Regulation by artificial intelligence, the advantage of a partnership to reduce energy consumption in treatment plants

Control by artificial intelligence, the advantage of a partnership to reduce energy consumption in treatment plants

Rennes Métropole has just implemented an experiment at the Laillé wastewater treatment plant in order to limit energy consumption and develop the production of renewable energy. Two photovoltaic trackers have been installed and the treatment plant will be controlled by artificial intelligence.

Background: energy efficiency policies that are already old

As part of the Territorial Climate Air Energy Plan (PCAET — reduction in energy consumption by 40% by 2030 and 60% by 2050), Rennes Métropole is deploying a global strategy aimed at reducing its energy consumption and engaging the territory in a sustainable ecological transition. It concerns, for example, public lighting, for which the actions carried out by Rennes Métropole will have made it possible to reduce the energy consumption of heritage buildings by 40% by 2030 or the thermal renovation of public buildings.

This metropolitan ambition was recently translated into the Gold label (highest distinction), in the European “European Energy Award” program for its policy committed to the energy transition.

The Rennes Métropole sanitation authority contributes significantly to this ambition:

• ISO 14001 certified, environmental management since 2004
• Recognized as an exemplary community in its actions to fight and adapt against global warming as part of its sanitation competence, during the Copenhagen International Water Forum in 2022.

A conclusive experiment

The installation of two 117 m2 photovoltaic trackers carried out by the company OkWind (35) and artificial intelligence proposed by the company Purecontrol (Rennes) is a first in France to supply a treatment plant.

Photovoltaics is now a technology known to everyone. By combining this technology with a system of intelligent and connected trackers, capable of monitoring the sun's radiation in an optimal way, photovoltaic trackers make it possible to obtain optimized renewable energy production all day long.

For its part, Purecontrol has developed an algorithm capable of analyzing the operation of the wastewater treatment plant process in real time. From the data collected, the algorithm will be able to anticipate the actions of the process to optimize energy consumption, the goal, consume better and consume less. This solution has already been tested on 2 wastewater treatment plants in the city and allows a saving of 15 to 20% on the energy bill. It is currently being deployed on all other wastewater treatment plants.

In operation since June, the trackers have so far made it possible to achieve a self-consumption of their production of 68% and an energy autonomy of the station of 30%.

Innovation lies in the combination of these two technical solutions. In fact, the artificial intelligence developed by Purecontrol will make it possible to delay certain consumption during periods when photovoltaic trackers produce the most. Thus, self-consumption will be strengthened and the station's electricity consumption will be further reduced by 12%.

In total, out of an annual consumption of 190,000 kWh (equivalent to 40 households), the device will make it possible to reduce equipment consumption to 108,000 kWh, i.e. a decrease of 43%.