f49b217" controls muted playsInline aria-label="Walkthrough of creating a new project" className="w-full rounded-xl" data-path="images/project_creation.mp4" />
</Frame>

## 2. Create a scenario

Open your project and click **New Scenario**. The form has a few core fields plus a **Configuration** section that sets the shape of your model.

<Frame caption="Creating a scenario in Scenario Builder">
  <video src="https://mintcdn.com/transitionzero/osbeq9BX8h30WOhO/images/scenario_creation.mp4?fit=max&auto=format&n=osbeq9BX8h30WOhO&q=85&s=991b9b5a39b2c3376307376dc4bb3c2b" controls muted playsInline aria-label="Walkthrough of creating a new scenario" className="w-full rounded-xl" data-path="images/scenario_creation.mp4" />
</Frame>

### Name and research question

* **Name**: a unique name for the scenario (e.g. *Growth economy*)
* **Research question** *(optional)*: a short description of what the scenario explores (e.g. *A high-growth economy with increased energy demand*). This is also a useful starting point for [AMP](/platform/amp-ai-assistant).

### Geographies and spatial resolution

Choose the **geographies** your scenario covers, then a **spatial resolution** that controls how finely those geographies are divided into nodes:

| Resolution         | What it means                                                                                                                                             |
| :----------------- | :-------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **National**       | The whole country is modelled as a single node.                                                                                                           |
| **Regional**       | The country is split into multiple interconnected nodes (e.g. states, islands, or grid zones), so the model can represent electricity flows between them. |
| **Multi-national** | Multiple countries are modelled together, with cross-border interconnectors.                                                                              |

The available resolutions and node counts differ by country. See the [Country models](/countries/overview) section for what each model offers. For more on how spatial detail affects results, see [Model resolution](/methodology/model-resolution#spatial-resolution-geographical-detail).

### Model type

Choose the framework that fits your question:

| Model type             | Best for                                                           | Framework                                    |
| :--------------------- | :----------------------------------------------------------------- | :------------------------------------------- |
| **Capacity Expansion** | Multi-year, long-term investment planning at lower time resolution | [TZ-OSeMOSYS](/methodology/model-frameworks) |
| **Dispatch**           | A single year of operation at high time resolution                 | [PyPSA](/methodology/model-frameworks)       |

See [Model frameworks](/methodology/model-frameworks) for a fuller comparison and guidance on choosing, and on *soft-linking* a capacity expansion plan into a dispatch model.

### Timeline

Set the years your scenario covers:

* **Capacity Expansion** runs over a range: pick a **Start** and **End** year
* **Dispatch** models a single year only

### Temporal resolution

Temporal resolution sets how many **time slices** the model uses to represent variation within a year. Each scenario's time slices are the product of *parts of a year* × *parts of a day*:

| Resolution | Time slices | Detail                                  |
| :--------- | :---------- | :-------------------------------------- |
| **Low**    | 1           | A single annual average.                |
| **Medium** | 32          | 4 parts of a year × 8 parts of a day.   |
| **High**   | 8760        | Full hourly detail (used for Dispatch). |

Higher resolution captures more demand and renewable variability but takes longer to solve. See [Model resolution](/methodology/model-resolution#time-slices) for the trade-offs.

## 3. What happens next

Every scenario starts from a **calibrated base model** with sensible default inputs, so you can run it immediately to get a least-cost baseline. From there you can:

<Steps>
  <Step title="Customise the inputs">
    Adjust any of the model's [input data types](/platform/input-types) to reflect your assumptions. See [Editing Scenarios](/platform/editing-scenarios) for how.
  </Step>

  <Step title="Run the model">
    Click **Run** and follow the [run statuses](/platform/run-statuses) through building, solving, and results.
  </Step>

  <Step title="Explore and compare">
    View your results and compare scenarios side by side.
  </Step>
</Steps>

<Tip>
  Only **draft** scenarios can be edited. To change a scenario that has already been run, [duplicate it](/platform/editing-scenarios#duplicating-a-scenario) first.
</Tip>