National Instantaneous

1

• National Instantaneous
• Reserves Market
• Vladimir Krichtal
• Transpower New Zealand

2
HVDC transfer model
Power transfer
NI
SI
Reserves Transfer
3
Economics behind reserve transfer
Reserve price function
New Reserves price function
Reserves price
Reserve Revenue saving
Reserve price decrease
Reserve price
New Reserve price
Risk
Reserves
0
Local Reserves cleared
Reserves Import
4
Frequency Stabiliser and Instantaneous Reserves
Sharing
Reserves sharing (MW)
Frequency stabiliser dynamic
Instantaneous reserves sharing
Guaranteed reserves sharing level
250 MW
Time (sec.)
30sec
5
HVDC load duration curve reserves transfer
ability
800
Power transfer
NI reserves transfer
250
North received (MW)
Amount of time ()
0
50
0
100
-250
SI reserves transfer
-400
6
Structure of power and reserves flows at the HVDC
line
NI Reserves RampUp
NI reserves transfer
Power dead band
Power flow limit - stable state
Power flow limit overload
NI SI Modulation Limits
0
NI power transfer
SI Reserves RampDown
SI reserves transfer
7
Existing Risk-Reserve model
Gn Risk
G1 Risk
Manual Risk
GEN
GEN
HVDC
Biggest Zone Risk max(G1,..,Gn,Man,DCE,DCECE) G
1
DC Risk
Islands Reserve Price
ILR
Zone Res. pool
8
New Reserves model

• HVDC reserves transfer capability. Using
  instantaneous reserves from one reserve zone to
  cover generation risks in the other reserve
  zone.
• New reserves price structure.

9
Proposed Risk-Reserves model
G2 Risk
G1 Risk
Manual Risk
GEN
GEN
G1 Res pool price
G1 Res pool price
G1 Res pool price
G1 Res pool
HVDC
G2 Res pool
Man Res pool
DC Risk
ILR
G1 Res pool price
HVDC Res pool
Res Export
Res Import
10
New Reserves model (1)
11
New Reserves model (2)
12
Reserve transfer constraints (1)
13
Reserve transfer constraints (2)
14
Zonal reserve price
15
Old- New Reserves Revenue Difference
16
The SPD model prototype

• HVDC configuration aggregation.
• HVDC Losses adjustment.
• Estimating parameters of HVDC reserve transfer
  capabilities.
• The SPD prototype coding for simulation a new SPD
  model with HVDC reserve transfer ability.

17
Reduction of Energy and Reserves revenue and cost

• Reserves sharing between islands.
• Co-optimisation between Energy and Reserves .
• Applying shadow price of each binding risk in
  case of multiple risk contingency instead of one
  price for each reserve zone.

18
Revenue Difference (May 2004)
19
Total Cost Difference (May 2004)
20
Results

• Total revenue saving reaches 9.6m. over 4
  months.
• Net economic benefit reaches 0.68m. over 4
  months.