Power transmission is one of the invisible—but absolutely essential—pillars of the energy transition. In this column, we've covered the operational challenges of power distribution and generation and the bottlenecks in integrating intermittent renewable sources numerous times.
Imagine the electricity sector as a football team, where each of the sources (solar, wind, hydro, biomass and thermal), spread across different parts of the field, with different functions (energy attributes) need to organize and actively interact.
This would be the tactical scheme, some more conservative (hydrothermal), others more daring (renewables). Without a robust and well-coordinated transmission network, this game doesn't develop, and the energy doesn't reach the right audience—or rather, the homes, industries, and cities that need it.
In an energy transition scenario, transmission is crucial, precisely because many solar and wind power plants are located in remote areas, far from major consumer centers.
Transmission therefore allows for the proper integration of these sources and takes this clean energy to where it is needed.
Furthermore, a well-planned and structured network helps to balance supply and demand (making system safety and stability criteria compatible), avoiding blackouts and waste (the so-called curtailment).). This is even more important with intermittent sources like the sun and the wind.
Without transmission capacity, many renewable energy projects are shelved. This is currently a major problem facing our National Health System (SIN).
In Brazil, this issue is especially relevant: approximately 90% of the country is already connected to the National Interconnected System (SIN), one of the largest transmission networks in the world. This places the country in a strategic position to lead a fair, safe, and inclusive energy transition.
The curtailment has its regulatory disposition given by REN ANEEL 1.030/2022, which established three conditions for restricting generation:
- External unavailability, such as bottlenecks caused by the Basic Network and Other Transmission Facilities (DITs);
- Meeting electrical reliability requirements, such as preserving the transmission network; and
- Energy ratio, in the scenario of mismatch between supply and demand of electricity.
In 2025, Brazil's curtailment problem continued to grow, reflecting the mismatch between the accelerated expansion of renewable sources and the electrical infrastructure available to integrate them into the system. According to ePowerBay, more than 129 GWh of solar energy was wasted in January 2025 alone, concentrated in substations such as Janaúba 3 (77,5 GWh), Jaíba (31,9 GWh) and Sol do Sertão (20 GWh) — all in Minas Gerais.
To solve this problem, countries invest in planning and new technologies, primarily aiming for efficiency and loss reduction. Modern, well-planned lines reduce energy losses along the way, making the system more efficient and sustainable.
Speaking of new technologies, two emblematic examples of ultra-high-voltage transmission infrastructure are shaping the global energy transition. In China, networks with UHV (Ultra-High Voltage) technology are now widely implemented within the context of a national "super grid," notably the Changji–Guquan line., which holds the world record: it transmits 12 GW of direct current (UHVDC) power at 1.100 kV, over a distance of 3.293 km.
These lines connect remote, renewable-energy-rich regions (such as the northwest) to major urban centers in the east of the country. The Chinese grid already has 31 UHV lines in operation, combining alternating current (UHVAC) and direct current (UHVDC) technologies, enabling massive integration of renewable sources and significantly reducing transmission losses.
In Germany, the SuedLink Project It is one of the largest underground direct current transmission projects in Europe. At 580 km long and with a capacity of 2 GW, it connects northern Germany (where there is significant wind generation) to the industrialized south, where demand is highest.
It uses ±525 kV HVDC technology with high-capacity copper cables and XLPE insulation, ensuring efficiency and reliability. In addition to reducing losses, SuedLink is essential for integrating more renewable energy into the German grid and meeting climate targets.
Thus, it becomes a little clearer to understand that transmission infrastructure plays a crucial role in the global journey of decarbonization and achieving clean energy goals, whether through increased investment or greater planning in the process of integrating renewable sources.
The opinions and information expressed are the sole responsibility of the author and do not necessarily represent the official position of the author. Canal Solar.
An answer
In rural areas, energy is transferred with just one 110V wire and the neutral is grounded on site.
Can wind energy be transferred with just one wire?