See also: Types of Tree Branches, Editing the Tree
The tree, which appears in the Analysis View, the Results View, and the Notes View is a hierarchical outline used to organize and edit the main data structures in a LEAP analysis. In the Analysis View you can edit the tree structure (for example, by right-clicking with the mouse on a tree branch An item on the tree. Different types of branches are represented by different icons on the tree , or by using the Tree menu options), and you also click on the tree to select the data you want to view and edit. In the Results View, you again use the tree, but this time as a means of accessing the various results calculated for different branches of the tree (for example energy demand in a particular sector or electricity production in different power plants). You can also user-defined tags to filter the branches shown in the tree.
Data in the tree are organized under major categories, which normally appear as the top level of branches in the tree:
Key Assumptions: under which you create and organize independent variables used to "drive" the calculations in your Demand, Transformation and Resource analyses. Key Assumptions are not directly calculated in LEAP, but they are useful as intermediate variables that can be referenced in your modeling calculations.
Effects: under which you can create externality cost values for different pollutants as well as constraints that serve to limit emissions in scenarios that use LEAP's least-cost optimization calculations. Note that the full list of effects in an are accessed via the General: Effects screen. Effects from that complete list can selectively be added to the list of pollutants displayed under the Effects Tree branch.
Demand: under which you create the disaggregated structure of your energy demand analysis. For more information, see: Demand Analysis.
Transformation: under which you create the structure of your Transformation analysis. Transformation analyses simulate the conversion and transportation of energy forms from the point of extraction of primary resources and imported fuels all the way to the point of final fuel Something combusted, or otherwise used to produce energy consumption. As with your demand analyses, you can create alternative scenarios to represent different future Transformation configurations reflecting alternative assumptions about policies and technologies. Transformation data are defined at two main levels of detail. The module A Transformation branch representing an energy industry or sector, such as electricity generation, oil refining, district heating, charcoal production, or electricity transmission and distribution level represents energy industries or sectors such as electricity generation, refining, district heating, or charcoal production. Below each module, you describe the individual processes within a module such as particular electric power plants or oil refineries, and the output fuels produced by the module. At the module level, you define the Settings for simulating the operation of the energy industry, such as whether you wish to specify capacity restrictions, and how you want to simulate the dispatch of different processes. For each process A Transformation branch that describes an individual technology or group of technologies within a module such as a particular electric plant or oil refinery , you define technology data such as the input fuels to each process, capacities, efficiencies, capacity factors, capital and operating and maintenance costs, and emission factors. For more information, see: Transformation Analysis.
Resources: under which you create a data structure to reflect the production of indigenous resources and the import and export of secondary fuels. For more information, see Resource Analysis.
Non-Energy Sector Effects: under which you can create scenarios for Non-energy related effects. Typically you will use these branches for inventories and scenarios of non-energy sector greenhouse gas (GHG) emissions, as a complement to the analysis of energy sector greenhouse gas emissions and mitigation measures conducted in the other parts of LEAP. For more information, see Non-Energy Sector Effects Analysis.
Stock Changes and Statistical Differences: These two additional top level branch categories are visible only if you place a checkmark next to the option "Statistical Differences and Stock Changes", on the Default tab of the Settings screen.
Indicators. Indicators are used to calculate additional user-defined results.
When using the tree in the Results and Notes Views, an additional top level branch is displayed showing the name of the current Area The energy system being studied. Clicking on this branch lets you review results summed across both Demand and Transformation branches (for example, total emissions for the area). This branch does not appear in the Analysis View. Note also that some branches for which no results are available are hidden in the Results View. These include the "Key Assumptions" branch, and all branches below it, as well as Transformation Outputs branches.
In areas with more than one region you can use the Tree: Select Visible Branches option to selectively show or hide branches in different regions. Hidden branches are not included in a region's calculations.
In Results View, when showing results with tags or branches selected for the chart legend, LEAP will color code the tree using the same colors as used in the chart. This makes it easy to see how the results in the chart correspond to the branches in the tree (or the tags set at those branches). When branches are the selected dimension in the Chart legend, LEAP will automatically expand the tree to show you the colored tree branches corresponding with the items in the chart. This capability also works if you have more than one depth level selected. If you do not wish to have the tree color-coded you can switch off this capability from the View menu using the View: Color Tree Branches menu option.