1. Transmission Planning in a Dynamic Environment
Goodwin & Juricek – Oncor Electric Delivery
Aivaliotis, Mohr & Stelmak - The Valley Group
2015 Grid of the Future Symposium

2. Planning Environment Has Changed

3. Planning Environment is now dynamic
Vertical Utility
Current & Future World
Controlled Service Area
Segment of ISO
New Generation Met Demand
New Generation is a Potpourri
Generation Siting Known by Planning
No Control on Generation Location
Lead Times Managed by Planning
Lead Times Manage Planning
Lead Times in Years
Lead Times Much Shorter
Load & Generation Stayed
Existing Load & Generation Turn to Vapor
Staged Response
Dynamic Response
Planning Environment is now dynamic

4. Dynamic Line Rating in the Planner’s toolbox
Enhancing Planning & Operations by providing safety and reliability through added capacity and WASA
Preparing a more efficient cost effective least-regrets capital strategy
Providing a bridge to accelerate and facilitate transmission builds
Resolving present and future line derating issues
Addressing the next limiting element
Dynamic Line Rating in the Planner’s toolbox

5. Planning Cycle generates lists
Scenarios
N-1 Scenarios are Studied
1,000s of
Project Lists
Prioritized Lists of Project Solutions Ranked by Need
Capital Budget Approval
Priority Projects that meet cost/benefit criteria get approved; rest wait their turn
Planning Cycle generates lists

6. Planning Cycle generates lists
Scenarios
1,000s of
N-1 Scenarios are Studied
Project Lists
Prioritized Lists of Project Solutions Ranked by Need
Capital Budget Approval
Priority Projects that meet cost/benefit criteria get approved; rest wait their turn
Many Projects do not make the cut for capital funding either for limited budget reasons or inadequate benefit/cost ratio.
Project needs vary from1% overload to 10s% of overload.
What if you could expand your effective budget and address more of these issues!?
Planning Cycle generates lists

7. Dynamic line rating provides capacity
Static Ratings – conservative worst case conditions
Ambient Temperature Ratings – ambient temperature
Dynamic Ratings – temperature & wind
Capacity
Dynamic line rating provides capacity

8. Dynamic line rating provides capacity

9. Dynamic line rating provides capacity
Cumulative Probability Rating Curve
Slide depicts that each line will have a different DLR due to terrain, orientation, and other line characteristics.
One size does not fit all.
Dynamic line rating provides capacity

10. How Much DLR Capacity do I need?
Peak Day
Annual Trend
% Capacity Increase by DLR
% Congestion-cost Reduction
+5%
59%
34%
+10%
77%
45%
Based on DLR modeled on several lines that had congestion
No shift of congestion to adjacent “peripheral” lines
ISOs operate their grid to optimize overall cost
How Much DLR Capacity do I need?

11. Dynamic line rating provides capacity
Cumulative Probability Rating Curve
+5% Available 96% of the time
+10% Available 92% of the time
Dynamic line rating provides capacity

12. Dynamic line rating provides capacity key takeaways
Each line has its unique exposure & ratings
5-10% Increase in Capacity is ALL you need
This capacity is available 92-96% of the time
Dynamic line rating provides capacity key takeaways

13. Least-Regrets Capital strategy
Our Grids are DYNAMIC
New and Lost Generation
Locations of Load & Generation Out of Our Control
Lead Times are Short
Leads to Constantly Changing
Grid Topology
Power Flows
System Dynamics
Projects in Queue Appear and Disappear; Grow and Ebb
Least-Regrets Capital strategy

14. Least-Regrets Capital strategy

15. Least-Regrets Capital strategy
Why Least-Regrets?
Capital investments could have reduced value to the grid in the future
Grid topology changes and a path or several paths that were critically overloaded are now woefully under-utilized
DLR can be a fast, short-or long term less costly alternative solution to a large capital investment solution
Least-Regrets Capital strategy

16. DLR – Bridge to the future
Short-lead Times
Project Need that Rises and Ebbs – Stays Small but Needy
DLR can be a solution that
Meets the Need
Has a Short Lead Time months
Is very cost effective per MW of capacity
Defer Larger Capital Investments
DLR – Bridge to the future

17. Derated Line Solutions
Many utilities faced the need to derate lines following the course of the NERC Alert process; i.e. the line as built did not have the clearances expected when designed.
DLR can restore as much capacity as the line has to give by monitoring the line characteristics in real-time and streaming that data to the operating center.
The line is still governed by the conditions identified in the NERC Alert assessment, but only dictate operations when encountered.
ONE NOTE – Monitor the entire line length – Wind is Shifty and it Doesn’t Blow the same along the entire line at the same time. Think WASA
Derated Line Solutions

18. Derated Line Solutions

19. DLR - Cost Effective Alternative
Line Type
Alternative Description
New Rating
(% of Static)
Work Required
M&L Cost Per Mile
138 kV Lattice & Wood H-frame
Reconductor ACCC
193%
Reconductor
$ ,851
DLR
110%
$ ,200
138 kV Wood H-frame
Rerate 125 °C
Modify Strs
130%
Modify 6 H-frames
$ ,561
Replace Strs
Replace 6 H-frames
$ ,919
Rebuild
209%
Rebuild Line
$ ,000
$ ,471
140%
$ ,871
$ ,767
212%
$ 750,000
$ ,323
345 kV Lattice Tower
Raise structure heights
120%
Raise Str Heights
$ ,600
$ ,626
DLR - Cost Effective Alternative
Assume project needed 10% added capacity

20. summary Transmission Grids Have a Dynamic Topology
Transmission Planning Must Have Many Alternative Solutions
Cost
Lead Time
Proportionate Capacity Enhancements
Dynamic Line Rating Provides
5-10% Additional Capacity >95% of the Time
Using DLR Streamed to Operations Provides Grid Flexibility to Mitigate Constraints
Provides Short Lead-time Solutions
Extends Capital Budget with More Cost Efficient Solutions
Increases Safety and Reliability with Added Capacity
summary