Metering & Gas Quality Agenda.
1. Background & Context ExisIng Metering Systems
1. Orifice Plate
2. Ultrasonic
3. Turbine
2. SGN Management Governance Process 1. Metering & Gas Quality Team
2. Technician competency & Training
3. Planning processes
4. Maintenances & governance process
2
5
Orifice Plate meters Common meter for natural gas measurement
Originally developed in 1912
Wide size range (2” ….. 42” etc.)
O\akes built – 2 pre-‐1970, 18 between 1970 and 1979 (30 in total)
Pressure tappings measure changes in staIc pressure across the orifice plate
Flow rate ≈ ∫ (∆p )
6
Turbine meters
Flow rate ≈ ∫ (Speed of turbine ) k factors correct measured flow rate to validated figures
Typical k factor – 156451.93465
Scope for human error on input
USM’s – Why?
The compact design with integrated cable rouIng means that the measuring system is durable, failsafe, low-‐maintenance, and has long-‐term stability. The USM features extensive diagnosIcs opIons to allow detecIon of malfuncIons even before the measurement is affected. Types having 2, 4 or 4 + 4 measuring paths enable a variety of process applicaIons.
7
At a glance -‐ High efficient ultrasonic transducers Direct path layout Intelligent self-‐diagnos;cs Compact, robust design Integrated log book and data logger Large measuring range 1:120
Benefits -‐ Long-‐term stability, reliable measurement Low maintenance due to intelligent self-‐diagnos;cs Virtually immune to pressure regulator noise Ultrasonic transducers can be exchanged under opera;ng pressure Wide applica;on range
Typical OXake Metering System
8
Nat
iona
l Tra
nsm
issi
on S
yste
m
ROV
NGG UKT Pressure Reduction
Unit
Danalyzer
PinLo ∆P
Hi ∆P
SB ∆P
2551 Allen Bradley
Omni
HPMIS
GTMS
LGT
Local Transmission System
Flow Control ValveFCV
Offtake Metering System
SGN Network E&I -‐ Competency
9
Tom Ryan, Head of Network E&I
Shaun Stephenson, Metering Engineer
Annefe Murphy, Metering & Gas Quality (Admin)
E&I Technicians-‐ OperaIons. X ~ 15
Tom Noel, Network E&I
Engineer, South
Allan Balfour, Network E&I
Engineer, Scotland
10
SGN OXake Metering Systems Scotland
Site Meter Proposed
Upgrade
Glenmavis Orifice Plate > USM 2018 Bathgate USM 2005 Drum Orifice Plate > USM 2017 Broxburn Orifice Plate > USM 2019 Aberdeen Orifice Plate > USM 2020 Burnhervie USM 2009
Balgray Orifice Plate > Progn 2020 Armadale Orifice Plate N/A Soutra Orifice Plate N/A Lockerbie Orifice Plate N/A Kinknockie Turbine N/A Careston Turbine N/A Pitcairngreen Turbine N/A St. Fergus Turbine N/A Hume Turbine N/A Stranraer Turbine N/A Nether Howcleugh Turbine N/A Langholm Turbine N/A
South
Site Meter Proposed
Upgrade Hardwick Orifice Plate > USM 2019 Braishfield A USM N/A Winkfield SO Orifice Plate N/A Ipsden B Orifice Plate N/A Mappowder Orifice Plate > Prog 2020 Braishfield B USM N/A Ipsden A Orifice Plate N/A
South East
Site Meter Proposed
Upgrade Tatsfield Orifice Plate > USM 2016/17 Farningham Orifice Plate > USM 2029 Farningham B USM N/A
Winkfield SE Orifice Plate > USM 2018 Shorne Orifice Plate N/A
SGN OXakes – Scotland x 17
11
Torphichen
Fraserburgh
ST.FERGUSTERMINAL
ABERDEENO/T
BALGRAYO/T
ST.FERGUSO/T
KINKNOCKIEO/T
DRUMO/T
CARESTONO/T
to Ballylumford Power S
tation
Conon Bridge
Invergordon
Inverness
Dingwall
NairnForres
Elgin
Rothes
BuckieBanff
Turriff
Keith
HuntlyPeterhead
Banchory
Aberdeen
Newtonhill
Stonehaven
Inverbervie
Montrose
Arbroath
Brechin
ForfarAlyth
Pitlochry
Aberfeldy Logierait
Crieff
Dunkeld
Perth
Auchterarder
Newport
Langholm
Annan
Gretna
NewtonStewart
Dalbeattie
Kirkcudbright
Castle Douglas
Peebles
Innerleithen
Selkirk
Hawick
Oban IndependentUndertaking
CampbeltownIndependentUndertaking
Eyemouth (fed fromBerwick Upon Tweed)
ToBerwick Upon Tweed
Duns
Rothesay
Dunoon
Girvan
Maybole
South Ayr
North Ayr
West Kilbride
Largs
Kilmarnock
Muirkirk
Sanquhar
Haddington Dunbar
North Berwick
Pencuik Arniston
Leven
Crail
Cupar
St.AndrewsAuchtermuchty
Kirkcaldy
Callander
LethamMoss
Dunblane
Alloa
West Calder
BiggarLesmahagow
Lennoxtown
Cullen
StornowayIndependentUndertaking
Wick & ThursoIndependentUndertakings
to S
outh
ern
Irela
nd
Roche
System as at 1st Oct 2010
Dundee
KeyTerminal
CompressorNational Offtakes
NTS
70 bar44 bar39 bar32 bar28 bar19 bar12 bar<7 bar (IP/MP)Major PRSOperational Holder Station
N Independent Undertaking
Current Operating Pressures
PITCAIRNGREENO/T
EdinburghBlanefield
Erskine
Kilsyth
Kilbarchan
Greenock
Georgetown
Drakemyre
EagleshamOnthank
Burgie
Coachford
Maryculter
City GatePeterculter
LochmabenPriestdykes
Dumfries
Rhonehouse
Milton
Linlithgow
Grangemouth (Ind)
Fairmilehead
Kelso
Hume
Symington
Springside
Irvine
Dreghorn
Monkton
Carcluie
Provan
Bogton
Saline
Gestetner
Airth
TillicoultryRosebank
Kelty
Huntingtower
Guardbridge
Strathkinness
St Andrews
Glenrothes
Norbord
Stirling
Plean
Ecclesmachan
Newtongrange
Straiton
Aberlady
Musselburgh
Dalkeith
Tranent
Collessie
Balfarg
Lochgelly
Mossmorran
Bathgate
Bellshill
Prestwick
Wm Grant
Wishaw
Fallin
Old Kilpatrick
Milngavie
TorranceKirkintillochInverkip
BallingryW
estfield
Bathville
Kint
ore
Kemna
yW
esthi
lls Craibs
tone
Edzell
HUMEO/T
BROXBURNO/T
Cond
orra
t
Cum
bern
auld
C
Turnhouse
Granton
Mossend
Shieldhill
Winchburgh
Carleith
Hunterston
Uddingston
Motherwell
Crosshouse
Kittochside Cambuslang
Gartcosh
Newton Mearns
East Kilbride
Armadale
Waterfoot
Shawhead
Coldstream
Jedburgh
CGlasgowLivingston
Pencaitland
Moffat
TwynholmP.T.L.
Bord Gais Pipeline
S.N.I.P. (P
.T.L.)
Beattock
85 bar
Newarthill
250
250
250250
250
200
250
200
150300
300
300
250
100100
100
250
100150
200
150 100
300
200
450
450
200450
150
150 150
150
200300
300
300300
300
300
300
300
300
300
300
300
200
200
450
200
200
450
200
150150
450250
250 250
150
50250
250
150
250
200
200
300
200
200
100
450
450
450450
450
450200
200
450
450
300300
300
200
450450
450
250
300
300
300
450
300
250
250
250
250
400300
250
200300
250
250
150
100Troon
250150
250
150
150
1200
200
200
100
150
150
Galashiels
Dunfermline
Helensburgh
Paisley
Johnstone
450
Carfin
KirklistonDumbarton
100200
SOUTRAO/T
BATHGATEO/T
GLENMAVIS O/T
200
C
CC
C
C
N
N
NN
LANGHOLMO/T
NETHERHOWCLEUGH
O/T
STRANRAERO/T
LOCKERBIEO/T
Boll-o-Bere
250
250
150
ARMADALE O/T
200
150
450
Lauder
Paisley
Coatbridge
Kilmarnock
Newton-on-Ayr
Galashiels
Torphichen
Fraserburgh
ST.FERGUSTERMINAL
ABERDEENO/T
BALGRAYO/T
ST.FERGUSO/T
KINKNOCKIEO/T
DRUMO/T
CARESTONO/T
to Ballylumford Power S
tation
Conon Bridge
Invergordon
Inverness
Dingwall
NairnForres
Elgin
Rothes
BuckieBanff
Turriff
Keith
HuntlyPeterhead
Banchory
Aberdeen
Newtonhill
Stonehaven
Inverbervie
Montrose
Arbroath
Brechin
ForfarAlyth
Pitlochry
Aberfeldy Logierait
Crieff
Dunkeld
Perth
Auchterarder
Newport
Langholm
Annan
Gretna
NewtonStewart
Dalbeattie
Kirkcudbright
Castle Douglas
Peebles
Innerleithen
Selkirk
Hawick
Oban IndependentUndertaking
CampbeltownIndependentUndertaking
Eyemouth (fed fromBerwick Upon Tweed)
ToBerwick Upon Tweed
Duns
Rothesay
Dunoon
Girvan
Maybole
South Ayr
North Ayr
West Kilbride
Largs
Kilmarnock
Muirkirk
Sanquhar
Haddington Dunbar
North Berwick
Pencuik Arniston
Leven
Crail
Cupar
St.AndrewsAuchtermuchty
Kirkcaldy
Callander
LethamMoss
Dunblane
Alloa
West Calder
BiggarLesmahagow
Lennoxtown
Cullen
StornowayIndependentUndertaking
Wick & ThursoIndependentUndertakings
to S
outh
ern
Irela
nd
Roche
System as at 1st Oct 2010
Dundee
KeyTerminal
CompressorNational Offtakes
NTS
70 bar44 bar39 bar32 bar28 bar19 bar12 bar<7 bar (IP/MP)Major PRSOperational Holder Station
NN Independent Undertaking
Current Operating Pressures
PITCAIRNGREENO/T
EdinburghBlanefield
Erskine
Kilsyth
Kilbarchan
Greenock
Georgetown
Drakemyre
EagleshamOnthank
Burgie
Coachford
Maryculter
City GatePeterculter
LochmabenPriestdykes
Dumfries
Rhonehouse
Milton
Linlithgow
Grangemouth (Ind)
Fairmilehead
Kelso
Hume
Symington
Springside
Irvine
Dreghorn
Monkton
Carcluie
Provan
Bogton
Saline
Gestetner
Airth
TillicoultryRosebank
Kelty
Huntingtower
Guardbridge
Strathkinness
St Andrews
Glenrothes
Norbord
Stirling
Plean
Ecclesmachan
Newtongrange
Straiton
Aberlady
Musselburgh
Dalkeith
Tranent
Collessie
Balfarg
Lochgelly
Mossmorran
Bathgate
Bellshill
Prestwick
Wm Grant
Wishaw
Fallin
Old Kilpatrick
Milngavie
TorranceKirkintillochInverkip
BallingryW
estfield
Bathville
Kint
ore
Kemna
yW
esthi
lls Craibs
tone
Edzell
HUMEO/T
BROXBURNO/T
Cond
orra
t
Cum
bern
auld
C
Turnhouse
Granton
Mossend
Shieldhill
Winchburgh
Carleith
Hunterston
Uddingston
Motherwell
Crosshouse
Kittochside Cambuslang
Gartcosh
Newton Mearns
East Kilbride
Armadale
Waterfoot
Shawhead
Coldstream
Jedburgh
CGlasgowLivingston
Pencaitland
Moffat
TwynholmP.T.L.
Bord Gais Pipeline
S.N.I.P. (P
.T.L.)
Beattock
85 bar
Newarthill
250
250
250250
250
200
250
200
150300
300
300
250
100100
100
250
100150
200
150 100
300
200
450
450
200450
150
150 150
150
200300
300
300300
300
300
300
300
300
300
300
300
200
200
450
200
200
450
200
150150
450250
250 250
150
50250
250
150
250
200
200
300
200
200
100
450
450
450450
450
450200
200
450
450
300300
300
200
450450
450
250
300
300
300
450
300
250
250
250
250
400300
250
200300
250
250
150
100Troon
250150
250
150
150
1200
200
200
100
150
150
Galashiels
Dunfermline
Helensburgh
Paisley
Johnstone
450
Carfin
KirklistonDumbarton
100200
SOUTRAO/T
BATHGATEO/T
GLENMAVIS O/T
200
C
CC
C
C
NN
NN
NNNN
LANGHOLMO/T
NETHERHOWCLEUGH
O/T
STRANRAERO/T
LOCKERBIEO/T
Boll-o-Bere
250
250
150
ARMADALE O/T
200
150
450
LauderLauder
Paisley
Coatbridge
Kilmarnock
Newton-on-Ayr
Galashiels
St. Fergus
Aberdeen
Careston
Balgray
Drum
Pitcairngreen
Nether Howcleugh
Broxburn
Armadale
Drum
Soutra
Hume
Lockerbie
Langholm
Stranraer
Glenmavis
Bathgate
Kinknockie
Southern Sites
12
ShorneFarningham
Tatsfield
WinkfieldSo & SE
Hardwick
IpsdenA & B
BraishfieldA & B
Mappowder
SOUTHERN NETWORKS – OFFTAKE LOCATIONS
SOUTH EAST LDZ
SOUTH LDZ
13
Meter Valida;on SecIon 3 of the O\ake Arrangements Document under the UNC states:-‐ 3.1.3 Any validaIon of Measurement Equipment shall be carried out:
(i) by the downstream Party; GDN
(ii) in accordance with the provisions of … the ValidaIon Procedures; The Joint Office ME2 procedures
3.2.1 The downstream Party shall carry out validaIon:
(a) of the Measurement Equipment installed at an O\ake, no less frequently than once every 12 months;
3.4.2 The downstream Party shall provide the ValidaIon Report to the upstream Party: UKT
(i) no later than 14 days aper the compleIon of any RouIne ValidaIon
3.1.4 The upstream Party UKT shall be enItled, but shall not be obliged, at its own cost to afend and witness any validaIon carried out by the downstream Party in accordance with this paragraph 3.
14
Other Controls • Quarterly Gas Quality inspecIon by external body (SGS) contracted
to Ofgem
• Annual metering inspecIon by an external body (SGS) contracted to Ofgem
• Process agreed between Ofgem and DNs to provide a consistent approach
• Sample metering audits by external consultant for SGN • Current contractor -‐ Kelton
15
What is a Measurement Error O\ake Meter Errors result from:-‐
• Any “fault “ which results in a systemaIc bias to the measured quanIIes e.g.:-‐
• Orifice Plates -‐ contaminaIon, mis-‐alignment, incorrect plate dimensions, damage, incorrect direcIon..
• Turbines – bearing wear, fricIon, incorrect K factors
• USM -‐ incorrect K factors
• Flow Computer -‐ incorrect variables and/or configuraIon (viscosity, isentropic, temperature correcIon)
• Instrument drip
• Incorrect calibraIon of test equipment
• OperaIon outside the permifed range of the meter as specified within the “Supplemental Agreement”
Meter Error Reports
16
A Meter Error Report (MER) is raised whenever an error has been idenIfied
Triggered by a variety of mechanisms such as:
– Meter validaIon results
– Alarms detected by control systems
– Procedural errors idenIfied by site staff ReconciliaIon required if error is >0.1%
– Otherwise a null error
SGN Governance Processes
17
1. Planning
• Annual maintenance schedule as agreed with NTS
• SGN Governance Process– • Pre & Post flow checks
• Non RouIne operaIon
• Maintenance & spread sheet checks
• Competency & SGN Competency Assurance Scheme
2. Audit process
NTS Audit, 2 SGN sites per year
External auditors, 2 sites per year
Gas Examiner, quarterly visits
18
Our 6 Point Management Governance process
1. ValidaIons in accordance with UNC procedures and manufacturer’s instrucIons, controlled using pre-‐scripted Non-‐RouIne Procedures
2. Pre-‐ and post-‐validaIon checks to improved accuracy (< 3%) and robustly controlled
3. Orifice Plate Counters and InstrucIon Plates checked / refurbished -‐ complete
4. Work scheduling controlled and monitored
5. OperaIve Competency reviewed and confirmed through independent assessment
6. Robust training and briefing material delivered to all relevant personnel
19
Pre-‐ and Post-‐Checks, detail Need for verificaIon of conInued accuracy of the o\ake meter Actual in-‐day demand is not definable Cannot be specified for an individual o\ake (weather paferns etc.) No redundancy for elements of o\ake meters Many single items of equipment – orifice plate, ∆P tappings, flow computer • Incorrect placement of orifice plate corrupts all output • Failure to close ∆P cell equalisaIon valve corrupts output from all pressure cells Consider what to compare meter output (∆P) to? • PosiIon of flow control valve provides independent parameter • If P1, P2 and flow control valve posiIon unchanged, then flow rates will be similar
(albeit no temperature, density correcIon) In the event that a meter error is evident:-‐
• If site in ‘Set Point Control’, the flow control valve will open or close to allow the incorrect flow rate • If site in ‘Direct Valve Control’, valve posiIon will be unchanged, but meter will register a variaIon in flow
SGN Performance Repor;ng
20
Ref No.
Leading/Lagging Indicators
Definition of Measure Resp. Dir
Scotland
Southern
Rating Rating Remedial Action
PROG
RAMME M
EASU
RES I3
Annual Offtake Metering validation in accordance with programme
Validation of Offtake Metering systems completed within specified timescales
John Lobban, Paul Deniff
0 Green
0 Green
I4
Submission of offtake meter validation reports to Upstream Party within 14 days
Submission of validation reports to NGG UKT within 14 days of validation completion
John Lobban, Paul Deniff
0 Green
0 Green
OFFTAK
ES AND
ENTR
Y POINT
S
D2 Avoidance of offtake metering errors
Offtake meters errors -‐ instances of self-‐inflicted error
Paul Denniff
0 Green
0 Green
D3
Magnitude of offtake metering errors (less than 0.05% of LDZ transported volume p.a.)
Instances of meter error exceeding 0.05% of LDZ transported volume p.a.
Paul Denniff
0 Green
0 Green
21
Visibility -‐ RIIO GD1 Price Control Review for 8 years commenced 2013 focusing on Revenue linked to InnovaIon, IncenIves and Outputs
Output to monitor number and energy value of meter errors.
May differenIate by:-‐
• Equipment Failure
• Maintenance Error
Normalise by Local DistribuIon Zone
PotenIal to incenIvise Networks on performance
Stakeholder engagement
OFGEM MER Output – GD1
22
Possible measurement errors for these meters are clearly defined. When an error occurs, it is incumbent upon the transporter to calculate the scale of the error and arrange for reconciliaIon of the error. Actual performance baseline is defined as:-‐
• ∑ (all measurement errors for network)
• ∑ (energy throughput for network)
• GDNs suggest performance of 99.9% is generally achievable
Meter Errors
Southern
2006-7 2007-8 2008-9 2009-10
2010-11
2011-12
2012-13
2013-14
2014-15
0.000% 0.000% 0.001% 0.828% 0.354% 0.006% 0.000% 0.000% 0.000%
Scotland
Meter Errors
2006-7 2007-8 2008-9 2009-10
2010-11
2011-12
2012-13
2013-14
2014-15
0.000% 0.012% 0.013% 4.098% 2.141% 0.009% 0.000% 0.000% 0.000%
Thank you – Any further Ques;ons email -‐ [email protected]
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