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The problem with electricity -

One of the biggest questions when it comes to electricity is how best to transport it over long distances. After all, it is not only people living close to power plants who need electricity in their homes.

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Enter: UHV -

Ultra-high voltage (UHV) transmission is one answer to this question. Essentially, UHV involves the bulk movement of electricity over long distances at a very high voltage.

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How it works -

UHV works on the basis that a higher voltage during transmission means lower electric currents for the same amount of power transmitted.

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How it works -

Having lower currents, in turn, means that there is less heat loss as the electricity moves through the transmission lines, and the power therefore moves with greater efficiency.

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Popular solution -

UHV is not the only way to transmit electricity, but it has become the go-to solution for many countries and there is an increasing investment in UHV infrastructure.

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China leading the way -

The country leading the way when it comes to UHV transmission lines is China. Indeed, the Chinese refer to them as "bullet trains for power."

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In the early days -

As early as 2006, the development of UHV became part of Beijing's five-year plan. This is a good indication that, even at this early stage, UHV was already part of the national strategy.

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The Xiangjiaba-Shanghai link -

China's first UHV transmission link went into service in 2010, and connects the Fengxian Converter Station, which sits just outside Shanghai, with the Xiangjiaba Hydropower Station in southwest China.

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Powering Shanghai -

The Xiangjiaba Hydropower Station harnesses the energy of the Yangtze River and then sends it to the Fengxian Converter Station, where it powers the buildings of Shanghai.

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Important power source -

With almost 4,000 pylons and cables that cross gorges, rivers, and fields, the Xiangjiaba-Shanghai line meets up to 40% of Shanghai's demand for power.

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The beginning of an era -

The introduction of the Xiangjiaba-Shanghai transmission link in 2010 marked the beginning of an era that would see UHV infrastructure springing up all over China.

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Energy sources -

Until recently, however, the infrastructure has mainly been used to send electricity generated by hydro and coal from remote regions to more populous areas of the country.

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New focus -

Nowadays, the focus is on using these huge power cables to transmit electricity produced using renewable electricity sources, such as solar and wind.

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2022 commitments -

In 2022, the country's National Energy Administration said that wind and solar bases in the desert should focus on building UHV transmission lines to share their power with far-flung parts of the country.

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Starting construction -

In 2023, construction began on the first such line, which will link the Ningxia Autonomous Region in the northwest with the southern province of Hunan.

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UHV in other countries -

Although China is the trailblazer when it comes to UHV infrastructure, there are also other countries that have started putting their own plans in place.

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Brazil -

In Brazil, for example, there are already two UHV transmission lines in operation. They transmit hydropower from the Amazon basin to more populous regions in the southeast, such as São Paulo and Rio de Janeiro.

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Brazil -

Both the operating UHV transmission lines in Brazil were built by China's State Grid, and there are currently plans underway for them to build a third.

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India -

India, too, has had the Green Energy Corridor Scheme in place since 2015. This is a scheme that includes dedicated transmission lines for renewable energy.

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India -

Indeed, India has certain states that are rich in those resources, such as Andhra Pradesh in the south and Gujarat in the west.

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Cross-continental UHV -

There are even plans in some parts of the world to build UHV transmission lines that cross continental borders.

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Underwater transmission -

In Europe, for example, cables are being put in place underwater that would be able to transmit solar and wind power from North Africa.

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Challenges -

Building cross-continental UHV transmissions networks is not so simple, however. Even if the technology is ready to go, there are inevitably other challenges.

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Regulations -

One of the main hurdles to clear is regulatory problems. There is always a huge amount of paperwork involved, and sometimes it can be difficult to get local residents on side.

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Cost -

Another challenge with UHV transmission is cost. For a project to go ahead, the stakeholders must agree to share the cost, and this can be a difficult situation to achieve.

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The situation in the US -

According to Wang Xuan, who is an advisor on clean energy strategies at the Regulatory Assistance Project, this is why UHV hasn't taken off yet in the US.

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Mass blackouts -

The final challenge with mega grids is that there is a higher chance of a mass blackout in the event that one part of the network fails.

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Bigger system, bigger risk -

Experts are acutely aware that the larger the system becomes, the more safeguards will be needed to prevent a mass blackout from occurring.

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Combination solution -

It seems likely, then, that the renewable energy solution of the future will use a combination of UHV infrastructure and more localized energy supplies, such as mini grids.

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Final thoughts -

On their own, neither solution is perfect. Working together, however, they may pave the way for a sustainable energy future.

Sources: (BBC)

See also: The Opium Wars that devastated China

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