Explanatory material

METHODOLOGY ON CROSS-ZONAL CAPACITY CALCULATION AND ALLOCATION WITH THIRD COUNTRIES Methodology on cross-zonal capacity calculation and allocation with third countries

LITHUANIA-KALININGRAD CROSS- ZONAL CALCULATION LITHUANIA- CROSS-ZONAL CALCULATION PRINCIPALS PRINCIPALS Total Transfer Capacity (TTC) Net transfer capacity Net transfer capacity calculation (NTC) calculation (NTC) calculation Technical flow Technical limitations calculation criteria calculation criteria

D-1 planning stage According to paragraph 1 Based on good practices According to paragraph 1 of Article of Article 4 of Lithuanian applied by neighboring TSO‘s 4 of Lithuanian Law on Necessary Law on Necessary Measures Measures of Protection against the of Protection against the Threats Posed by Unsafe Nuclear Threats Posed by Unsafe Power Plants in Third Countries Nuclear Power Plants in Third Countries

During annual, During D-1 During real During annual, monthly, D- monthly, D-2 planning planning stages time 2, D-1 planning stages stages operation Lithuania-Kaliningrad cross-zonal net transfer capacity (NTC) calculation

NTCRU-LT= MIN((TTCRU-LT-TRM); (GRU-PRU))

Network capacity criterion Balance criterion depends on line status

Where:

NTCRU-LT –Lithuania- (Kaliningrad Region) cross-zonal Net transfer capacity;

TTCRU-LT –Maximum transfer capacity in the Lithuanian direction according to the instruction of parallel operation in the Lithuania-Russia (Kaliningrad Region) cross-border interconnection; TRM –the transfer reliability limit at the interconnection, jointly set by Lithuanian and Russian TSOs;

GRU –Russian (Kaliningrad Region) production according to D-2 balance plans;

PRU –Russian (Kaliningrad Region) load according to D-2 balance plans.

• Lithuanian-Kalingrad NTC calculation principles correspond current situation

• 2021 Statistical average of NTCRU>LT= 218MW Technical flow calculation in the interconection BY-LT Need for technical flow setup: Taking account of the provision of the Law that the electricity market of the Republic of Lithuania may not be accessed by A B C (transit flow BY>RU) Visulahli Visulahli Ulvila Kangasala Ulvila Kangasala Visulahli electricity from third countries where Ulvila Kangasala Huittinen Huittinen Huittinen Vyborgskaya Vyborgskaya Rauma Hikia Yllikkala Rauma Hikia Yllikkala Forssa Kamennogorslaya Forssa Kamennogorslaya Hikia Vyborgskaya Koria Koria Rauma Yllikkala Kymi Kymi Forssa Kamennogorslaya Hyvinkaa Hyvinkaa Koria Kymi Lieto Nurmijarvi Lieto Nurmijarvi Hyvinkaa unsafe nuclear power plants operate, with Dannebo Anttila Dannebo Anttila Nurmijarvi Lieto Anttila Salo Tammisto Landisalmi Salo Tammisto Landisalmi Dannebo Kopula Kopula Salo Tammisto Landisalmi Espoo Espoo Kopula Espoo the exception of the energy necessary to Tuna Tuna Tuna Hamra Hamra Gatchinskaya Leningradskaja Gatchinskaya Leningradskaja Hamra Gatchinskaya Leningradskaja Vallentuna Vallentuna Rakvere Pussi Kingsepp Rakvere Pussi Kingsepp Aruküla Aruküla Vallentuna Rakvere Pussi Kingsepp ensure the reliability of the electricity Harku 52 MW Harku Aruküla Stocholm Stocholm Harku Kiisa Kiisa Kolbotten Ekudden Kolbotten Ekudden Stocholm Ekudden Kiisa Hall Hall Kolbotten Hall Luzhskaya EE Luzhskaya Paide Paide Luzhskaya system of the Republic of Lithuania, the EE EE Paide Yugo-Zapachaja Yugo-Zapachaja Tartu Tartu Sindi Sindi Tartu Yugo-Zapachaja Sindi

Kilingi-Nõmme Kilingi-Nõmme Methodology defines the components of the Kilingi-Nõmme

Tsirguliina Tsirguliina Pskov Tsirguliina Pskov

Velikorecnaja Velikorecnaja Dundaga -110 MW Dundaga Velikorecnaja Valmiera Valmiera Dundaga technical flow Valmiera Gotland Gotland Ventspils Ventspils Gotland Ventspils

Riga Riga Tume Tume Imanta Imanta Tume Bisuciems Salaspils Bisuciems Salaspils Imanta 73 MW Bisuciems Salaspils Broceni Broceni Broceni Aizkraukle Aizkraukle Jelgava Rezekne Jelgava Rezekne Aizkraukle Grobina Krustpils Grobina Krustpils Jelgava Rezekne LV LV Grobina LV Krustpils Novosokolniki Novosokolniki Technical flow consist of: Novosokolniki Telšiai Mūša Telšiai Mūša Telšiai Mūša NordBalt Liksna NordBalt Liksna NordBalt Liksna Šiauliai Daugavpils Šiauliai Daugavpils Šiauliai Daugavpils Klaipėda Klaipėda Panevėžys Panevėžys Klaipėda Panevėžys Utena Utena A. The balancing energy purchased and IAE IAE Utena 27 MW IAE Šyša Šyša Šyša 26 MW Postavy Postavy Postavy Polock Polock Polock LTJurbarkas LTJurbarkas Vitebsk Bitėnai Bitėnai LTJurbarkas Vitebsk Bitėnai Jonava Jonava Jonava Garliava Garliava 74 MW Sovietsk Sovietsk Garliava sold by the TSO from other TSOs to Kaunas Kaunas Sovietsk Kaunas Neris 58 MW Neris Neris LE LE Severnaya-330 KHAE Severnaya-330 KHAE Severnaya-330 KHAE LE Orsha Orsha Żarnowiec Żarnowiec Żarnowiec Orsha N. Vilnia N. Vilnia N. Vilnia Vilnius Vilnius Vilnius Tsentralnayna Alytus Tsentralnayna Alytus Tsentralnayna Alytus Smorgon Smorgon Smorgon Gdansk BtB Gdansk BtB Gdansk BtB Gdansk Gdansk Gdansk compensate for the imbalance in the Borisov Mogilev Borisov Mogilev Mogilev Blonia Blonia Blonia Borisov Severni Severni Severni

Molodechno Molodechno Molodechno Minsk Mogilev 330 Minsk Mogilev 330 Minsk Mogilev 330 Elk Mink Vostochnoje Elk Mink Vostochnoje Elk Mink Vostochnoje Sevemaj Sevemaj Sevemaj Olsztyn Olsztyn Olsztyn Olsztyn Olsztyn Olsztyn Lida Lida Lida Matki Matki Matki Baltic ES; Grodno Grodno Kolijadichi Kolijadichi Kolijadichi B. Electricity flows between electricity systems for the purpose of electricity exchange, including electricity transit, shall be carried out in accordance with C (loop flow RU>RU) C (transit flow RU>Kal) D

Visulahli Ulvila Kangasala Visulahli Visulahli Ulvila Kangasala Ulvila Kangasala

Huittinen the joint agreements of the Huittinen Huittinen Vyborgskaya Rauma Hikia Yllikkala Kamennogorslaya Hikia Vyborgskaya Hikia Vyborgskaya Forssa Rauma Yllikkala Rauma Yllikkala Forssa Kamennogorslaya Forssa Kamennogorslaya Koria Kymi Koria Kymi Koria Kymi Hyvinkaa Hyvinkaa Hyvinkaa Lieto Nurmijarvi Dannebo Anttila Lieto Nurmijarvi Lieto Nurmijarvi Dannebo Anttila Dannebo Anttila transmission system operators of the Salo Tammisto Landisalmi Salo Tammisto Landisalmi Salo Tammisto Landisalmi Kopula Kopula Kopula Espoo Espoo Espoo

Tuna Tuna Tuna Baltic capacity calculation region on Hamra Leningradskaja Hamra Hamra Gatchinskaya Gatchinskaya Leningradskaja Gatchinskaya Leningradskaja

Vallentuna Rakvere Pussi Kingsepp Vallentuna Vallentuna Aruküla Rakvere Pussi Kingsepp Rakvere Pussi Kingsepp Aruküla Aruküla Harku Harku Harku Stocholm Stocholm Kiisa Stocholm Kolbotten Ekudden the calculation and allocation of Ekudden Kiisa Ekudden Kiisa Kolbotten Kolbotten Hall Hall Hall Luzhskaya Luzhskaya Luzhskaya Paide capacity of the connecting links; EE Paide Paide EE Yugo-Zapachaja Yugo-Zapachaja Tartu Tartu Yugo-Zapachaja Tartu Sindi Sindi EESindi 47 MW Kilingi-Nõmme C. Transit and loop electricity flows Kilingi-Nõmme Kilingi-Nõmme Tsirguliina Pskov Tsirguliina Pskov Tsirguliina Pskov

Velikorecnaja Velikorecnaja Velikorecnaja Dundaga Dundaga Dundaga Valmiera Valmiera Valmiera Gotland Gotland 86MW Gotland Ventspils between third country operators due to Ventspils Ventspils -700MW Riga Riga Riga Tume Tume Tume Imanta Imanta Imanta Bisuciems Salaspils Bisuciems Salaspils Bisuciems Salaspils Broceni the configuration of the existing Broceni Broceni Aizkraukle Aizkraukle Aizkraukle Rezekne Jelgava Rezekne Jelgava Rezekne Jelgava Krustpils Grobina LV Krustpils Grobina Krustpils Grobina LV Novosokolniki LV Novosokolniki Novosokolniki

Mūša Telšiai Mūša Telšiai Mūša Telšiai synchronous zone energy system grid NordBalt NordBalt NordBalt Liksna Liksna Liksna Šiauliai Daugavpils Šiauliai Daugavpils Šiauliai Daugavpils

Klaipėda Klaipėda Klaipėda Panevėžys Panevėžys Panevėžys Utena Utena Utena IAE IAE 390 IAE

14 MW Šyša Šyša infrastructure Šyša Postavy Postavy Postavy Polock Polock Polock Jurbarkas Jurbarkas LTJurbarkas Vitebsk Vitebsk Bitėnai Vitebsk Bitėnai Bitėnai Jonava LT Jonava Jonava Garliava Sovietsk Garliava Sovietsk MWGarliava Sovietsk Kaunas Kaunas Kaunas Neris Neris Neris Severnaya-330 KHAE LE Severnaya-330 KHAE LE Severnaya-330 KHAE LE D. Electricity flows required to ensure Orsha Orsha Orsha Żarnowiec Żarnowiec Żarnowiec N. Vilnia N. Vilnia N. Vilnia Vilnius Vilnius Vilnius Tsentralnayna Alytus Tsentralnayna Alytus Tsentralnayna Alytus Smorgon Smorgon Smorgon Gdansk BtB Gdansk BtB Gdansk BtB Gdansk Gdansk Gdansk Mogilev Blonia Borisov Mogilev Blonia 53 MW Borisov Blonia Borisov Mogilev Severni Severni Severni synchronous zone frequency control Molodechno Molodechno Molodechno Minsk Mogilev 330 Minsk Mogilev 330 LT Minsk Mogilev 330 Vostochnoje Elk Mink Vostochnoje Elk Mink Elk Mink Vostochnoje Sevemaj Sevemaj Sevemaj Olsztyn Olsztyn Olsztyn Olsztyn Olsztyn Olsztyn Lida Lida Lida Matki Matki Matki Grodno Grodno Grodno and emergency response Kolijadichi Kolijadichi Kolijadichi Calculataion of Technical limitations of BY-LT interconection

The technical Lithuania-Belarus cross-zonal capacity is calculated using the Common grid model, according to Formula 3, considering the planned power lines disconnections:

TP= MIN ((Pstat*0,8); (Pn-1*0,92);Pn-1term.;PU;PUn-1 ;Pdyn) (Formula 3)

Where: TP – Technical transfer capacity of Lithuania-Belarus cross-border interconnection; (Pstat*0.8) - maximum active power flow through the Lithuania-Belarus cross-border interconnection in the case of a normal scheme according to the static stability criterion, considering the 20 % reliability ratio (Pn-1*0.92) – maximum active power flow through the Lithuania-Belarus cross-border interconnection in the N-1 situation according to the static stability criterion, considering the 8 % reliability ratio (Pn-1term) - maximum active power flow through the Lithuania-Belarus cross-border interconnection in the N-1 situation, considering the thermal capacity of the power lines; (Pu) - maximum active power flow through the Lithuania-Belarus cross-border interconnection in the case of a normal scheme, considering the 15 % voltage reliability ratio; (PUn-1) - maximum active power flow through the Lithuania-Belarus cross-border interconnection in the N-1 situation, considering the 10 % voltage reliability ratio; (Pdyn) – maximum active power flow through the Lithuania-Belarus cross-border interconnection, considering the dynamic stability criterion Lithuania-Belarus cross-zonal TTC calculations during D-1 planning

Technical flow consist of: A. The balancing energy purchased Lithuania-Belarus cross-zonal TTC in direction to Lithuanian ES during D-1 and sold by the TSO from other planning is calculated for every hour according to Formula 8: TSOs to compensate for the imbalance in the Baltic ES; B. Electricity flows between electricity systems for the TTCBY>LT(i)=MIN [(Ptech(i)+Prez); TP(i)] (Formula 8) purpose of electricity exchange, including electricity Technical limitations transit, shall be carried out in P =P*k Ptech(i)=PBY>LT(i) rez depends on line status accordance with the joint agreements of the transmission system operators of the Baltic Average Sum of Technical flow b) and Technical flow a) and d) (According 2020 c) components= 131 MW components=164 MW capacity calculation region on statistical data) the calculation and allocation of capacity of the connecting links; Range From: 0 MW 164 MW C. Transit and loop electricity (According 2020 To: 875 MW flows between third country statistical data) operators due to the configuration of the existing synchronous zone energy system grid infrastructure D. Electricity flows required to LT-BY TTC calculation is based on determination of technical flow and verification that technical ensure synchronous zone flow does not exceed the technical limitations. frequency control and emergency response Lithuania-Belarus cross-zonal net transfer capacity (NTC) calculation

Visulahli Ulvila Kangasala

Huittinen

Vyborgskaya Rauma Hikia Yllikkala Forssa Kamennogorslaya Koria Kymi Hyvinkaa Nurmijarvi In order to implement provisions of paragraph 1 of Article 4 Lieto Anttila Dannebo

Salo Tammisto Landisalmi Kopula Espoo of Lithuanian Law on Necessary Measures of Protection Tuna

Hamra Gatchinskaya Leningradskaja

Vallentuna Rakvere Pussi Kingsepp Aruküla Harku against the Threats Posed by Unsafe Nuclear Power Plants in Stocholm Kiisa Kolbotten Ekudden Hall Luzhskaya Third Countries, which provide that electricity from third EE Paide

Tartu Yugo-Zapachaja Sindi countries with unsafe nuclear power plants, with the Kilingi-Nõmme Tsirguliina Pskov

Velikorecnaja Dundaga Valmiera Gotland exception of the energy necessary to ensure the reliability of Ventspils

Riga

Tume Imanta Bisuciems Salaspils the electricity system of the Republic of Lithuania, cannot Broceni Aizkraukle LV Jelgava Rezekne Grobina Krustpils

Novosokolniki

Telšiai Mūša NordBalt enter the electricity market of the Republic of Lithuania, Liksna Šiauliai Daugavpils Klaipėda Panevėžys Utena LT IAE Šyša Postavy cross- zonal NTC of BY-LT shall be defined 0 MW. Polock Jurbarkas Bitėnai Vitebsk Jonava Soviets k Garliava Kaunas NTC=0 MW Neris Severnaya-330 KHAE LE Żarnowiec Orsha N. Vilnia Vilnius Tsentralnayna Alytus Smorgon Gdansk BtB Gdansk Blonia Borisov Mogilev Severni

Molodechno Minsk Mogilev 330 Elk Mink Vostochnoje Sevemaj Olsztyn Olsztyn Lida Matki Grodno Kolijadichi Additional slides Technical flow calculation principals (I) (during D-1 planning stage) The sum of technical flow components (b) and (c) for each Technical flow consist of: hour will be determined by simulating the physical flows in the a) The balancing energy purchased and sold by the TSO from other TSOs to compensate for the imbalance in the Baltic ES; BRELL loop b) Electricity flows between electricity systems for the purpose of electricity exchange, including electricity transit, shall be carried out in accordance with the joint agreements of the transmission system operators of the Baltic capacity calculation region on the calculation and allocation of capacity of the connecting links; c) Transit and loop electricity flows between third country operators due to the configuration of Calculation input data: the existing synchronous zone energy system grid infrastructure d) Electricity flows required to ensure synchronous zone frequency control and emergency • The balance data of the Baltic systems of the previous response day shall be used. • Network models and forecast system balances provided by Russian and Belarus TSO‘s during D-2 planning stage shall be used.

If the aggregate balance of the Baltic ES, including direct current connections and imports from Kaliningrad, is in deficit at the appropriate hour in this case generation of the deficit Baltic ES is proportionally increased, the proportion of the increase in generation shall be determined in accordance with formula 7: P(i)=B(i)/Bsum ( Formula 7) Where: Performance of power P(i) - i-th increasing ratio factor of Baltic energy system, which is in flow calculation in order deficit; to define power flow via B(i) - i-th Baltic energy system balance, which is in deficit BY-LT interconnections (difference between generation and demand, assessing the direct by using common BRELL current connections), MW; network model Bsum - sum of Baltic ES balances, which are in deficit, MW. Technical flow calculation of b) and c) components (II) (during D-1 planing stage) Example Initial planning system balances

System name Initial balance, MW Estonian ES 100 Latvian ES generation increase coeficient-0,1 (according formula 7) Latvian ES -50 Lithuanian ES -500 Lithuanian ES generation increase coeficient-0,9 Kaliningrad ES 200 (according formula 7) Aggregated balance -250 Aggregated Baltic deficit including DC links System balances used in the calculation

System name Final balance, MW Estonian ES 100 Baltic aggregated balance =0 MW Latvian ES -25 Lithuanian ES -275 Kaliningrad ES 200 Aggregated balance 0

The sum of the technical flows components (b) and (c) shall be calculated by power flow simulation at the appropriate hour. The sum of the technical flows (b)and (c) of the components is equal to the active power flow in BY-LT interconection PBY>LT =131 MW

Depending on the technical flow of electricity exchange between Russian PS‘s and Belarus PS, the sum of the b) and c) components may vary from 0 MW to 875 MW (avg.131 MW) (Acording 2020 statistical data) Total Transfer Capacity (TTC) calculation (III) (during D-1 planning stage) Example

TTCBY>LT(i)=MIN [(Ptech(i)+Prez); TP(i)]

P =P*k Technical limits depends on line Ptech(i)=PBY>LT(i) rez status (for this example 700 MW value is used)

Sum of technical flows Technical flows (a) and (d) (b) and (c) components= components calculation 131 MW( see. slide 9)

P=Pmax-PLT

Where:

Pmax –biggest active power source of Lithuanian ES ( Nord BaLT -700 MW) PLT- amount of frequency restoration reserve ensured in Lithuanian ES (390 MW) k – reserve distribution coefficient via BY-LT interconnection (0,53). Prez=310*0,53=164 MW

TTCBY>LT=MIN [(131+164); 700]=295 MW