A Must-Read for PV Projects: How to Select the Right Cables for Solar Installations
Driven by the global energy transition and China’s dual carbon goals, the photovoltaic industry has embraced robust growth again in 2026 after a short market adjustment. Utility-scale centralized solar stations as well as numerous distributed rooftop systems for commercial and industrial facilities have made PV projects a popular investment choice once more. Amid the current construction boom, cost control and long-term operational reliability have become top concerns for project owners and EPC contractors. While prices of solar modules are fully transparent nowadays, cables — a seemingly auxiliary product — have become a key area for cost reduction and efficiency improvement.
Today, combining the latest national standards and technological trends of 2025-2026, we will elaborate on the key points of cable selection for photovoltaic projects.
I. PV Special Cables
1. Why Dedicated PV Cables Are Mandatory
Solar modules operate under direct sunlight, with surface temperatures reaching 70-80°C, and moisture often accumulates on the rear side. Ordinary cables will suffer rapid insulation aging and cracking in such harsh conditions, which may lead to electric leakage or even fire hazards within 3 to 5 years. By contrast, professional PV cables are engineered to deliver a service life of over 25 years under continuous outdoor exposure.
2. Core Features & Materials
The insulation and sheath are mainly made of low-smoke zero-halogen flame-retardant polyolefin, processed via radiation cross-linking technology. This treatment restructures the polymer from a linear form into a stable network structure, drastically enhancing the cable’s heat resistance, tear resistance and corrosion resistance.
3. Technical Requirements
3. Technical Requirements
- Environmental adaptability: Qualified products must pass tests for UV resistance, ozone resistance, acid and alkali resistance, as well as damp heat resistance to prevent cracking in extreme weather.
- Voltage rating: The mainstream standard is DC 1.5kV, and the maximum allowable system voltage can reach DC 1.8kV.
II. Aluminum Alloy Cables: A Cost-Effective Mainstream Choice
This is a major highlight of our discussion. Traditionally, copper cables were widely used for DC connections between combiner boxes and inverters, as well as for part of AC circuits in PV systems. Soaring copper prices have pushed the industry to seek alternatives, and aluminum alloy cables have emerged as an ideal solution, with a complete set of mature standards established in 2025-2026.
1. Aluminum Alloy vs. Pure Aluminum
Pure aluminum cables are low in cost but have two critical drawbacks:
- Creep deformation: Loose connections tend to occur over time, resulting in increased contact resistance and excessive heat generation.
- Brittleness: The cables are prone to breakage after repeated bending, bringing inconvenience to installation.
Rare-earth high-speed iron aluminum alloy is manufactured by adding trace rare earth, iron, copper and other elements during smelting. It features excellent anti-creep performance and high flexibility, with mechanical properties close to copper cables, while its weight is only one-third of copper.
2. Key Advantages
- Cost efficiency: For the same current-carrying capacity, aluminum alloy cables cost less than one-third of copper cables. Their light weight also cuts expenses on cable trays and supporting structures.
- High reliability: Though aluminum has slightly lower conductivity than copper, matching current-carrying performance can be achieved by increasing the cable cross-section (about 1.5 times that of copper cables). Safety is fully guaranteed with proper terminal connection using copper-aluminum transition lugs.
3. Updates on National Standards
China is actively promoting the application of aluminum alloy cables in the photovoltaic sector. A new national standard launched in 2025, Rated 1.5kV DC Cables for Photovoltaic Systems - Part 2: Cables with Aluminum Alloy Conductors, has set clear technical specifications for aluminum alloy PV cables.
III. Summary & Recommendations
A solar power station is designed for a service life of 20 to 25 years. Improper cable selection will result in extremely high labor costs for later replacement, far exceeding the cost of the cables themselves.
III. Summary & Recommendations
A solar power station is designed for a service life of 20 to 25 years. Improper cable selection will result in extremely high labor costs for later replacement, far exceeding the cost of the cables themselves.
- DC side (module wiring): Never use ordinary PVC cables. Choose TUV or CQC certified dedicated PV cables (such as PV1-F) to withstand high temperature, high humidity and strong ultraviolet radiation.
- DC transmission lines: Aluminum alloy cables are highly recommended for long-distance power transmission. The mature rare-earth high-speed iron aluminum alloy technology, combined with standard copper-aluminum transition terminals, can greatly reduce procurement costs and lighten the load on cable trays.
- Keep updated with standards: New standards for PV cables have been released intensively from 2025 to 2026. Always verify that the selected products comply with the latest national and industrial standards before purchasing.
Keyforyou Cable specializes in manufacturing dedicated PV cables and aluminum alloy cables. We welcome inquiries from all PV project partners.
Service Hotline
手机
13333333333
Add
East Huiguo Road, Hongsha High-Tech Development Zone, Nanhai District, Foshan City, Guangdong Province, China