Getting started (no coding needed)
This page is for trying G2ELin out without knowing Python. There are three steps, and nothing is installed outside the folder you download.
1. Install Python (once)
Download it from python.org/downloads and run the installer.
On Windows, tick “Add python.exe to PATH” on the first screen of the installer before clicking Install. That single checkbox is what lets everything else work.
On macOS, run the installer and then also double-click “Install Certificates.command” in the Python folder that Finder opens.
2. Download G2ELin
On the repository page on GitHub: the green Code button → Download ZIP. Then unzip it — on Windows, right-click the file → Extract All — somewhere like your Documents folder.
(If you use Git, git clone the repository instead; it is the same thing.)
3. Start it
Open the folder you just unzipped and:
Windows — double-click
start-windows.bat. Windows may show a blue “Windows protected your PC” box the first time, because the file was downloaded: click More info → Run anyway.macOS / Linux — open the Terminal in that folder and run
./start-macos-linux.sh.
A black window opens and prints what it is doing. The first time it takes a few minutes: it is downloading the scientific libraries it needs and building the manual. When it is ready your browser opens on the tool.
If the browser does not open by itself, go to http://127.0.0.1:8000.
While it is running
Keep that black window open — it is the program. To stop, close it or
press Ctrl+C in it. To use G2ELin again later, double-click the same file:
from then on it starts in seconds.
Where to go first
The Home page introduces the tool and lists the preset networks. A good first pass:
Network — pick a preset, for example CIGRE MV interconnected. The diagram is drawn straight away; click any element to see and edit its parameters.
Power Flow — press Run power flow. The network is coloured by the results, and hovering an element shows its own.
Modal Analysis → Eigenvalue map — the same network, linearised: every mode with its frequency and damping.
Time-Domain Simulation — pick a disturbance and press Run. This is the slow one: a large network takes a few minutes.
If a run is too slow. By default every element is modelled in full detail, which is what makes a run an EMT simulation — and what makes it slow, because the fast dynamics force the solver into very small steps. The Model order panel on the Network page lets you drop them: set the network to Quasi-stationary and the machines to 6th order and the same case becomes an electromechanical (RMS) study, which is what a stability tool would run and is far quicker. The panel’s Check this model against the full one button then tells you whether that reduction is safe for your particular network, instead of leaving you to guess.
Keeping your work. On the Network page, My networks saves whatever you
have built or modified under a name and brings it back next time, even after
closing the browser; unsaved edits are kept too and offered back on your next
visit. Saved networks live in your browser, so open the tool at the same
address each time (http://127.0.0.1:8000), and press Export all (backup)
now and then: that file can be re-imported here or on another computer.
There is also a narrated video tour of the whole interface in the
repository’s Documentation/ folder.
If it does not start
“python is not recognised” — Python is installed but not on the PATH. Run its installer again, choose Modify, and tick “Add python.exe to PATH”.
The window flashes and disappears — start it from a terminal instead so the message stays on screen: open the folder in Windows Explorer, type
cmdin the address bar, press Enter, then typestart-windows.bat.“address already in use” — G2ELin is already running in another window; use that one, or close it and start again.
Anything else — send the last ten lines of that black window; they say what failed.
Installation and setup has the same steps as plain commands, plus the test suite, the notebooks and the server deployment.