Access
Subscriptions for offtake and for injection Annual and monthly subscriptions for offtake and additional offtake power on a monthly basis: mechanism allowing optimisation of tariffs Subscriptions for offtake denote grid users’ power offtake forecasts. Subscriptions are submitted to Elia by the grid user itself1 or by the access holder designated by the grid user. The tariffs for use of the Elia grid apply, amongst other things, to subscriptions. A special feature of subscription tariffs is that there are cheaper tariffs for grid users whose actual offtakes closely match up with their subscriptions. It is therefore important for the grid user to have good knowledge of its offtake profile, as this will help it to tailor its subscription to its needs. This mechanism also means that Elia can make accurate forecasts of the use of its grid. Elia offers grid users tariffs for annual power subscriptions for offtake, monthly power subscriptions for offtake and tariffs for additional offtaken power on a monthly basis. Annual subscription tariffs are a more economical option than monthly subscription tariffs for long-term offtakes, whilst the tariff for additional power is always higher than the tariffs for power subscriptions. To help grid users decide on the size of their annual and monthly subscriptions, Elia provides them with a simulator that evaluates their bills on the basis of their offtake profile and the size of their subscription.
I. Optimising subscriptions: principles Elia uses the subscription-system as a basis for setting grid use tariffs (see the sheet "Objective, transparent and regulated grid access tariffs" for further details). Under this system, the grid user estimates the amount of power it expects to take off the highvoltage grid and informs Elia of these forecasts. If the grid user’s actual offtakes do not exceed its subscriptions, the user is billed for the power at the preferential subscription tariff rate. If the grid user’s actual offtakes exceed its subscriptions, it will be billed for the surplus offtaken power at the rate for additional offtaken power on a monthly basis, which is higher than the subscriptions rate. This mechanism encourages the grid user to fine-tune its subscriptions and consequently enables Elia to manage highvoltage grid use as efficiently as possible. The grid user must therefore be able to correctly evaluate the characteristics of its offtakes, and in particular peaks, as these peaks determine the power value.
I.1. The offtake profile: a key element To ensure that its subscriptions are as accurate as possible, it is therefore important for the grid user to have a good knowledge of its offtake profile. This profile may be flat, in which case there is hardly any fluctuation in offtake peaks in the course of a year; or there may on the contrary be major fluctuations in the profile (depending on, for example, the season or the time of day).
I.2. Three tariff categories Elia has different tariff categories to cover the wide range of offtake profiles: • tariffs for annual power subscriptions,for offtake based on an annual subscription; • tariffs for monthly power subscriptions for offtake, based on a monthly subscription; • tariffs for additional offtaken power on a monthly basis, which are applied if actual offtakes exceed subscriptions. For a flat offtake profile, the annual subscription tariffs are more economical than the monthly subscription tariffs. The grid user2 may submit valid annual and monthly subscriptions together. This flexible solution enables the user to optimise its access bill. There are three tariff periods for tariffs for monthly power subscription for offtake and for tariffs for additional offtaken power on a monthly basis: peak hours, off peak hours and weekend hours. The full range of grid access tariffs is published on the Elia website. Annual subscription for offtake in brief Annual subscription for offtake can be regarded as a power band covering a 12-month period. The grid user will take its expected consumption profile as its basis for setting this band and will opt for a subscription that is greater than or equal to its minimum offtake for the entire year, regardless of the circumstances. Elia is informed of this subscription power at least once year (no later than the twentieth day of the month before the start of the subscription period). In terms of billing, every month one-twelfth of the subscription is charged to the grid user’s account2. 1 2
as long as it has concluded an access contract with Elia or the access holder designated by the grid user
Monthly subscription for offtake in brief Monthly subscriptions for offtake enable the grid user2 to submit forecasts fine-tuned to its offtake profile. The profiles may fluctuate depending on when the grid user takes power from the grid and what its requirements are (requirements can fluctuate depending on how many orders it has to fulfil, etc.). Every month, and no later than the twentieth day of the month before the subscription period, the grid user2 informs Elia of its monthly subscription power. The monthly subscription may be combined with an annual subscription (which it complements). The combination of annual and monthly subscriptions enables the grid user to fine-tune its subscription strategy and vary its subscription power depending on, for example, the season and its activity schedule. Tariffs for additional offtaken power on a monthly basis in brief If the power actually taken off the grid by the grid user exceeds the (cumulative) level of its subscriptions, the tariff for additional offtaken power on a monthly basis is applied to the portion of offtake that exceeds the subscription. The tariff for additional offtaken power on a monthly basis adds up to 115 % of the tariff for monthly subscriptions for offtake. To establish the additional offtaken power on a monthly basis, Elia looks (on a quarter-hourly basis) at the power taken off the grid by the grid user.
I.3. Accurate subscriptions mean lower tariffs A grid user will always be billed for the subscription power, even if its actual offtake is lower. This means that it is very much in its interest: • not to overestimate its subscriptions, as this may lead to it being billed for power it doesn’t use; • not to underestimate its subscriptions, as this may mean that the tariff for additional offtaken power on a monthly basis will be applied - a tariff that is higher than the annual and monthly power subscription tariffs; • to strike the right balance between its annual and monthly subscriptions. As the grid user assesses well its consumption profile, it is able to fine-tune its subscriptions. The closer the match between actual offtakes and subscriptions, the lower the tariff it pays.
Subscriptions / actual offtake
actual offtake
additional offtaken power on a monthly basis
monthly subscription for offtake annual subscription for offtake
Time
Elia bills grid users monthly. In this period, Elia will not take the following into account for billing purposes: • the ten highest power offtake peaks during peak hours; • the five highest peaks during off-peak hours; • the five highest peaks during weekend hours.
I.4. Adjusting subscriptions to cope with unforeseen circumstances In specific circumstances, Elia may authorise the grid user to adjust its annual subscription. The objective is to enable the user to adapt to any major unforeseeable structural changes in its operations and being billed for a subscription that corresponds with its real offtake level. This facility is subject to strict conditions in order to stop it from being used for speculative purposes.
I.5. The simulator: a tool for optimising subscriptions for offtake For a flat offtake profile, the annual subscription tariffs are lower than the monthly subscription tariffs. This means that the grid user’s offtake profile must be used as a basis for finding the ideal balance between annual and monthly subscriptions. In order to make it easier to find this ideal balance, Elia has developed a simulator (available on its website) allowing users to forecast their bill based on their offtake profile and their annual and monthly subscription data. This means that the grid user can check how its choice of annual and monthly subscriptions affects its bill and adjust them if necessary.
II. Benefits of optimising subscriptions Optimising subscriptions has multiple benefits for the grid user: • the access holder pays the lowest tariffs by choosing a subscription that is tailored to its offtake profile; • the subscription procedure is simple and transparent and uses a secure, user-friendly platform; • the simulator is a particularly useful tool for helping the grid user to choose its annual and monthly subscription amounts; • the subscription system established by Elia is highly flexible. The grid user can choose between annual and monthly subscriptions. Under the annual subscription, grid users always have a basic package with the best tariff (for long-term offtakes), whilst a monthly subscription allows the user to factor in aspects such as seasonal variations, fluctuations in its order book and certain special features linked to the specific characteristics of the grid user’s activities. Moreover, grid users can combine annual and monthly subscriptions, giving them considerable flexibility to build up a subscriptions profile that closely matches up with its expected offtake profile.
III. Legal and contractual basis Managing access points to the Elia grid involves agreeing a grid access contract. Such a contract may be signed by the grid user or by an access holder designated by the grid user. Subscriptions are submitted to Elia by the access holder.
• Tariffs for use of the grid are applied, for example, to subscriptions submitted by grid users. Subscriptions are forecasts of the power that will be taken off the Elia grid. • For maximum flexibility, Elia offers specific tariffs for monthly and annual power subscriptions for offtake and a tariff for additional offtaken power. In order to take full advantage of this arrangement, a grid user must have full control over its offtake profile. • For long-term offtakes annual tariffs are lower than monthly tariffs. The grid user may combine monthly and annual subscription to enjoy the best tariffs. The tariffs for additional offtaken power are higher than the tariffs for power subscription for offtake. • In order to ensure that Elia’s grid users can deal with unforeseen circumstances, the highest offtake peaks are not considered in the Elia bill. • The simulator provided to grid users by Elia allows them to use their offtake profile to estimate the effect of their annual and monthly subscriptions on their bill.
Optimising subscriptions in 5 key points
A2-E-11.02.2012 / Non-contractual document / Editor: J. Vandermeiren, Bd de l’Empereur 20, 1000 Brussels
The system of tariffs for Elia grid access is based on the provisions of the CREG Decree relating to tariff methodology.