General Rules

Under Basic Storage Service, in a given Storage Group, Customers reserve Nominal Storage Capacity stated in MWh that gives a right to:

• Daily Nominal Injection Capacity stated in MWh/d, obtained by dividing the Nominal Storage Capacity by the Nominal Number of Days of Injection Service; and

• Daily Nominal Withdrawal Capacity stated in MWh/d, obtained by dividing the Nominal Storage Capacity by the Nominal Number of Days of Withdrawal Service

These rules are the same for all Customers within a given Storage Group. They are intended to make the exercise of each Customer's rights compatible with the combined physical characteristics of the underground storage facilities within that Storage Group with a view to maintaining performance. Additionally, they allow each Customer to benefit from injection and withdrawal capacities that are not contingent upon other Customers' requirements in that Storage Group.

For a given Customer in a given Storage Group, and except for special circumstances such as maintenance or force majeure, these rules mainly cover:

• Minimum Inventory and Maximum Inventory as the minimum and maximum quantities of gas to be held in storage according to the day of the year;
  
  

• Daily Injection Capacity and Daily Withdrawal Capacity that correspond to the maximum quantities of gas that the Customer may inject into or withdraw from storage according to his Storage Inventory;

• the possibility of reversing the direction of gas flow, i.e. switching from injection to withdrawal and conversely.

Minimum and Maximum Inventory

In a given Storage Group, each Customer's Storage Inventory must range between Minimum Inventory and Maximum Inventory on any day.

Minimum (or Maximum) Inventory for a Customer on a given day is equal to the Nominal Storage Capacity subscribed by the Customer multiplied by the Minimum (or Maximum) Inventory Level on the same day.

The values of Minimum (or Maximum) Inventory Level are specific to a Storage Group and are defined for every day of the year before the Storage Service Agreement takes effect (cf Storage Groups' Characteristics).

Daily Withdrawal Capacity

In a given Storage Group, the maximum quantity of energy that Gaz de France Stockage withdraws from storage to serve Customers on a given day, except for special circumstances, is the Daily Withdrawal Capacity.

Daily Withdrawal Capacity is calculated by multiplying Daily Nominal Withdrawal Capacity by the Nominal Withdrawal Capacity Reduction Factor.

The Nominal Withdrawal Capacity Reduction Factor is a coefficient that is dependent on the Customer's Inventory Level on the relevant day; it is specific to each Storage Group. (cf Storage Groups' Characteristics).

Daily Injection Capacity

In a given Storage Group, the maximum quantity of energy that Gaz de France Stockage injects into storage to serve Customers on a given day, except for special circumstances, is the Daily Injection Capacity.

Daily Injection Capacity is calculated by multiplying Daily Nominal Injection Capacity by the Nominal Injection Capacity Reduction Factor.

The Daily Nominal Injection Capacity Reduction Factor is a coefficient that is dependent on Customers' Inventory Level on the relevant day; it is specific to each Storage Group. (cf Storage Groups' Characteristics).

Reversing the Direction of Gas Flow

When, on a given day, gas is injected into (or withdrawn from) storage on a Customer's behalf and the Customer requests gas to be withdrawn from (or injected into) storage on the next day, Gaz de France Stockage will endeavor to do so on a reasonable-efforts basis.