The first Hybrid Power Station in operation in Tilos island at Energypress – Renewable & Storage Forum

Mr. Zisimos Mantas, Chief Business Development Officer (CBDO) of the EUNICE ENERGY GROUP (EEG) and member of the Board of Directors of the Hellenic Wind Energy Association HWEA/ELETAEN, speaking on “Storage οn the Islands – Hybrid Systems” presented the measurable results and innovative storage technologies of the pioneering and internationally recognized hybrid system on Tilos at Energypress forum entitled “Renewable & Storage – new environment, new markets, new actors in the era of energy transition”. The Forum took place at the Wyndham Grand Athens Hotel in Athens on Thursday, 24 October.

Mr. Mantas began his speech by saying that the EEG, a pioneer, innovator and investor in green energy, recently completed a large investment process increasing now its capacity by 21MW to 80.6MW total of installed wind farms and to 6.7MW of photovoltaic power plants, since a large investment project was completed about a month ago. Looking ahead, the EEG Group is keen on developing new projects for the hybrid, wind and photovoltaic power plants.
At the same time, the company expands its business into marketing and electricity trading, supports developing energy communities in the country, develops the EV charging network in Europe by starting from Greece, in collaboration with Blink Charging Co., as well as produces small wind turbines at the privately owned factory in Mandra Attica and in-house Smart Home Devices.

He also noted that the first Hybrid Station in operation on the island of Tilos is a starting as well as a reference point for all new investments of the Group, which are self-funded, whereas the project is a milestone for Greece while taking European dimensions.

The main points of Mr. Manta’s presentation are summarized below:

“Regarding Tilos Hybrid Station, we are pleased to announce that the station has been operating successfully for one year. It is compatible with the Greek and European Storage Operating Frameworks but also with the Greek and Non-Interconnected Islands Code with regard to Hybrid Stations.

The presentation included some typical examples of the station’s capabilities and how it can respond to the electricity grids of our non-interconnected islands.

Tilos Hybrid Station has received a lot of positive comments from the European Commission and international construction certification firms, as, the letters also show, it has successfully operated and achieved its goal, which is to demonstrate electricity generation and storage by making it now fully manageable and distributable by the operator.

Technical characteristics of the Hybrid System


Tilos Hybrid Station consists of batteries. It is an innovative, model technology consisting of nickel-chloride batteries with a rated power of 800kW and with a rated capacity of 2.800MWh.

Wind turbine:

The wind station is nothing less than a wind turbine with features such as variable speed, power control by variable turbine vane keying angle & uninterrupted power supply in network fault state (FRT capability).

Photovoltaic Station:

The 160kW rated PV Park consists of 8 inverters of 20kW each with full control over each of them. Battery inverters can operate in various operating modes such as P-Q as well as U-f. At the same time, they have full control in a very short time and can configure grid conditions in case there is no grid. Overall the guaranteed power of the Hybrid Station is 400kW which is fully available and distributed by the administrator according to the sophisticated control and communication system developed by EEG and has been operating for a year.

Control & Management Systems:

For the Hybrid Station’s monitoring and control unit to be able to operate the system, it must have daily and per-second contact with the operating platform of the non-interconnected island administrator.

In this context, and for the successful completion of the project, EEG has already set up the daily electricity market platform in which the Hybrid Station (HBS) also participates with offers on the daily market until 12 noon of the previous day.

At the same time, we have installed and operate a wind and solar power forecasting platform that helps us make decisions about how we can participate in the day-to-day market but we have also designed, manufactured and operated the production reporting system to the administrator, where the latter approves or rejects this statement accordingly.

Finally, the HBS operation, supervision and control system are integrated with its real-time distribution platform with complete interconnection and synchronization with the administrator’s servers to control and certify the generated energy.


The system developed by the manufacturer first incorporates sophisticated algorithms to produce each of its subsystems which prioritize Renewable Energy Sources supported by battery operation.

In situations where Renewables for some reason momentarily lose their output, automatically the batteries enter into the system and perform without losing distribution, fully satisfying the setpoint originally prescribed by the administrator.

The Hybrid Station can satisfy voltage support conditions at the level of a second and at shorter intervals as well as being able to support the network frequency by injecting nominal active power during these periods.

The last two functions are the auxiliary services that the station already provides to the system from the highly sophisticated control system implemented.


Innovative technology & advantages

With the technology we have developed and operate in the Tilos project, it is clear that stochastic and intermittent RES can be made through storage and control systems, fully distributable and controllable. In this way, we achieve increased penetration of RES in non-interconnected islands by avoiding the consumption of conventional fuel and emission of corresponding gaseous pollutants but the main asset is that now the wind turbines and photovoltaics can become basic units, fully compatible and controllable by the Administrator, who can ultimately distribute their energy throughout the day.


Institutional and regulatory issues that concern the operation of such systems to be resolved

Significant steps need to be taken immediately with regard to creating a market in our country alongside the electricity market; this will be the market of auxiliary services in which batteries – storage systems as a whole can have a significant source of revenue.

At the same time, an integrated hybrid power station system is pending in line with the requirements of the European Directive on renewable energy and, as the Government has announced, a simplification of the licensing process is expected as many applications to the Regulator and the Administrator are still under process.