Ancillary services

Overview

Since Elia does not have its own facilities on which it can alter injection or offtake, it buys flexibility capacities, or reserves, from generators and consumers to ensure the reliability of the high-voltage grid and the quality of the energy supply. The services provided in this way are known as Ancillary Services.

Elia uses Ancillary Services products) to balance the grid (primary, secondary and tertiary reserves), but also to maintain the stability in grid in case of need (MVAR and Black Start services).

Balancing Ancillary Services (AS) can be provided by generation as well as load facilities connected to the TSO or DSO grid depending on the AS product; exceptionally this can be done as well by flexibility at neighboring transmission system operators. Elia can also buy these Ancillary Services from generation units that hold a valid CIPU[1] contract or Non-CIPU grid users.

The MVAR and Black Start services are only provided by CIPU power units.

See here more information on how Ancillary Services help Elia balance the grid.

 

How can I know if I can offer balancing services to Elia?

Sites offtaking or injecting energy on the transmission grid (or even the distribution grid for some products) can offer their services to Elia directly or via an aggregator as far as they can meet some basic requirements for each of Elia’s products.

The most basic technical requirements for balancing product are reaction time2, activation duration3, minimum time between consecutive activations and maximum number of activations per delivery period4. For more details on all products requirements you are invited to consult contractual documents available here .

Hereby under is an overview of these characteristics for Elia’s balancing products:

Product

Availability

Reaction time

Maximum duration of activation

Time between activations

Maximum number of activations

TSO/DSO connected users ?

R1 CIPU

100% (15min average)

30sec

Constant

-

-

TSO&DSO

R1 Non-CIPU

100% (15min average)

30sec

Constant

-

-

TSO&DSO

R2

100% (15min average)

7,5min

Constant

-

-

TSO&DSO

R3 CIPU

100% (15min average)

15min

8h/day (Standard Service Type)

-

Unlimited

TSO&DSO
2h (Flex Service Type) 12h 8 per month

R3 Non-CIPU

100% (15min average)

15min

8h/day (Standard Service Type)

-

Unlimited

TSO&DSO
2h (Flex Service Type) 12h 8 per month

ICH

100% (1 year average)

3min

2/4/8 hours*

24h

4/12 per year*

TSO
R3 Non-Reserved None outside offered periods 15min Depending on offer, maximum 2 hours Depending on offer Depending on offer TSO 

* Depending on the choice of the provider

Please note that Elia is obliged to constantly develop and improve its products, so product characteristics might evolve over time.

More information on programmed evolutions can be found here  or can be asked by email at contracting_as@elia.be.  

1 Coordination for Injection of Production Units contract concluded between Elia and generators connected on Elia’s grid

2 Time in which a supplier can modulate his injection or offtake to its full extent after having received an activation notification by Elia

3 Maximum activation time that can be requested by Elia for one activation

4 Can be a week, month or year depending on the product

 

Why take part?

By supplying ancillary services, grid users become actively involved in managing and helping to ensure the efficient operation of the Elia grid. You benefit from cost optimization because it lowers Elia's costs and those costs have a direct impact on Elia's consumption tariffs.

More efficient operation also enables Elia to better scale its investments in grid infrastructure, which in turn has a positive impact on Elia tariffs.

Also, at the very least, the compensation paid by Elia can cover grid users' costs for providing ancillary services.