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Maintainers -ImageDr. Will Usher

Solver Configuration

At OET, we use both open source and proprietary solvers. Proprietary solvers require a license. Users must configure the details of the solver license before using them.

Configuring Gurobi​

Our gurobi license is limited to 15 users in parallel. If a project is running multiple solves in parallel, we can run out of available licenses. As OET expands, license contention will become an increasing problem, some coordination is happening on discord and Google Calendar.

There are multiple ways to configure Gurobi. Snakemake before version 9.14.6 acquired configured licenses whenever you started it, so please make sure to update it to at least >=9.14.6.

Standard Approach​

Rename and copy the gurobi.lic file in your /home/<you> folder. Get solving...

Discouraged Approach​

warning

This added the Gurobi license key as part of the config into created PyPSA network files. Therefore this approach is now discouraged, please move to the Standard Approach and remove the key from your configuration files.

We used to include the license key as part of the PyPSA configuration file by editing the config/config.yaml file (which is not tracked in version control) to include:

solving:
  solver_options:
    gurobi-default:
      env:
        WLSACCESSID: "..."
        WLSSECRET: "..."
        LICENSEID: ...

FAQ​

Q. What if I already have a gurobi.lic file in my home folder? Will the environment variable entries take precedence?

A. No, you must remove the Gurobi license file from your home folder.

Q. How do I prevent license secrets from being included in a Pull Request?

A. The config/config.yaml file is not tracked - it is ignored by git. This PR adds gitleaks to the pre-commit, and warns of any secrets about to be added to the git history.

Further reading​