Via Luigi Pirandello, s.n.c. Piano Tavola Belpasso (CT)

Tel: 095 398199 Mail:

09:00 - 18:00

Ita Eng Esp
Services for Photovoltaic Systems

We have an in-depth understanding of all the key O&M (Operations and Maintenance) dynamics for photovoltaic systems, managing over 387 MWp throughout Italy. We specialize in the maintenance of medium and large-scale photovoltaic installations, providing 24/7 monitoring and ensuring a timely response within 3 hours in the event of any fault or technical issue.





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Our integrated services, including the design, construction, and maintenance of photovoltaic systems, are highly flexible to meet the specific needs of each client. You can rely on the Tresun team and our expertise to maximize the performance and profitability of your installations

Engineering Services
  • • Low Voltage (BT), Medium Voltage (MT), and High Voltage (AT) Engineering
  • • Reverse Enginering
  • • CC Engineering and Optimization
  • • Mounting structures and structural stability for ground/roof installations
  • • Security system design
  • • Monitoring system design
  • • Civil works - Static and hydraulic studies
  • • BOS and auxiliary engineering
  • • Consulting services in material procurement and contracting
Specialized Engineering Services

We perform specialized tests directly on-site, using cutting-edge methodologies and technologies, ensuring the same accuracy and quality as laboratories but with a reduction in costs and downtime. We also provide a highly effective interactive diagnostic system. Our know-how and technical structure allow us to carry out large-scale activities on a high number of components.

  • • Verification of serial defects in photovoltaic modules
  • • Verification of anomalies or malfunctions in the system and/or components resulting from incorrect and/or inadequate installation
  • • Verification of component efficiency following extraordinary weather events
  • • Verification of the impact on component efficiency due to mechanical stress from inappropriate disassembly, such as theft"
Engineering Services: REVAMPING

Through Revamping, we modernize, modify, and enhance dated photovoltaic systems. We regenerate some components or the entire system, thus improving performance and energy production

  • • Deterioration and malfunction of parts: Despite a photovoltaic system lasting an average of almost 30 years, some of its parts may deteriorate over time
  • • Outdated design choices: Areas of extreme shading, low solar radiation,

On components, we offer a service that includes:

  • • Integrity
  • • Contact Verification
  • • Thermography
  • • Tightening Verification
  • • Power Cables
  • • Extractors' Operation Verification
  • • Extractors' Replacement
  • • Bolts and Terminals Tightening
  • • Scope of work
  • • Coil Verification
  • • SF6 Switches
  • • Functionality of measuring instruments
  • • UPS Verification
  • • Motor drive system integrity
  • • Temperature control
  • • Grounding efficiency of the Disconnect Switch
  • • Verification of MT/BT Transformers
  • • Protection system verification
  • • Verification and control of MT fuses
  • • Relay integrity of protections
  • • Verification of mechanical interlocks
  • • Verification of auxiliary circuits
  • • Switch integrity and On/Off testing
  • • Cameras and security systems
  • • Alarms and Lighting


Our organization includes the management of all spare parts (modules, inverters, transformers, cables and connectors, hardware), and we also have framework agreements with the main suppliers in the sector, enabling rapid and defined material supplies. We hold training certificates issued by inverter manufacturers to carry out first, second, and third-level interventions on the machines. We take care of the complete management of warranties held by the customer on the components of the system, carrying out on their behalf all the necessary administrative procedures.


The continuous monitoring of performance and the knowledge of each individual plant are the philosophical principles that inspire our Control Room to adopt a proactive and preventive approach to the Operation and Maintenance service.

Specialized technicians continuously monitor the plants 24/7 throughout the year to anticipate malfunctions and manage on-site technician interventions, tracking every activity from the initial assessment to its resolution. Each technician is responsible for a portfolio of plants, overseeing monitoring with active multi-day checks on all major components (Inverters, String Boxes, Meters).


We are authorized to manage surveillance services on behalf of third parties, collaborating with a leading security institute specialized in providing security services for photovoltaic fields. Each plant is constantly monitored, and in the event of an alarm, the intervention procedure is activated, in line with the client's needs and in full compliance with the requirements of insurance companies.

  • • Full service 24/24
  • • On-site assistance and video surveillance managed by a central Control Room
  • • Flying intervention teams in collaboration with local law enforcement
  • • Continuous monitoring of the performance of security systems with reporting service and access control.


Cleaning with a mechanical system that avoids contact with the panel to exclude any risk of abrasion.


We prevent shading phenomena through operations such as rotary mowing, shredding, grass collection, edge cutting, and hedge pruning.

EPC - Engineering, Procurement and Construction
What is an EPC Contractor?

The acronym EPC stands for Engineering, Procurement, and Construction, and in the field of photovoltaics, it refers to the entity responsible for everything related to the design (Engineering), procurement (Procurement), and construction (Construction) phases of a photovoltaic plant, as well as its maintenance and delivery. In other words, the EPC Contractor in photovoltaics is the entity responsible for delivering a turnkey photovoltaic plant.

Advantages of turning to an EPC Contractor

Turning to an EPC Contractor in the photovoltaic sector can bring numerous advantages. Firstly, the EPC Contractor is a specialized and qualified entity capable of managing and ensuring the execution of workmanship, providing greater security and reliability in the installation of the plant. Additionally, with its experience and expertise, the EPC Contractor can oversee the entire project from start to finish, simplifying the work for the contracting company and allowing all aspects of the work to be included in a single contract for easier monitoring. Finally, the EPC Contractor can guarantee adherence to established timelines and costs, providing greater transparency and clarity regarding the investment to be made..

The tasks of the EPC:
  • • Analysis of customer needs and assessment of the most appropriate solutions for the installation of the photovoltaic system;
  • • Design of the photovoltaic system, including the specification of photovoltaic modules, inverters, and other components necessary for the installation;
  • • Procurement of materials needed for the implementation of the photovoltaic system, including modules, inverters, accessory components, and support structures;
  • • Construction of the photovoltaic system, including the installation of modules, inverters, and other components, as well as connection to the electrical grid;
  • • Verification of the operation of the photovoltaic system and training of personnel responsible for the management and maintenance of the system;
  • • Provision of after-sales assistance, with the ability to intervene in case of faults or malfunctions of the photovoltaic system.

Through Revamping, we modernize, modify, and improve dated photovoltaic systems. We regenerate some components or the entire system, thereby enhancing performance and energy production.


The photovoltaic system, despite having an average lifespan of almost 30 years, may experience issues of deterioration and malfunction in some parts, caused by poor quality materials, weather conditions, and unforeseen breakages. Additionally, outdated design choices can negatively impact the proper functioning of the system, such as areas with extreme shading, low solar radiation, or poor exposure. Furthermore, the continuous evolution of the photovoltaic industry leads to the obsolescence of certain elements that are no longer compliant, necessitating their modernization to ensure the proper functioning of the system. However, with proper maintenance and the update of obsolete parts, it is possible to ensure a long life and high efficiency for the photovoltaic system.

What is Revamping?

The revamping of photovoltaic plants is a process that involves a series of interventions that go beyond the simple regeneration of solar panels. In fact, the Operator classifies interventions as "significant" and "non-significant." "Significant" interventions include the replacement, removal, and new installation of main components such as photovoltaic modules and inverters, partial movement of modules, modification of the grid connection regime, and changes to the identification code of the connection point to the grid. However, these interventions cannot increase the nominal power of the plant by more than 5% for systems with power up to 20 kW or more than 1% for those with power exceeding 20 kW.

The interventions

The "significant" interventions include the replacement, removal, and new installation of the main components, namely the modules and inverters, partial movement of the modules, modification of the power supply regime to the grid, or a change in the identification code of the connection point to the grid. The "non-significant" interventions, on the other hand, involve moving inverters and minor electrical components, replacing minor electrical parts such as wiring, and interventions on support structures, such as roofs or truss structures that house photovoltaic modules.


Photovoltaic revamping can be justified in many different cases. In addition to the natural decline in the performance of the modules, there may be initial design problems to correct, as well as the need to comply with increasingly stringent plant safety standards. Furthermore, the importance of revamping is now linked to the need to digitize assets, creating a unique performance monitoring platform that integrates energy consumption and production data. This also allows for active and remote management of the asset in terms of preventive maintenance. Thanks to improved post-intervention production, the return on investment can occur in a short period, typically around 2 or 3 years. Revamping represents another step towards achieving the goals of the European "Green Deal," the socio-economic program defined by the Union to make the Old Continent's economy more sustainable without further land occupation.


Repowering involves, without acting on the entire plant, interventions for the energy enhancement of the system and modification of its components.

Necessary Interventions

The first and main advantage of repowering is the increased productivity of the renewable energy production plant, translating into a return on investment in economic terms. However, repowering is particularly important because it addresses one of the main challenges of renewables, namely the scarcity of new sites suitable for hosting new plants, especially in a densely populated country like Italy. Repowering overcomes this difficulty, allowing for a more effective achievement of decarbonization goals by 2030. According to Agici, the modernization of renewable plants would enable Italy to achieve nearly half of the renewable goals outlined in the PNIEC by 2030, without consuming new land

What does it consist of

Repowering is an intervention that involves the partial or total upgrade of modules, inverters, and electrical connections, with the aim of increasing the nominal power and annual production of a plant. Thanks to the technological evolution of solar panels, whose average efficiency has increased from 14% in 2006 to almost 20% currently (source AGICI), photovoltaic repowering is a very effective solution. By replacing old panels with the latest generation ones, solar production in Italy could be increased by over 40% without the need for additional land occupation.

The monitoring

The installation of a software-based management and monitoring system is a significant addition during the repowering process of a photovoltaic system. This type of system is often absent in older and less sophisticated photovoltaic systems but allows for constant and accurate monitoring of energy production, detection of malfunctions, and immediate notification of any faults. It also offers a wide range of functionalities, such as monitoring the temperature of photovoltaic modules, solar irradiance, and the output voltage of the inverter. This information enables important decisions regarding preventive maintenance of the system and checking the condition of cables and connections. It helps optimize the efficiency of the system, prevent malfunctions and faults, reduce operational costs, and maximize energy production



team commerciale


Handles comprehensive management of the relationship with the client, investor, or partner, providing necessary assistance throughout the entire partnership.

team marketing


Handles presenting the values and features of the product and service clearly to clients or partners, meeting the objectives of individuals and organizations.

team tecnico


It follows the technical aspects of the project and maintenance from the beginning to the conformity verification, collaborating with the departments of commerce, development, purchasing, and logistics and relying on qualified internal and external designers and technicians.

team O&M


Provides assistance and excellent O&M throughout the plant's lifespan with a team of highly specialized maintenance professionals in 1st, 2nd, and 3rd-level inverters, and extensive expertise in medium voltage (MT). We offer constant support through an active 24/7 monitoring room.

team logistica


The logistics team handles the management of spare parts and warehouse inventories. They select various components and spare parts from certified manufacturers and suppliers, working with top-tier shippers to ensure the best balance between quality, reliability, and costs.