Transcript National Grid Local Area Load Serving Projects

National Grid
Local System Plan
Needs Assessment/Potential Solutions
PAC Meeting
September 30, 2009
Agenda
 Local System Plan (LSP) Background
 Purpose
 National Grid information
 Planning process
 LSP Project List
 Study Example
2
Purpose of Local System Plan
Per Attachment K – Local, the LSP is a report that:
 Describes projected improvements to non-PTF that are needed to
maintain system reliability
 Reflects:
 LSP Needs Assessments
 Corresponding transmission system planning and expansion studies
 Identifies:
 Local Planning Process
 Criteria, Data, and Assumptions
3
LSP Communication
 PAC, Transmission Customers, and other
Stakeholders have 30 days to provide any written
comments for consideration by National Grid.
 National Grid’s contact:
Gabriel Gabremicael
Mgr Transmission Planning, New England
National Grid
40 Sylvan Road
Waltham, MA 02451-1120
4
LSP Communication
Continued
 The ISO-NE RSP project list links to each individual
TO’s LSP project list.
 National Grid’s project list is located at:
 http://www.nationalgridus.com/oasis/filings_studies.asp
– "LSP - LTP Transmission Projects - August 2009"
5
Approach to Updates
 An LSP project list is required to be updated at
least annually.
 National Grid intends to update the posted
project list on a semi-annual basis to reflect
changes on projects.
 A presentation of the LSP will be made annually.
6
LSP Project List
 The LSP Project List is a cumulative listing of proposed
regulated transmission solutions that may meet LSP needs.
 Lower voltage facilities contained in the LSP Project List
pertain to facilities supplying our wholesale municipal
customers.
 The LSP Project List contains the status of each project:





7
Concept
Proposed
Planned
Under Construction
In Service
LSP Project List
Project Status Descriptions
(may vary slightly form RSP definitions)
Concept
Project is under consideration as possible solution to a need,
but little or no analysis is available
Proposed
National Grid has internally determined that the project is an
appropriate solution to a need, but has not yet obtained
Proposed Plan Approval (PPA) from ISO-NE (1.3.9 ISO-NE
approval)
Planned
Under
PPA has been approved (if required) and has internal approval.
Project has PPA approval and has internal approval.
Construction
In Service
8
Project is complete
Local System Planning Process
 Local studies can result from:
 Load Growth
 Area Reliability Assessments
 Point of Delivery Request from Customer
 Generation Interconnection Request
 A Planner –
 summarizes the results from the needs assessment and provides:
criteria, data and assumptions used in study
 builds study cases with proposed alternatives
 determines the most effective solution
 summarizes the results of the solutions study
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Criteria
 All National Grid facilities that are part of the
interconnected National Grid system shall be
designed in accordance with the National Grid
Transmission Planning Guide.
 The National Grid Transmission Planning Guide is
posted on our website under:
 http://www.nationalgridus.com/transmission/c38_standocs.asp
 as:
– Transmission Planning Guide
10
Data and Assumptions
Resources for studies:
 NEPOOL Library cases for load flow and ASPEN short
circuit studies
 CELT Report Load forecasts for NE wide loads
 Customer provided forecasted loads for local areas
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2009 LSP Projects
LSP – Massachusetts
Primary
Driver
Projected InService
Month/Year
Major
Project
Project
Current
Status
Needs Assessment
Solutions
Massachusetts
Load Growth
2010
Everett#37 Transformer Replacement
Concept
Two 115/13.8 kV transformers need
replacement due to contingency
overloading. Loss of 1 transformer
overloads the other past the
summer emergency rating and
could lead to extended outage.
Load Growth
2012
Mid Weymouth sub Add T1 40 MVA
Concept
Accommodate load growth in area.
Load Growth
2012
Read St Sub Replace T4 with 40 MVA
Concept
Loss of T5 transformer at Read St
Substation results in 354 MWHR
outage.
Load Growth
2013
Chartley Sub Replace T1 with 55
MVA
Concept
Accommodate load growth in area.
Load Growth
& Area
Reliability
Assessment
06/2011
Load Growth
9/2012
Area Reliability
Assessment
2015
Norwell Area C3 & S9 Line
Greater
L-164 Line Reconductoring
Boston Study
Marlboro Area
Study
Area Reliability
Assessment
13
2015
Concept
Proposed
New 115 kV line (OH or UG) from
Sudbury (NSTAR) sub to Hudson
(Municipal) sub. or
Concept
Convert W23W line 69 kV to 115 kV
from Northboro Rd sub to Marlboro sub
& upgrades substations
Concept
Upgrade the 115/13.8 kV transformers
from 40 MVA to 55 MVA & replace 5
airbreaks on high-side of
transformers with circuit switchers.
Replace Read St T4 transformer with
40 MVA, 115/ 13.2 kV non-LTC with
new foundation and replace cables to
modular bus with 2-2000 Cu/phase.
Rearrange station configuration to
serve 9L1-3 from T4 & 9L4-6 from T5.
.
Alternative 1: Build transmission line
interconnecting C3 & S9 with nearby
line; Alternative 2: CBs should be
Thermal overloads on C3 & S9 115
placed at Water St or Phillips Ln.
kV lines. Need to reconductor and
Water St has space constraints. Insectionalize with in-line circuit
line CBs at Phillips Ln; Alternative 3:
breakers.
Ring bus at Phillips Ln; Alternative 4:
Both breakers at Phillips Ln & Switch
closed permanently at Norwell sub
Due to local load growth need in
area line will overload at loss of
companion Y-151 line.
Reconductor with larger size.
Due to Load growth need in area, low
Considering New 115 kV line (OH or
voltage issues at Northboro Rd
UG) from Sudbury (NSTAR) sub to
substation, & overloading on W23W
Hudson (Municipal) sub.
(69 kV) line & E-157 (115 kV) line.
Due to Load growth in the area, low Part of potential solution is to convert
voltage issues at Northboro Rd
W23W and G7 (69 kV lines) to 115 kV
substation, & overloading on W23W from Northboro Rd sub to Marlboro sub
(69kV) line & E-157 (115 kV) line.
and South Marlboro sub
LSP – Massachusetts Continued
Primary
Driver
Area Reliability
Assessment
2014
Load Growth
2014
Load Growth
Load Growth
Load Growth
14
Projected InService
Month/Year
06/2013
TBD
2013
Major
Project
Project
Current
Status
Sandy Pond substation remove
distribution load from tertiary
Concept
windings of transformer and install
115-23 kV substation.
Tewksbury Substation - two new
Concept
115-13 kV #2 transformers.
Meadowbrook Substation - two
new 115-13 kV transformers.
Solutions
Reliability concern of serving 23 kV
Install new 115 kV source to supply 23
off of 345-115-13 kV transformer
kV load.
tertiary.
10 feeders exceeds summer normal
ratings by 2012 in the town of Lowell
and Chelmsford, MA & loading on 11 Proposal of two new 115/13.2 kV,
Concept
transformers will exceed summer 33/44/55 MVA, LTC transformers.
emergency ratings under a
contingency within the next 4 yrs.
Ayer substation relieve distribution
load from tertiary windings of
transformer and propose to install
Concept
two 115/23 kV transformers at
Devens proposed 115 kV
substation.
Union Loop Study
Needs Assessment
Move 13 kV feeders from Ayer 201
Station and off 115/69/13 kV
transformers to relieve contingency
loading issue for loss of single
transformer.
Alternative 1: Install two 115-13 kV 40
MVA transformers off proposed
Devens 115 kV station and move 13
kV feeders from Ayer 201 Station.
Alternative 2: Reconfigure 115 kV at
Ayer substation to accommodate two
115-13 kV transformers.
Develop a 115 - 13.8 kV supply point
in the Foxborough/ Wrentham/
Plainville area near Gillette Stadium
with a 115 - 13.8 kV 24/32/40 MVA
LTC transformer. Options: 1. Extend
Quick loadgrowth of Patriot Place
E-1 115 kV line from East Sub. 2.
Concept Mall may overload existing supply of
Construct a new 115 kV line from
23 kV and 13.8 kV.
West Walpole Sub. 3. Extend E-1 from
Easton Sub to West Walpole Sub with
a tap. 4. Construct new underground
115 kV line tapped off of C-181N/D182N to Crocker Pond Sub and
convert it to 115-13.8 kV.
LSP – Massachusetts Continued
Primary
Driver
Load Growth
2013
Load Growth
06/2013
Project
Current
Status
Quincy Area Field Street/North Quincy Supply
Upgrade
Upgrades
Concept
Marlboro Area 2nd 115-13 kV transformer at E.
Study
Main St. sub in Westboro
Concept
Needs Assessment
Need for this project is load growth
in the area of Quincy. The major
problems in the study area are
contingency overloads (130%) on
the 115-13.8 kV supply transformers.
Operating issues exist, such as the
inablity to switch and sectionalize the
115 kV supply system while it is
energized.
Solutions
At Field St., the existing T3 and T4, 11513.8 kV 40 MVA transformers will be
replaced with 55 MVA units. N. Quincy #11
substation will be expanded by adding two
additional 115-13.8 kV transformers, T3
and T4. Also 115 kV circuit switchers and
breakers will replace disconnect switches
to provide live line sectionalizing and
enhanced protection on the Edgar 532 and
533 lines that supply Field S. #1 and N.
Quincy #11 substations.
Due to Load growth need in area, a
second distribution transformer is 2nd 115-13.8 kV 40 MVA transformer
needed
Load Growth
06/2012
Avon area - new 115 - 13.8 kV
substation
Proposal of a new 115-13.8 kV substation
3 substations: Stoughton, Parkview, in Avon, MA. The transformer for the
Proposed and Ames will all be loaded above proposed Avon substation would be a 115
100% SN rating by summer 2012. - 13.8 kV 24/32/40 MVA with a summer
normal loading capability of 50 MVA.
Load Growth
06/2012
Dupont 115-13 kV Substation
Transformer Addition
Proposed
Norwell Sub replace 115-13 kV
transformer
The Norwell transformer was
operating at 104% of summer
normal rating during 2006. Norwell
Proposed
Sub has a transformer rated
15/20/25 MVA with a 28 MVA
summer-normal rating.
Load Growth
15
Projected InService
Month/Year Major Project
06/2011
Load Growth
07/2010
Load Growth
05/2011
Merrimack
Valley/North Re-conductor Meadowbrook - N.
Shore
Chelmsford portion of I-161 and AReliability 153 115 kV lines
Project
Extend existing E-1 115 kV line to
Mansfield Substation.
Planned
Planned
DuPont transformer will overload in
2010.
Add 2nd transformer with a summer normal
capacity of 60 MVA & 115 kV circuit
breaker.
Replacement of this transformer with one
rated 24/32/40 MVA with a summer-normal
rating of 50 MVA would provide an
increase of about 22 MVA.
Reconductor with 795 ACSR.
Mansfield Municipal Electric
An extension of E-1 is required to supply
Department plans to construct a new the new substation with a 115-13.8 kV, 44
115-13.8 kV substation.
MVA transformer.
LSP – Massachusetts Continued
Primary
Driver
16
Projected
In-Service
Month/Year Major Project
Area Reliability
Assessment
01/2010
Dist/Load Growth
Project
Current
Status
Merrimac, MA Municipal Install
23kV Loadbreak Transfer
Planned
2011
Palmer - install new 115/23 kV
transformer and circuit switcher.
Planned
Area Reliability
Assessment
2012
Webster St. - add three 115 kV
Western MA circuit switchers and new control
house.
Study
Planned
Area Reliability
Assessment
2015
West Amesbury
Carpenter Hill - install 115-69 kV 56
MVA autotransformer and low side
breaker.
Planned
Needs Assessment
Solutions
This project is part of a new 345-115
kV and 115-23 kV and 115-13kV
substation at West Amesbury. This
Replace line reclosers with loadbreak
project is part of the scheme. This
switches on the feed to Merrimac
was necessitated by changes in fault
Municipal.
duty and the reworking of the 23 kV
lines in the area of the new West
Amesbury substation.
Alternative 1 (planned): Install a 20
MVA 115-23kV transformer at
Palmer in year 2011. This
transformer will serve local 23 kV
See Western MA study
load in the Palmer area. Alternative
2: Convert the 23 kV distribution
system to 13 kV and install 115-13
kV transformer.
Alternative 1 (planned): Install 115
kV circuit switchers on high side of
Webster St 115-13kV transformers.
See Western MA study
Install new control house. Alt. 2
Install 115 kV ring bus with six 115
kV breakers at Webster St. Space
issues, as well as high cost.
Alternative 1 (planned): Install a 11569kV 56 MVA autotransformer at
Carpenter Hill in year 2015. This
transformer will function as the
primary 69 kV supply to E Webster
Substation. The backup supply to E.
See Western MA study
Webster will be from Millbury.
Alternative 2: Install a 4th 115-69kV
autotransformer at Millbury (may not
be sufficient space) in year 2015.
Also, install additional capacitor
banks at E Webster station.
LSP – Massachusetts Continued
Primary
Driver
Projected
In-Service
Month/Year Major Project
Area Reliability
Assessment
2012
Area Reliability
Assessment
2012
Area Reliability
Assessment
2012
Area Reliability
Assessment
2012
Area Reliability
Assessment
2012
Area Reliability
Assessment
2009
Area Reliability
Assessment
2011
Project
Replace the three existing, threewinding GSUs with two new twowinding 115-6.6 kV.
Install a new 115-69 kV,
33.6/44.8/56 MVA autotransformer
(No. 4) and a new 115-46 kV,
30/40/50 MVA autotransformer
(No. 5)
Remove the existing 69-46 kV, 8
MVA autotransformer (No. 3).
Install two new 115kV circuit
switchers (4T-115 and 5T-115)
Bellows Falls
Substation
Revitalization Install one new 69 kV GCB (G33).
Upgrade Line 4401 46 kV from
Vilas bridge to National grid/CVPS
demarcation point
17
2009
Planned
Planned
Planned
Planned
Planned
Planned
Planned
Bridge Street sub (GMP) remove
National Grid 6.9 kV transformer
Load Growth
Current
Status
Needs Assessment
Solutions
Alternative 1 (planned): Replace the
GSUs with two-winding units and add
new, independent transformers for
the 46 kV and 69 kV supplies, fed
directly from the 115 kV bus. This
option also includes the replacement
of 115 kV oil circuit breakers and oilfilled potential transformers.
Alternative 2: Maintain existing
Environmental concerns and
equipment. This alternative was not
asset conditions lead to the need
recommended as it would include
to replace the GSUs and much of
high transformer refurbishment cost
the switchyard equipment at
and it does not reduce the
Bellows Falls. Transmission
environmental and maintenance
planning studies have identified
risks, nor address asset separation.
the need to upgrade transmission
Alternative 3: Replace equipment in
facilities in the area including
kind. This alternative was not
certain Bellows Falls terminal
recommended due to the cost of
equipment. In addition these
replacement with increased ratings of
studies identified the need to
equipment, upgrades to equipment
install additional 46 kV and 69 kV
switching, protection and metering
transformation at Bellows Falls.
systems and it does not address the
separation of assets. Alternative 4:
Replace the GSUs with two-winding
units and install a single, three
winding 115-69-46 kV transformer.
This alternative was not
recommended because it creates a
single mode failure for two voltage
supplies.
Current transformer normal
Worcester Area Vernon Hill - Replace 2 115-13 kV
Construction loading at 100% of nameplate
Reinforcements transformers
rating.
Replace existing transformer with two
new 40 MVA 115-13 kV
transformers.
LSP – Massachusetts Continued
Primary
Driver
Point of Delivery
Request from
Customer
Load Growth
Load Growth
18
Projected
In-Service
Month/Year Major Project
12//2009
2010
05/2010
Project
Current
Status
Needs Assessment
Solutions
Alternative 1 (planned): 115-23 kV,
The proposed West Amesbury
55 MVA transformer & 115-13.8 kV,
Merrimack New W. Amesbury 115-23 kV and
substation will alleviate the loading 20 MVA transformer supply point at
Valley/North 115-13 kV substations tapped off
issue at King Street substation and West Amesbury. Alternative 2:
Construction
Shore Reliability of (394) line between Ward Hill and
the 23 kV sub-transmission lines and Extend two 115 kV lines from King
Project
Seabrook - King St. relief.
the 13.8 kV distribution circuits in the Street Substation, B-154N and Carea.
155N to a new 115-23 kV substation
at West Amesbury.
Worcester Area Cooks Pond Substation #23 - two
Reinforcements new 69-13.8 kV transformers.
Install 115 kV taps to Lynn
Substation from Q-169 & A-179.
Construction
Replace existing 10 MVA
transformers with 20 MVA
transformers.
Determined the need to remove the
existing 13.8 kV indoor substation
and install a new outdoor low profile
13.8 kV substation within the existing
Lynn #21 substation. Presently, Lynn
#21 substation is served via two
three-winding 115/23/14 kV
transformers #6 & #7. During
Construction
contingency loss of transformer #7,
the load on transformer #6 is
approaching 100% of its summer
emergency capability. The proposed
addition will alleviate potential loading
of the existing transformers during
contingency and will provide capacity
for future load growth in the area.
Alternative 1 (planned): Replace
existing 10 MVA transformers with
20 MVA transformers. Alternative 2:
Install additional distribution
breakers and circuits at Webster
Street #6 substation. Alternative 3:
Incerase distribution capacity at
Greendale #24 substation.
Install three new transformers 11513.8 kV 55 MVA nameplate rating for
the new proposed low profile
substation along with circuit
switchers and required relays for
protection schemes. Install the
proposed substation within the
existing Lynn #21 substation fence
by tapping the Q-169 and A-179 115
kV radial tap lines.
LSP – Rhode Island
Primary
Driver
Projected
In-Service
Month/Year Major Project
Current
Status
Project
Needs Assessment
Solutions
Rhode Island
Load Growth
2011
Load Growth
11/2012
Load Growth
06/2011
Load Growth
Load Growth
Pascoag - 2nd 13.8 kV feeder
Newport Area Newport Area Supply
Study
Reinforcements
Greater Rhode
Island
Transmission
Reinforcements
19
To address all distribution loading,
Proposed short circuit duty, reactive support
and reliability concerns through
2016.
2nd 13.8 kV feeder
Tap the 3763 line (69 kV) north of the
Newport Mall to supply a new
substation with 1 69 - 13 kV transformer
and 3 - 13 kV feeders.
Heavy loading issues on 23 kV &
Proposal of a new 115-12.5 kV
12.47 kV distribution systems in the
substation with a 115 - 12.5 kV
area of West Warwick, Coventry,
24/32/40 MVA transformer.
Warwick, and Cranston.
Proposed
Found concerns in SWRI area of
projected loading on feeders,
transformers, & dist. Supply lines in
New 115 - 13 kV Substation in SWRI
excess of summer
area with a 115 - 13.2 kV 24/32/40 MVA
normal/emergency capability.
transformer.
Woonsocket substation 115-13
kV transformer addition
Planned
Alternative 1 (planned): Install a 115-13
kV, 24/32/40 MVA transformer at
Provides permanent supply for
Woonsocket substation. Alternative 2:
growing load in NWRI to replace
Replace West Farnum 345-115-13 kV
temp 115-13 kV transformer at West
transformer. Alternative 3: Build
Farnum when tertiary winding failed.
permanent 115-13 kV switchyard at W.
Farnum.
New Hopkinton 115-13 kV
Substation
11/2010
Existing supply linie is approaching
its thermal limits.
Proposed
W. Warwick 115 - 12.5 kV Sub
06/2010
Concept
Area Reliability
Assessment
2012
Conversion of Jepson 69 kV
substation to 115 kV substation
Planned
See GRI Study
Area Reliability
Assessment
2012
Dexter Substation Changes
Planned
See GRI Study
LSP – Removed From 2008 List
Primary
Driver
Projected
In-Service
Month/Year Major Project
Project
Current
Status
Needs Assessment
Solutions
Removed from LSP - Completed
Point of Delivery
Request from
Customer
Rutland area new 115-13 kV
substation.
06/2009
Complete
Improve reliability to load.
Removed from LSP - Moved to RSP
Load Growth
New Devens 115 kV substation
See Solutions
This is a PTF solution to a local load
growth concern - Moved to RSP
Ayer substation install in-line 115
kV breaker
See Solutions
This is a PTF solution to a local load
growth concern - Moved to RSP
Convert 69 kV lines from Ayer to
Devens to 115 kV (Portion of U-21E See Solutions
and V-22E lines)
This is a PTF solution to a local load
growth concern - Moved to RSP
2011
Load Growth
2011
Load Growth
2011
20
Devens Area
Study
Local System Planning Process
Study Example
Study Area – Norwell C3 & S9 lines
 Norwell Area C3 & S9 115 kV transmission lines’ related
Loading and Reliability concern:
 Norwell area is located in the Southeastern part of
Massachusetts. It is presently served via C3 and S9 115 kV
transmission facilities out of Auburn Street substation in
Brockton, Massachusetts. Presently, the total load served via
the C3 and S9 lines is approximately 220 MW. Since, there are
only two 115 kV supply lines to the area, there is loading and
reliability concern during contingency loss of one of the two
supply lines to the area.
22
Norwell Area Map
23
System Impact Study (SIS) – Needs
Assessment
 Steady State analysis: Results of N-0, N-1 analysis – To evaluate the
steady-state reliability of the transmission system, summer peak load cases
were used: originated from ISO-NE 2007 library base cases and load levels
according to the ISO-NE CELT 2009 report, and National Grid’s 2009 PSA
forecast for the area. Thermal and voltage analysis were performed for all
facilities in service (N-0) and for all single contingency (N-1) applicable to the
area.
 Results of the steady state N-0 analysis did not show thermal and voltage related
issue in accordance to National Grid Transmission Planning Guide.
 Results of the steady state N-1 analysis did not show voltage related issue in
accordance to National Grid Transmission Planning Guide. However, 115 kV C3 line
showed possible thermal overloads during contingency loss of 115 kV S9 line for the
summer peak load case of 2012.
 Short-Circuit analysis: Results – will be performed only for the
recommended plan
 Transient Stability: Results – will be performed only for the recommended
plan
24
Present Layout – Norwell
The 115 kV radial C3 & S9 transmission lines
supply Norwell, Scituate, Plymouth Street,
North Abington, Phillips Lane, and Water
Street substations in the eastern portion of
Brockton Power Supply Area (PSA).
NO.ABINGTON
2.0
C3
2.7
3.0
6.3
2.7
6.3
S9
2.6
3.0
OP.
OP.
OP.
G
G
2.5
G
AUBURN. ST
NORWELL
PLYMOUTH.ST
PHILLIPS
LANE
WATER.ST
* The numbers in red background indicate approximate distances in miles
25
SCITUATE
Solutions – Norwell
26
Alternative 1:
Build a transmission line interconnecting C3 &
S9 lines with any nearby transmission line (e.g.,
478-509)
Alternative 2:
For higher reliability, CBs should be placed at
Water Street or Phillips Lane. Water Street is
ruled out due to space constraint. In-line CBs at
Phillips lane.
Alternative 3:
Ring bus at Phillips Lane to address reliability
related issues.
Alternative 4:
Both breakers at Phillips Lane and Switch closed
permanently at Norwell Sub to address reliability
related issues.
Solutions – Norwell
27
Alternative 1: Build a transmission line
interconnecting C3 & S9 lines with any nearby
transmission line (e.g., 478-509).
Solutions – Norwell
28
Alternative 2: For higher reliability, CBs should
be placed at Water Street or Phillips Lane. Water
Street is ruled out due to space constraint. Inline CBs at Phillips lane.
Solutions – Norwell
Alternative 3: Ring bus at Phillips Lane to
address reliability related issues.
29
Solutions – Norwell
Alternative 4: Add two breakers at Phillips Lane and
Switch closed permanently at Norwell Sub to
address reliability related issues.
30
Study Status
 Presently alternatives have been evaluated for Steady
state related analysis.
 Reliability related analysis is pending. Also, cost
estimates for alternatives have been requested from
various departments.
 Upon evaluating the alternatives, a recommendation
will be made for the alternative that best addresses
the area concern with the most cost effective
approach.
31
Questions
Questions
32