Research and innovation supporting the storage of renewable energies

Discover all the chapters of our feature on Research and Innovation

Renewable energy can only become mainstream if we can find efficient ways to store it for use on days when the wind does not blow and the sun does not shine. Storage is also used for much shorter periods to balance the uneven energy generated by natural sources – a cloud passing by, or the wind changing speed or direction. Experts call this “intermittency”. Storage solutions can thus increase the quality and reliability of electricity for every day and critical uses, and as storage becomes cheaper, it becomes more profitable to use renewable energy.

New renewable energy storage technologies

Researchers in the ENGIE “Energy Storage” lab focus on technologies and solutions to make energy storage competitive, eco-friendly and adapted to large industries. We are always on the lookout for new technologies that are both practical and profitable. For several years our focus has been on lithium-ion (Li-ion) batteries and their application to ENGIE and its customers’ use cases. Our work has allowed us to understand the electrochemical functioning of this technology family and its multiple variations, their limitations, ageing mechanisms, their fire and explosion risks. Through this understanding we can provide guidelines to select the best Li-ion battery for each use case and operate the batteries for storage applications, thereby contributing to the success of commercial projects.

We have launched a research roadmap on redox-flow batteries (RFB), a new, less mature and completely different technology family that promises many advantages like a lower levelised cost of storage, the absence of fire and explosion risks, a longer life time without performance degradation due to ageing, and a better fit with use cases requiring several hours of storage capacity, like renewable energy shifting. We performed a comparative study of many RFB technologies and companies (mostly startups) developing them. The most promising ones have already been tested in our laboratory facilities, and are preparing first industrial pilot projects in 2021.

A revolutionary platform to manage a 100% renewable mix

ENGIE EPS is a startup acquired by ENGIE in 2017, which has since become the technological division of ENGIE focusing on energy storage systems, microgrids and eMobility, enabling the paradigm shift in the global energy system towards renewable sources and decentralized energy production. With a unique team of engineers (over 100 people, 15 nationalities, a third with either a PhD or MBA), it has filed 130 patents in 33 countries, and over 500 industrial secrets. ENGIE EPS products are fully developed on the HyESS platform, a revolutionary proprietary technology that allows integrating every renewable source with all energy storageformulas, including electric vehicles. The company has installed storage systems and microgrids in 23 countries and is set to install the largest and fully renewable island electrification systems in the World.

Lifou, bringing green energy storage to life

Since 2017, ENGIE has been implementing a project to generate clean energy that is then stored on the island of Lifou in New Caledonia with the aim of replacing the diesel generators at the island’s thermal power plant. Solar and wind power generate energy, and a large-scale storage unit, driven by an innovative energy management system, went into its second phase in 2019. The system supplies Lifou with 100 percent green energy for several hours per day and stores excess energy which is then returned to the grid when needed, thus reducing diesel consumption. ENGIE believes that Lifou, once its energy needs are met with 100 percent renewable sources, will be a global model for green energy.