The Electrical Grid

Podcast Transcript

The modern world runs on electricity. That isn’t a throwaway statement. If we remove electricity, our civilization will quickly fall apart.

The power that runs the modern world is dependent on a very technical, and in some cases very fragile, network of electrical generation, transmission, and consumption.

These electrical networks can be as small as a city or as large as a continent.

Learn more about the electrical grid, how it works and how may change in the future on this episode of Everything Everywhere Daily.

I cannot stress enough how important electricity is to the modern world. In fact, I think you could say without any exaggeration that electricity is the modern world.

Everything you can think of that is part of modern civilization, from light to heat to water to transportation to food is all dependent on electricity.

Even things you might think aren’t directly connected to the grid eventually are dependent on electricity. Internal combustion engine cars aren’t connected to the grid, but the ability to get fuel is dependent on pumps that run on electricity.

Water might run when the power goes out, but that will only last until water tanks and water towers are depleted. For the water to continue to flow, you need electricity.

Most of us have experienced the power going out, but only briefly. If you have been unlucky, you might have suffered through a few days, or in extreme cases if you’ve been in an area hit by a natural disaster, maybe a few weeks.

But even in those cases, affected areas are able to be supported by surrounding areas that have power.

If all the world’s electricity were to go away tomorrow, it would be the single largest disaster in terms of loss of life in world history.

So with that, the topic of the electrical grid is extremely important.

The grid is simply a complex network designed to deliver electricity from producers to consumers.

That’s easy to say, but a lot goes into it, and a host of things need to be considered.

Let’s start with electrical production. Electricity begins at generation plants where energy sources, like coal, natural gas, nuclear power, solar, wind, or hydroelectric power, are converted into electrical energy.

Each type of plant generates electricity differently, but ultimately, they all convert different forms of energy into electrical energy, which is then sent out on the grid.

This episode isn’t about the pros and cons of various forms of electrical generation. I’ve touched on some of them in previous episodes. However, from a grid standpoint, there is something that is absolutely vital which needs to be considered.

For the most part, electricity on the grid can’t be stored. It has to be consumed as it is produced.

Many overlook this because electrical storage is very common for smaller applications. Batteries can power devices, automobiles, and, in some cases, entire buildings.

The other important fact is that electrical demand varies throughout the day and even throughout the year.

So, while there are some exceptions, more on that in a bit, electricity has to be produced as it is being consumed and it must change throughout the day.

Sources like wind and solar are clean and do not use any fuel. However, their production is inconsistent. Their power generation is dependent on the weather and the time of day. At certain times during the year they may produce enough to cover the demand for the entire grid, and during other times, they may produce next to nothing.

Other sources of electrical generation can provide a steady base load of electrical generation at all times. Nuclear, hydro, and geothermal are very good at this, but they cannot easily adjust their output.

There are some new models of proposed nuclear power plants that would be able to adjust their electrical output faster, but those are still on the drawing board.

Coal and especially natural gas can adjust their output quickly. All that is required is to burn more or less fuel.

Now, some of you might be thinking that you’ve heard news stories of projects that were designed to store power for the grid so it could be used later.

These projects do exist, but they are few and far between, and there just aren’t many of them. There have been systems built that pump water into a reservoir at a high level and then release it when power is needed to run turbines.

There are also some grid-scale batteries that have been deployed, but at best, they can only offer power for a few hours or even seconds, depending on how much of the grid they are providing power to.

Once electricity is created, it has to be delivered to consumers. The transmission of electricity is an important part of the grid that is often overlooked.

The transmission network consists of high-voltage power lines. Electricity at this stage is often at extremely high voltages, often exceeding 100,000 volts, sometimes well beyond 100,000 volts, to reduce energy loss as heat during transmission over long distances.

Electricity transmitted over long distances loses energy primarily due to the resistance of the wires through which it flows. This loss of energy manifests as heat and is proportional to the square of the current flowing through the wire.

By increasing the voltage and consequently reducing the current, the power loss due to the wires’ resistance is significantly reduced. This is critical over long distances, where even small losses per unit length can accumulate to substantial amounts.

The transmission of electricity is the holy grail of superconductors. If a stable, high-temperature superconductor could be made at a relatively low cost, it could result in lossless electrical transmission.

On average, losses from electrical transmission range from about 5% to 8% but can be higher in less efficient or older systems.

This energy loss also puts limits on just how far electricity can be transmitted. I’ve read proposals about the creation of a global electrical grid and how energy could be routed anywhere on Earth, just like data.

However, these ideas aren’t really possible given our current technology. The cost of such a system, coupled with the power losses of delivering electricity over extreme distances, make it unfeasible.

Alternating current is the most commonly used method for transmitting electricity in high-voltage power lines. This is primarily because AC can easily be transformed to higher or lower voltages using transformers, which is crucial for efficient power transmission over long distances.

The electricity in your home does not come in at such high voltages. Before it does reach the final destination, the voltage has to be lowered.

Electricity travels to substations, where transformers reduce the voltage to a lower level suitable for distribution. Substations are pivotal nodes in the grid, serving as hubs where the transmission network connects with the local distribution networks. They manage the flow of electricity and maintain the grid’s reliability and security.

At substations, step-down transformers reduce the voltage from the transmission level to a lower distribution level, typically between 13,000 and 69,000 volts.

From the substation, the reduced voltage electricity is still too high for a normal building. It is moved on wires, the likes of which you probably see every day.

Not all electrical wires are above ground. Sometimes, they are buried.

Many people, including myself, have often wondered why all electrical lines aren’t buried. It’s a reasonable question.

Electrical lines can be unsightly, and they are easily susceptible to a host of accidents and the environment.

There actually are good reasons why all electrical lines aren’t buried underground.

For starters, burying power lines is significantly more expensive than using overhead lines. Depending on the location and soil conditions, the costs can be up to 10 times higher. This is why the most common place underground wires are installed is in new developments.

When power lines are buried, detecting and repairing faults becomes more challenging and time-consuming. With overhead lines, a visual inspection can often locate a problem quickly.

Underground cables tend to get hotter than overhead lines because the surrounding soil insulates them and prevents heat from dissipating quickly. This can reduce the efficiency of power transmission and requires cables to be specially designed to handle higher temperatures.

Because of this, while overhead lines are exposed to weather and environmental conditions, they generally have a longer lifespan and require less replacement over time compared to buried cables, which may suffer from degradation due to soil conditions or other underground risks.

Closer to the point of use, such as in residential areas, the voltage is further reduced to make it safe for home use. This happens through smaller transformers, often seen on utility poles. These transformers step the voltage down to the final voltage, typically 120 or 240 volts, which is suitable for residential use.

The connection of all of these elements constitutes what is generically called the grid. However, it would be more accurate to say that there are grids, plural.

The Earth is covered in a series of grids, some of which are large and some not quite so large. They seldom correspond perfectly to national borders. Some large countries have multiple grids and many grids cross international borders.

North America, for example, has two major grids and three minor grids.

The Eastern Interconnection is one of the two major power grids in North America. It serves most of the eastern United States and Canada, extending from the Atlantic coast to just west of the Rocky Mountains.

The Western Interconnection is the other major power grid in North America. It serves the western United States, parts of British Columbia in Canada, and small portions of Mexico. It operates largely independently of the Eastern Interconnection.

The minor grids operate mostly in Texas, Quebec, and Alaska.

Europe has one major grid that covers almost all of mainland Europe, including Turkey and some of North Africa. There are minor grids for the island of Great Britain, Ireland, and grids shared by the Nordic countries and one for the three Baltic states.

Likewise, South America has four, and China has two. Australia has a major grid connecting everything on the east coast and Tasmania and some minor grids in the west and north.

Russia has one giant one that also covers former Soviet republics in Central Asia and the Caucuses.

Africa has a large grid in the south, two in the north, and one major one in West Africa.

As important as the electrical grid is to the modern world, there are concerns about the future.

Most people don’t think about the electrical grid, because so long as it works, they don’t think anything is wrong.

Yet, there is a lot of aging infrastructure in electrical grids all over the world. The grid was built piecemeal in many places, not all at once.

This infrastructure, much of which is 40 to 50 years old, will have to be replaced That is going to require a massive investment, which will be significantly larger than the initial investment to construct it.

…and it isn’t just that the infrastructure is aging.

Over the last several decades consumption of electricity in the developing world has been rather stable. Any increases in consumption have been offset by improvements in efficiency.

However, the world is looking at two things that might increase electrical consumption significantly: electric vehicles and artificial intelligence.

Both of these things represent significant increases in electricity consumption above and beyond current consumption. To meet the demands of these new technologies, it will require significantly more electrical generation, as well as investments in infrastructure.

Many proposals have been made to modernize the grid. One suggestion has been to improve technology to make the grid smarter. This would involve moving electricity to where it can be used most efficiently.

Another suggestion is linking many of the bordering major and minor grids that currently exist. In North America this would mean possibly linking the eastern and western grids and possibly joining Texas and Quebec as well.

In Europe, it would be linking Ireland, Britain, and the Nordic countries with the mainland Europe grid.

Another major concern is the security of the grid. Because of the importance of the grid to the functioning of society, it is a major security threat. Hardening the grid from cyber attacks is a top priority for any future grid investments.

Most people never think about the electrical grid because so long as the lights turn on, they are happy. It is only when the lights go off that people give it much thought.

Yet, the electrical grid is a critical infrastructure system that requires meticulous planning, management, and technology to ensure that electricity is always available where and when it is needed.