Capacity Performance – Ramp Rate
Rebecca Stadelmeyer
Sr. Consultant, Market
Operating Committee
February 9, 2016
www.pjm.com
PJM©2015
Unit Parameter/ Values – Stakeholder Venues
www.pjm.com
2
PJM©2015
Ramp Rate Inclusion Option Paths
Ramp
Excluded
Ramp Rate Option Path
Ramp
PLS
Problem Statement
Potential Long Term
Excused MW:
• Approved Planned /
Maintenance Outage
• Not Scheduled by PJM
• Scheduled Down by PJM
Excused MW:
• Approved Planned /
Maintenance Outage
• Not Scheduled by PJM
• Scheduled Down by PJM
• Following PJM Dispatch
that includes ramp rate
Excused MW:
• Approved Planned /
Maintenance Outage
• Not Scheduled by PJM
• Scheduled Down by PJM
• Following PJM Dispatch
that includes ramp rate
Non-Performance Charge
calculated from ‘desired’ nonramp limited basepoint
Non-Performance Charge
calculated from ramp limited
basepoint
Non-Performance Charge
calculated from ramp limited
basepoint
Status Quo
(CP Order)
www.pjm.com
3
PJM©2015
Example without Proposed Ramp Rate Hour Assessment
Emergency Action Issued at 1900
Procedure Effective 1900 - 2000
Performance Assessment Hour is 1900
CP Commitment MW = 60 MW
Resource = Generator
Ramp Rate = 0.5 MW/min
Balancing Ratio = 0.80
Expected Performance = CP Commitment MW * Balancing Ratio
Scheduled MW at 1900 = set to 60 MW (desired LMP basepoint)
Actual Output for HE 20 = 45 MWh (unit performs to ramp rate)
Expected Performance for HE 20 = 48 MWh
Shortfall for HE 20 = 3 MWh (48 Expected – 45 Actual)
Scheduled MW = 30MW  60 MW
Actual Output = 30 MW  60 MW using a 0.5 MW / min rate
Expected Performance = 48 MWh
Emergency Action Effective
Assessment Hour = 1
1915
1900
www.pjm.com
1930
4
1945
2000
PJM©2015
Example with Proposed Ramp Rate Hour Assessment
Emergency Action Issued at 1900
Procedure Effective 1900 - 2000
Performance Assessment Hour is 1900
CP Commitment MW = 60 MW
Resource = Generator
Ramp Rate = 0.5 MW/min
Balancing Ratio = 0.80
Expected Performance = CP Commitment MW * Balancing Ratio
Scheduled MW at 1900 = start at 30 MW and uniformly ramp to 60 MW (45 MWh integrated)
Actual Output for HE 20 = 45 MWh (unit performs to ramp rate)
Expected Performance for HE 20 = 48 MWh
Shortfall for HE 20 = 0 MWh (48 Expected – 45 Actual – 3 excused*)
*3 MW excused because ramp rate considered in the PAH Assessment
Scheduled MW = 30 MW  60 MW
Actual Output = 30 MW  60 MW using a 0.5 MW / min rate
Expected Performance = 48 MWh
Emergency Action Effective
Assessment Hour = 1
1915
1900
www.pjm.com
1930
5
1945
2000
PJM©2015
PAH Ramp Proposal
Initial Proposal
New Proposal
Compare daily inputted ramp rate to
a historical average ramp rate & use
the faster of the two during a PAH
Members review and update Ramp
rate in Markets Gateway by April 1,
2016
Benefits
Challenges
•
•
•
•
•
•
Technical implementation longer than
originally assessed
Input historical data quality a concern
Agreement on solution by June 1
www.pjm.com
6
Better values in the system for Dispatch
Can be implemented by June 1
Can be a transition step until better
solution developed, based on how
solution is working
PJM©2015
Historical vs Bid-In Ramp Rate Evaluation Examples
In order to perform a meaningful assessment of unit historical ramp rate performance against bid-in ramp rate, the
following sample data selection criteria were applied for the units evaluated.
•
Sample Hour Selection Criteria
• Occurred between December 1, 2015 and February 2, 2016
• No hours with Regulation or Spin Assignments included
• No hours with partial or full outages impacting unit output/performance
• Only hours where unit was Dispatchable (Eco Min ≠ Eco Max, with Dispatchable on-reason) and operating
in Dispatchable range (Eco Min < Unit Output < Eco Max) considered
•
Sample Minute Selection Criteria (for each of the above sample hours)
• Economic Base Point (Eco BP) indicating unit raise occurred within the last 5 minutes
• Unit Raise required by Base Point ≥ Bid-in ramp rate. For example, if a unit has a ramp rate of 10
MW/min, minute sample selected if within the last 5 minutes the Eco BP increased by at least 10 MW)
• Unit MW output remained the same or increased from the last minute
www.pjm.com
7
PJM©2015
Actual Unit Example: Combined Cycle Unit A
Unit A Bid-in Ramp Rate = 10 MW/min
Histogram of Actual Operating Values
www.pjm.com
8
•
Green Bars show % Frequency (left Y axis values) that unit
A responded for each positive MW Ramp (X axis values)
•
Light Blue Bar identifies the Bid-in Ramp rate of 10 MW/min
•
Dark Blue Line represents Cumulative % Frequency (right Y
axis values) for each MW Ramp. The Bid-in Ramp rate
(Light Blue Bar) intersects this line at ~92% indicating that
the unit A ramps in response to a valid (≥+10 MW) Eco BP
signal at less than 10 MW/min about 92 % of the time for
the sampled data.
•
From this data, it can be inferred that unit A rarely exceeds
its bid-in ramp rate of 10 MW/min.
•
Unit A normally ramps below its bid-in ramp rate, but is
capable of ramping at or slightly above (10 – 13 MW/min)
its bid-in ramp rate in response to a PJM dispatch signal.
PJM©2015
Actual Unit Example: Super Critical Steam Unit B
Unit B Bid-in Ramp Rate = 8 MW/min
Histogram of Actual Operating Values
www.pjm.com
9
•
Light Blue Bar identifies the Bid-in Ramp rate of 8 MW/min
•
Dark Blue Line represents Cumulative % Frequency (right Y
axis values) for each MW Ramp. The Bid-in Ramp rate
(Light Blue Bar) intersects this line at ~73% indicating that
the unit B ramps in response to a valid (≥ +8 MW) Eco BP
signal at less than 8 MW/min about 73% of the time for the
sampled data.
•
From this data, it can be inferred that unit B has ramped up
at a rate greater than its bid-in ramp rate of 8 MW/min a
significant number of times. It appears that unit B has a
conservative bid-in ramp rate based on actual performance.
•
Unit B ramps up normally below its bid-in ramp rate, but
appears to be capable of ramping at above its bid-in ramp
rate (in the 10 – 14 MW/min range) in response to a PJM
dispatch signal.
PJM©2015
New Proposed PAH Ramp Rate
Details
• Members to provide updated values into eMKT / Market Gateway by 4/1/16
• PJM / IMM review submitted ramp with member and compare to actuals observed
• Expectation is ramp rate NOT to change during a Hot Weather / Cold Weather Alert
• PJM will run a daily report to see if ramp rates changed during HW / CW alert
• If changed, PJM will require documentation to explain the reason for change
• If PJM does not agree with the explanation:
• PJM will assess Non-Performance Charge based on ‘desired’ basepoint
• Ramp rate will be an allowable excused MW when:
• Unit is at or above its economic minimum
• PJM has not issued a Manual Load Dump Action
• Manual Load Dump Action considered a ‘no notice’ event - generation ramp rate nor
DR notification time will be considered excuses for PAH Assessment
• Tariff change required to allow ramp included in the PAH Assessment
www.pjm.com
10
PJM©2015
Potential Long Term Solutions
Historical Comparison
PLS Value
Others?
Compare daily inputted ramp
Create a PLS value for ramp
rate to a historical average ramp
rate and treat it like all other
rate & use the faster of the two
PLS / Unit specific parameters
during a PAH
Tariff changes
Tariff and OA changes
Long Term Solution discussions should start as soon as transition plan is filed at FERC
www.pjm.com
11
PJM©2015
Next Steps
• Stakeholder consensus
• Stakeholder Voting and FERC filing
• First Read at February MRC and MC
• First Read and/or Vote at March OC
• Is an additional OC needed before March 8?
• Vote at March MRC and MC
• File at FERC by March 31 with effective date of May 31
www.pjm.com
12
PJM©2015