More than 100 energy-industry specialists attended ENERGY STORAGE OPEN DAY 2026, an event organised by FomCo Solar and Dunext Romania that combined a technical conference in Târgu Mureș with an applied visit to the hybrid energy project in Chirileu.
Participants included investors, developers, EPC contractors, designers, integrators, operators and service specialists, together with Dunext teams from five countries and the management team of FomCo Solar. The project presented at the event integrates a 6 MWp solar power plant, 5 MW of power conversion capacity and 20 MWh of energy storage, comprising four 5 MWh Dunext PowerMount containers and two PCS containers.
A rare case: the same partner sees the project from three perspectives
The learning value of the Chirileu project is amplified by FomCo Solar’s unusual position. The company is simultaneously the investor and beneficiary of the investment, the EPC contractor that designed and built the project, and the team responsible for its long-term operation and maintenance.
This combination enables a complete assessment of the decisions involved: what justifies the investment, how the solution should be sized, where integration risks arise, what must be prepared for commissioning, and how the initial choices influence operating costs, availability and asset performance throughout its lifetime.
| “We can discuss this project from three perspectives that are usually held by different companies. As an investor, we focus on returns and risk. As the EPC contractor, we are responsible for integration quality and the execution schedule. As the O&M operator, we will live every day with all the decisions made during design and construction. This is precisely why the lessons from Chirileu are relevant to the entire industry, not only to a single project.” — Nyulas Bernát László, founder of FomCo Solar |
Why storage changes the economics of a solar power plant
A solar power plant generates the most electricity around midday, precisely when many other solar assets are injecting power at the same time. Without storage, the energy must be sold immediately, leaving the producer exposed to hourly price differences, grid constraints and costs generated by deviations from the forecast.
The Chirileu system has a nominal duration of four hours at its maximum power of 5 MW. It can absorb energy during periods of high production and deliver it later, when demand and the value of electricity are higher. In this way, a variable asset becomes more controllable and easier to integrate into both the market and the grid.
In a properly sized and operated model, the battery can create value from several sources:
- Energy arbitrage: shifting electricity from low-price hours to higher-price periods.
- Imbalance reduction: aligning production more closely with the notified schedule and lowering deviation costs.
- Balancing and reserve services: responding rapidly to system needs, subject to the applicable technical and commercial qualification.
- Avoiding curtailment: storing part of the energy that might otherwise be reduced during periods of congestion or overproduction.
- Better use of the grid connection: using the same connection infrastructure with a more controlled output profile.
Stacking these value streams can significantly shorten the payback period compared with a model based exclusively on the immediate sale of solar generation. There is, however, no universal payback period: the result depends on hourly price spreads, access to balancing markets, the cycling strategy, battery degradation, financing, operating costs and the quality of the EMS that optimises operation.
Benefits for the grid and end consumers
For the grid, storage provides flexibility. A battery can rapidly absorb surplus electricity and inject power when needed, helping reduce peaks, manage congestion and limit the loss of renewable generation through curtailment. The fast response of BESS also makes these systems suitable for services that support system frequency and stability, where the configuration and market rules allow.
For consumers, the benefit appears at system level: more solar energy can be used after sunset, the need to dispatch more expensive generation during peak hours can decline, and dependence on imports and exposure to extreme-price episodes can be reduced. Storage does not automatically guarantee an immediate reduction in every bill, but it contributes to a more efficient, stable and less volatile energy system.
Why investment in storage makes sense now in Romania
Romania is entering a stage in which the expansion of renewable generation must be accompanied by flexibility. Romania’s National Energy and Climate Plan sets a target of 1,200 MW of battery storage capacity by 2030, while the Ministry of Energy has launched support programmes dedicated to investment in batteries. At the same time, technology costs have fallen rapidly worldwide, and balancing markets are becoming increasingly important for the secure operation of systems with a high share of solar and wind generation.
For entrepreneurs, the opportunity extends beyond funding. Companies developing projects now can secure grid-connection capacity, accumulate operating data, build teams and partnerships, and learn to operate an asset that participates in several markets. This experience advantage is difficult to recover later.
A learning project for investors, EPC contractors and O&M operators
ENERGY STORAGE OPEN DAY 2026 was designed as an applied exchange of experience, not simply as an equipment presentation. The lessons from the project can be used by three categories that are essential to the maturation of the market:
- Investors can analyse the business model, revenue structure, market risks, financing, warranties and the investment payback strategy.
- EPC contractors can learn from the integration of PV, PCS, batteries, EMS, protection systems and the grid, as well as from the preparation of testing and commissioning.
- O&M operators can assess monitoring, thermal management, safety, preventive maintenance, spare parts, warranties and cycle optimisation.
For the community of Chirileu and Mureș County, the project brings more than electricity injected into the grid: it provides visibility, technical expertise, operation and maintenance activity, opportunities for local suppliers, and a tangible example that advanced energy infrastructure can be developed and operated in Romania.
| “At Chirileu, we showed that value does not lie only in the number of installed megawatt-hours, but in the project’s entire chain: sizing, integration, control, commissioning, operation and service. A well-built system can balance photovoltaic generation, combine several revenue streams and accelerate investment payback. The Dunext Romania team supports investors, EPC contractors and every partner involved, from developing the optimal solution to commissioning, service, optimisation and scaling.” — Marius Varga, Country Manager, Dunext Romania and the Republic of Moldova |
Dunext Romania: local support throughout the project lifecycle
Dunext Romania is part of the international Dunext group, which develops and manufactures energy storage solutions for commercial, industrial and utility-scale applications. The local team works directly with investors, developers, EPC contractors and project operators, from analysing the production profile and defining the optimal architecture to commercial proposals, integration, commissioning, training, service and subsequent capacity expansion.
A local presence enables shorter response times, direct communication and continuity between the commercial phase, implementation and long-term operation — essential elements for BESS projects, where technical performance and financial results depend on how the entire system is designed and operated.
About FomCo Solar
FomCo Solar is a Romanian company specialising in the design, implementation and maintenance of photovoltaic systems and energy storage solutions. In the Chirileu project, the company has a threefold role: investor and beneficiary, EPC contractor and O&M operator, giving it a complete perspective on the investment lifecycle.