Long Term Adequacy Metrics - February 2009

February 2, 2009

The following changes have occurred to the Long Term Adequacy Metrics since the last posting (Long Term Adequacy Metrics -November 2008):

Demand Forecast: 

The forecasted demand has been update to include the most recent AESO forecast, AESO’s Future Demand and Energy Outlook (2008-2028).  The new forecast is generally lower than the previous demand forecast.  The lower demand forecast has contributed to producing a more optimistic supply adequacy situation.  Details on the forecast can be found in the load forecasting section of the website.  http://www.aeso.ca/transmission/8638.html

New Generation Projects and Retirements Metric: 

  • Projects completed and removed from list:  
    • ATCO Valleyview 2 (47 MW)
  • Generation projects moved to “Active Construction”:  
    • EPCOR Clover Bar Peaker 3 (101 MW)
  • Generation projects moved to “Regulatory Approval”:     
    • Glacier Power Dunvegan (100 MW)
  • Generation projects that have been added to “Announced, Applied for AESO Interconnection, and/or Applied for Regulatory Approval":
    • University of Calgary Cogeneration Unit (15 MW)
    • Otoka Gasification (25 MW)
  • Generation projects that have been added to “Deferred”:
    • Petro-Canada/UTS Fort Hills Mine (130 MW)
    • Imperial Oil Kearl Cogeneration (255 MW)
    • Shell Carmon Creek (370 MW)
    • Suncor Firebag Stage 4 (160 MW)
    • Petro-Canada/UTS Fort Hills Upgrader (415 MW)

Changes to generation projects:   

  • Shell - Caroline MCR has changed to 19 MW from 20 MW
  • CNRL - Horizon Phase 1 MCR has changed to 103 MW from 101 MW
  • EPCOR - Clover Bar Peaker 2 ISD has changed to Apr-2009 from Nov-2008
  • Grande Prairie Generation -  Northern Prairie Power Project MCR has changed to 93 MW from 85 MW
  • ENMAX – Crossfield Energy Centre ISD has changed to Nov-2009 from 2009
  • Verdant Energy – Dapp Power Westlock Expansion ISD has changed to Sep-2009 from 2008
  • Suncor – Firebag Stage 3 ISD has changed to Aug-2009 from 2009
  • Project 788 MCR has changed to 63 MW from 113 MW
  • TransCanada – Saddlebrook Generation Station MCR has changed to 338 MW from 350 MW
  • TransAlta – Keephills 1 & 2 Uprates MCR has changed to 23 MW from 35 MW
  • Project 868 ISD has changed to Jul-2014 from Apr-2012
  • ENMAX – Shepard Energy Centre MCR has changed to 800 MW from 1000 MW

Reserve Margin Metric:

  • The 2007 and 2008 reserve margins have been updated to reflect actual AIL and AIES demand peaks in those years.  The forecasted reserve margin has been updated to include 2014.

Supply Cushion Metric:

  • The forecasted supply cushion has been updated to reflect the new time period.

Two Year Probability of Supply Adequacy Shortfall Metric:

  • New values for the metric have been calculated with Total Energy Not Served decreasing from 951 MWh to 145 MWh. This new value is below the 1600 MWh threshold.

1.  New Generation Projects and Retirements Metric:

The New Generation Projects and Retirements Metric is a summary of generation at various stages of development in Alberta and is shown in Tables 1 to 5 below. In Alberta’s deregulated electricity market competitive forces determine the location, magnitude and timing of new generation additions. Information on prospective generation additions and retirements provides context for the future market in Alberta.  The information is drawn from a variety of public sources and includes new generation, changes to existing generation and retirement of generating units. While the metric includes only new wind generation projects under construction, a list of all new wind projects is available in the AESO Generation Interconnection Queue.

 

Table 1: Generation Projects under Active Construction

 

Table 2: Generation Projects with Regulatory Approval

 

Table 3: Generation Projects that have been Announced, Applied for AESO Interconnection, and/or Applied for Regulatory Approval

 

Table 4: Generation Projects that have been Deferred

 

Table 5: Generation Projects that have Announced to Retire

 

2.  Reserve Margin Metric:

The Reserve Margin Metric, shown in Figure 1, presents a comparison of generation supply and demand in Alberta.  It is calculated by taking the amount of firm generation capacity at the time of system peak that is in excess of the system annual peak demand, expressed as a percentage of the system peak.  Firm generation is defined as installed and active construction generation capacity, adjusting for seasonal hydro capacity and behind the fence demand and generation and excludes wind capacity.  The forecasted reserve margin shows a decline from historically high margins.  The Reserve Margin Metric does not include the numerous projects that are approved or announced.  The reserve margin is graphed with and without intertie capacity since full import capability may not always be available at the time of system peak demand.

 

3. Supply Cushion Metric:

The Supply Cushion Metric provides visibility of the Alberta Interconnected Electric System’s ability to meet peak demand on a daily basis.  The supply cushion is the difference between the daily available firm supply minus daily peak demand.  The supply cushion refines the reserve margin calculation by using daily system peak rather than annual.  Figure 2 presents the estimated daily supply cushion for the next two years.  Figure 3 presents daily peak demand and firm supply by fuel type, as well as interties, wind and back up generation (Rainbow/Rossdale) which are not included in the supply cushion calculation due to the intermittent or uncertain nature of the supply.  When the supply cushion is negative in Figure 2, there is an increased level of reliance on interties, wind and back up generation, as indicated in Figure 3.

4.  Two Year Probability of Supply Adequacy Shortfall Metric:

The Two Year Probability of Supply Adequacy Shortfall Metric is a probabilistic assessment of encountering a supply shortfall over the next two years. It builds on the Supply Cushion Metric by incorporating the probability of wind production, forced generation outages and generation derates into the calculation of hourly firm supply. The calculation estimates, on a probabilistic basis, how much load may go without supply over the next two year period. Based on extensive consultation with stakeholders, when this unserved energy exceeds 1,600 MWh in any two year period (equivalent to one hour 800 MW shortfall in each of the two years), the AESO may take certain actions to bridge the temporary supply adequacy gap without impacting investor confidence in the market. The total energy not served shown in Table 6 does not reach the threshold.

 

Table 6: Two Year Probability of Supply Adequacy Shortfall