With large industrial companies adding new technologies and sensitive electronic equipment to their operations, PQ issues have become more important than ever. We respond to our customers’ needs with a Power Quality Inquiry Reporting Process.


ince the transmission system is interconnected, in some cases one customer’s equipment can adversely affect the quality of electrical supply to another customer. For example, large motors, arc furnaces, a large number of non-linear loads such as variable speed drives, or power factor correction capacitors can all contribute to power quality disturbances. It is also possible that normal switching on our network equipment may adversely affect our customers. These are only two examples of the types of power quality disturbances that our customers may experience. 

If you are an LDC, a Distribution-connected or Transmission-connected customer and would like to report a PQ incident, please complete our online form or contact the Hydro One Commercial & Industrial Customer Relations Team via email at CICR@HydroOne.com or by phone at 1-866-922-2466.

Report a Power Quality Incident  


Improving Our Power Quality Service to You

If you are a customer with a facility connected to our electrical system, we understand that PQ and reliability are very important to you. As a company, we want to better understand your electricity needs and improve your overall customer experience. In response to the feedback from a number of our customers, we have created PQ materials (see links below), which contain detailed information about our PQ Customer Satisfaction Improvement Project (PQ-CSI) - an initiative to help meet and hopefully exceed your PQ and reliability needs.

We understand that timing is everything when it comes to your business. The PQ-CSI project was designed to measure the reliability of our supply to you in more detail and resolve issues as quickly as possible. This project is leading the company towards improved PQ intelligence, enhanced PQ processes, new solution identification procedures and proactive customer service.
One of the main objectives of the PQ-CSI Project is to establish governance and strengthen the roles and accountabilities of our staff when it comes to PQ issues. This ensures we get the job done and we get it done right. PQ issues influence a wide range of staff and require a coordinated effort to resolve. Accountabilities and decision making are important and that is why we have strengthened our measures at all staff levels and across every Line of Business.

We hope you find the below information valuable, and as always, we want your feedback. Any comments or questions you may have about this information can be directed to your Account Executive or LargeAccounts@HydroOne.com.


PQ Reference Materials:


Power Quality — What It Means to Us

Power Quality refers to characteristics of electricity at a given point on the delivery path, as it relates to the compatibility between the electricity supplied on a network and the loads connected to that network. In short, everything in between “power is off" and “power is on" relates to PQ. Reliability differs from PQ. It refers to a loss of power at the delivery point only (see diagram below).


Image of Power Quality Domain and Everything in Between



In more technical terms, a PQ disturbance is associated with the deviations in the magnitude and frequency of the sinusoidal waveform. A deviation in the sinusoidal waveform may occur when power remains on and a transmission interruption does not occur (e.g. the lights stay on, but it may flicker or dim). It can take many forms, such as: voltage sag, phase unbalance and voltage swells, transient disturbances, momentary interruptions, and long-term steady state waveform distortions. For a more detailed look at specific power quality disturbances, read our Power Quality Definitions page.


Potential Problems — Minimize the Risk by Design

Customers should contact us for advice before upgrading major systems, adding substantial equipment, or changing hours of operation so that we can help you design your facilities to work efficiently with our transmission system, thereby minimizing the risk of PQ disturbances and avoiding any adverse impact on your facilities, as well as ours.

PQ issues may arise from one or a combination of events on the transmission system, a utilities’ distribution system, or a customer’s own plant system and equipment. Joint co-operation between various stakeholders and our teams is important to address PQ incidents.