Our electricity distribution system has technical limits to the amount of generation that can be connected at any point on the network. When the technical limits are reached, the system is considered to have reached its capacity. The capacity for various sections of the distribution system varies as it is dependent upon the equipment installed along the path from the generator to the user.


Download our Station and Feeder Capacity Calculator (Microsoft Excel or LibreOffice required).

In order to accept electricity generated by a generation project, Hydro One must ensure there is sufficient capacity available to deliver the electricity to those who need it. This can only be accurately determined by performing a Connection Impact Assessment (CIA), which is done when the generator submits a Form B to Hydro One.

To help generators make preliminary decisions regarding their projects, we publish information regarding the estimated capacity available at our transformer stations. We have replaced the List of Allocated Capacity with the List of Station Capacity and List of Applications to help generators collect potential capacity information.


List of Station​ Capacity – This list shows an approximate amount of generation that can be added at each bus or station owned by us.  Note that the list shows approximate values only and the actual capacity can only be determined by completing a Connection Impact Assessment (CIA).


List of Applications ​–​ This list shows the applications to connect to our distribution system, as of this update.

We are committed to connecting renewable sources of power to our electricity grid. Watch this video, Connecting Renewable Generation, to learn about our progress and about some of the technical issues we are working to overcome.


Connecting Renewable Generation