Global Adjustment and Peak Demand Factor

Class A customers are assessed their portion of GA costs based on the percentage that their consumption contributes to the top five system coincident peaks during a predetermined base period, referred to as their Peak Demand Factor.

For example, if a Class A customer is assessed to be responsible for one per cent of Ontario's coincident peak demand for the five highest hours of a set base period, they will be charged for one per cent of total GA costs through the next adjustment, or billing period.

For more detailed information, see the Industrial Conservation Initiative Backgrounder.

Base period

Class A customers are assessed their portion of GA costs based on the percentage that their consumption contributes to the top five system coincident peaks during a predetermined base period (May 1-April 30) and will be charged their percentage of total GA costs through the next adjustment, or billing period (July 1-June 30).

Base Period (Peak-setting Period)

Adjustment Period (Billing Period)

May 1, 2019 to April 30, 2020

July 1, 2020 to June 30, 2021

May 1, 2018 to April 30, 2019

July 1, 2019 to June 30, 2020

 May 1, 2017 to April 30, 2018

 July 1, 2018 to June 30, 2019

May 1, 2016 to April 30, 2017

July 1, 2017 to June 30, 2018

May 1, 2015 to April 30, 2016

July 1, 2016 to June 30, 2017

May 1, (Year X) to April 30, (Year X+1)

July 1, (Year X+1) to June 30, (Year X+2)


Top 5 Peaks: Hours & System-Wide Consumption

The table below shows the final peak hours and the corresponding adjusted demand for the past base period. Embedded generation is included, as it represents Ontario demand that was met through local generation.

 

Base Period: May 1, 2018 to April 30, 2019

Date  Hour Ending Allocated Quantity of Energy Withdrawn
(MWh)
Embedded
Generation (MWh) 
 Energy
Storage
Injections (MWh)
Total* (MWh) 
September 5, 2018  17  22,551.315  1,076.151  0.446  23,627.020
 July 5, 2018  15  22,415.022  1,418.704  0.008  23,833.718
 July 4, 2018  18  22,122.730  734.709  0.393 22,857.046
August 28, 2018  17 21,643.799  1,069.941 0.581 22,713.159
September 4, 2018  17 21,379.327  803.919  0.759  22,182.487

*The value in the Total (MWh) column is the number used to calculate a customer’s Peak Demand Factor.

For historical peaks, download the Top 5 Peaks: Hours & System-Wide Consumption.

Calculating your Peak Demand Factor

After the IESO establishes the final top five Ontario demand peaks using adjusted AQEW for a base period, the IESO and LDCs then look at each Class A customer's consumption during those five hours (coincident peaks) to calculate their corresponding portion of peak demand. This portion is called a peak demand factor and is used to determine a customer's allocation of costs for the adjustment or billing period.

Example Calculation

A customer’s consumption during the
top 5 demand peak hours (MWh)
           

  3.1

   4.4

   3.9

   4.1

    4.3

   19.8

÷

 
Sum of Top 5 System-wide Consumption Peaks (MWh)

115,213.430

 =        Peak Demand Factor

0.00017185


How Class A customers are charged GA

The Class A customer's Peak Demand Factor is used to calculate monthly GA charges during the adjustment or billing period. This is done by multiplying the monthly Ontario-wide total GA costs by the customer's Peak Demand Factor.

Example Calculation

System-wide GA costs for a given month 

$999.6 M

See Total GA costs ($M)

x

Your Peak Demand Factor from example above

0.00017185

=  

Your GA charge for the month

$171,781.26