Background and current situation
What does ‘forecast’ mean in the energy sector?
The term ‘forecast’ literally means ‘prediction’.
In the renewable energy sector, it refers to the prediction of electricity production from a solar or wind power plant, generally in the short term, from D+1 to D+8.
In practical terms, this involves estimating in advance the amount of energy that a power station will feed into the electricity grid, so that the various stakeholders (producers, grid operators, aggregators) can anticipate and manage the balance of the system.
On what data is the production forecast based?
Production forecasting is based on two main components:
- Forecast meteorological data: solar radiation, wind speed and direction, temperature, etc.
- A power plant production model, similar to a digital twin, which converts this climate data into forecast energy (kWh).
This weather data is fed into a physical model specific to each installation (technology, power, orientation, efficiency, etc.), which enables a realistic estimate of future production.
What is the purpose of forecasting today?
Who uses Forecast on a daily basis?
Today, Forecast is mainly used to meet the requirements of network operators.
These operators need to know the quantities of energy that will be fed into the network on D+1 in order to anticipate:
- Electricity flows,
- Transport constraints,
- The regulatory mechanisms needed to maintain network stability.
Producers therefore provide these forecasts to enable the network operator to ensure the continuity and security of the electricity supply.
How does forecasting reduce risks for the electricity system?
Forecasting is not primarily intended to directly improve the technical performance of power plants. Above all, it reduces uncertainty about the supply/demand balance of the electricity system.
By knowing in advance the volumes injected:
- The grid can anticipate congestion or imbalances.
- Regulatory mechanisms (load shedding, storage, production adjustment) can be activated upstream.
- The risk of grid disruption is greatly reduced.
A practice historically linked to fragile networks
Why is forecasting particularly critical in certain areas?
Production forecasting has historically been widely used in non-interconnected areas, such as France’s overseas departments and territories (Guadeloupe, Martinique, Réunion, etc.).
These territories are not connected to the European mainland grid and have smaller networks that are more sensitive to variations in production. In these contexts:
- A sudden variation in production can destabilise the grid frequency.
- Tenders already include strict forecasting constraints.
Today, with the rise of renewable energies (solar, wind) in mainland France, these issues are also becoming widespread in large networks, which have to manage an increasing diversity of intermittent production sources.
Maturity and prospects of forecasting
What is the current level of maturity of forecasting?
Today, the supply of forecasting is more developed than the demand:
- There are many weather and production forecasting solutions available.
- However, regulatory constraints remain limited.
There is therefore not yet strong pressure on producers to equip themselves, as controls and associated penalties are weak or non-existent.
However, this situation is set to change.
If network operators introduce stricter controls and financial penalties in the event of significant discrepancies between forecasts and reality, demand for Forecast is likely to grow significantly in the coming years.
The forecasting service from S4E SOFTWARE
How does the forecasting service from S4E SOFTWARE work?
The forecasting service is based on:
- Irradiation data provided by Meteonorm, enabling weather forecasts to be obtained from D+1 to D+8, with a time interval of 15 minutes.
- The integration of this data into the production model for each power plant monitored into Energysoft.
The result: an energy production forecast in kWh, specific to each site.
What is the benefit for producers?
Why use Forecast when you are a producer?
Beyond regulatory constraints, Forecast is a valuable decision-making tool. In particular, it allows you to:
- Anticipate the balance between production and consumption.
- Adapt operations according to grid requirements and market prices.
- Decide between injection, power limitation or storage.
On D+1, forecasting enables producers to decide whether to:
- Reduce or shut down certain facilities.
- Smooth out their production.
- Or store energy if expected consumption is low.
Forecasting thus becomes not only a compliance tool, but also a strategic lever for energy management.
