Electrical works in solar parks and industry — what you need to know
Electrical works are the heart of a solar park or industrial facility — not just connecting panels and inverters, but engineering, building, testing and commissioning the entire medium- and low-voltage infrastructure to applicable standards.
Why do electrical works determine project quality?
A solar park's yield and safety depend directly on the quality of its electrical works. Poor connections, undersized cables or faulty protection logic create losses, failures and safety hazards that can cost several times more to fix than a quality initial solution.
On industrial sites there is the additional requirement of uninterrupted power and process automation — electrical works must integrate with the existing distribution grid, backup power and control systems. A faulty interconnection can halt production or damage equipment.
What competence do electrical works require?
In Estonia, electrical works must be carried out by a team with the relevant competence and registration. HeilAres holds electrical works MTR registration TEL005181.
Which works belong to the electrical scope of a solar park?
On the DC side: interconnecting panels, routing string cables to the combiner, connecting to the inverter and DC protection. On the AC side: inverter output combiner, transformer connection, medium-voltage interconnection and protection relaying.
Additionally, a control and monitoring system (SCADA) must be built, giving the operator a real-time view of production, faults and maintenance needs. Without it, a solar park is not a fully valuable asset.
How to formalise the electrical works contract?
The contract must specify the scope (DC, AC, medium voltage, monitoring), the applicable standards (EVS-HD, IEC), the test plan and the acceptance protocol. Demand a documented operation and maintenance manual and an initial measurement protocol.
Warranty, maintenance and response-time terms are defined in the project-specific contract.