Analysing a model

Calliope inputs and results are designed for easy handling. Whatever software you prefer to use for data processing, either the NetCDF or CSV output options should provide a path to importing your Calliope results. If you prefer to not worry about writing your own scripts, then we have that covered too! The built-in plotting functions in plot are built on Plotly’s interactive visualisation tools to bring your data to life.

Accessing model data and results

A model which solved successfully has two primary Datasets with data of interest:

  • model.inputs: contains all input data, such as renewable resource capacity factors
  • model.results: contains all results data, such as dispatch decisions and installed capacities

In both of these, variables are indexed over concatenated sets of locations and technologies, over a dimension we call loc_techs. For example, if a technology called boiler only exists in location X1 and not in locations X2 or X3, then it will have a single entry in the loc_techs dimension called X1::boiler. For parameters which also consider different energy carriers, we use a loc_tech_carrier dimension, such that we would have, in the case of the prior boiler example, X1::boiler::heat.

This concatenated set formulation is memory-efficient but cumbersome to deal with, so the model.get_formatted_array(name_of_variable) function can be used to retrieve a DataArray indexed over separate dimensions (any of techs, locs, carriers, costs, timesteps, depending on the desired variable).

Note

On saving to CSV (see the command-line interface documentation), all variables are saved to a single file each, which are always indexed over all dimensions rather than just the concatenated dimensions.

Visualising results

In an interactive Python session, there are four primary visualisation functions: capacity, timeseries, transmission, and summary. To gain access to result visualisation without the need to interact with Python, the summary plot can also be accessed from the command line interface (see below).

Refer to the API documentation for the analysis module for an overview of available analysis functionality.

Refer to the tutorials for some basic analysis techniques.

Plotting time series

The following example shows a timeseries plot of the built-in urban scale example model:

In Python, we get this function by calling model.plot.timeseries(). It includes all relevant timeseries information, from both inputs and results. We can force it to only have particular results in the dropdown menu:

# Only inputs or only results
model.plot.timeseries(array='inputs')
model.plot.timeseries(array='results')

# Only consumed resource
model.plot.timeseries(array='resource_con')

# Only consumed resource and `power` carrier flow
model.plot.timeseries(array=['power', `resource_con`])

The data used to build the plots can also be subset and ordered by using the subset argument. This uses xarray’s ‘loc’ indexing functionality to access subsets of data:

# Only show region1 data (rather than the default, which is a sum of all locations)
model.plot.timeseries(subset={'locs': ['region1']})

# Only show a subset of technologies
model.plot.timeseries(subset={'techs': ['ccgt', 'csp']})

# Assuming our model has three techs, 'ccgt', 'csp', and 'battery',
# specifying `subset` lets us order them in the stacked barchart
model.plot.timeseries(subset={'techs': ['ccgt', 'battery', 'csp']})

When aggregating model timesteps with clustering methods, the timeseries plots are adjusted accordingly (example from the built-in time_clustering example model):

Plotting capacities

The following example shows a capacity plot of the built-in urban scale example model:

Functionality is similar to timeseries, this time called by model.plot.capacity(). Here we show capacity limits set at input and chosen capacities at output. Choosing dropdowns and subsetting works in the same way as for timeseries plots

Plotting transmission

The following example shows a transmission plot of the built-in urban scale example model:

By calling model.plot.transmission() you will see installed links, their capacities (on hover), and the locations of the nodes. This functionality only works if you have physically pinpointed your locations using the coordinates key for your location.

The above plot uses Mapbox to overlay our transmission plot on Openstreetmap. By creating an account at Mapbox and acquiring a Mapbox access token, you can also create similar visualisations by giving the token to the plotting function: model.plot.transmission(mapbox_access_token='your token here').

Without the token, the plot will fall back on simple country-level outlines. In this urban scale example, the background is thus just grey (zoom out to see the UK!):

Note

If the coordinates were in x and y, not lat and lon, the transmission trace would be given on a cartesian plot.

Summary plots

If you want all the data in one place, you can run model.plot.summary(out_file='path/to/file.html'), which will build a HTML file of all the interactive plots (maintaining the interactivity) and save it to out_file. This HTML file can be opened in a web browser to show all the plots. This funcionality is made avaiable in the command line interface by using the command --save_plots=filename.html when running the model.

See an example of such a HTML plot here.

Saving publication-quality SVG figures

On calling any of the three primary plotting functions, you can also set save_svg=True for a high quality vector graphic to be saved. This file can be prepared for publication in programs like Inkscape.

Note

For similar results in the command line interface, you’ll currently need to save your model to netcdf (--save_netcdf={filename.nc}) then load it into a Calliope Model object in Python. Once there, you can use the above functions to get your SVGs.

Reading solutions

Calliope provides functionality to read a previously-saved model from a single NetCDF file:

solved_model = calliope.read_netcdf('my_saved_model.nc')

In the above example, the model’s input data will be available under solved_model.inputs, while the results (if the model had previously been solved) are available under solved_model.results.

Both of these are xarray.Datasets and can be further processed with Python.

See also

The xarray documentation should be consulted for further information on dealing with Datasets. Calliope’s NetCDF files follow the CF conventions and can easily be processed with any other tool that can deal with NetCDF.

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