How does electricity work? Lets demystify the life-changing physics.

Date:
Mon, 19 Jun 2023 11:00:00 +0000

Description:
A Tesla coil gives off current electricity, where the negatively charged electrons continuously move, just like they would through an electrical wire. Depositphotos How current is your knowledge? The post How does electricity work? Lets demystify the life-changing physics. appeared first on Popular Science .

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A Tesla coil gives off current electricity, where the negatively charged electrons continuously move, just like they would through an electrical wire. Depositphotos

To the uninitiated, electricity might seem like a sort of hidden magic. It plays by laws of physics we cant necessarily perceive with our eyes.

But most of our lives run on electricity. Anyone who has ever lived through a power outage knows how inconvenient it is. On a broader level, its hard to understate just how vital the flow of electricity is to powering the
functions of modern society .

If I lose electricity, I lose telecommunications. I lose the financial
sector. I lose water treatment. I cant milk the cows. I cant refrigerate
food, says Mark Petri , an electrical grid researcher at Argonne National Laboratory in Illinois.

[Related: How to save electricity this summer ]

Which makes it all the more important to know how electricity works, where it comes from, and how it gets to our homes . How does electricity work?

The universe as we know it is governed by four fundamental forces : the
strong nuclear force (which holds subatomic particles together inside atoms), the weak nuclear force (which guides some types of radioactivity), gravity, and electromagnetism (which governs the intrinsically linked concepts of electricity and magnetism).

One of electromagnetisms key tenets is that the subatomic particles that make up the cosmos can have either a positive or negative charge. To use them as a form of energy, we have to make them flow as electric current. The
electricity we have on Earth is mostly from the movement of negatively
charged electrons.

But it takes more than a charge to keep electrons flowing. The particles dont travel far before they run into an obstacle, such as a neighboring atom. That means electricity needs a material whose atoms have loose electrons, which
can be knocked away to keep the current going. This type of material is known as a conductor . Most metals have conductive qualities, such as the copper that forms a lot of electrical wires.

Other materials, called insulators, have far more tightly bound electrons
that arent easily pushed around. The plastic that coats most wires is an insulator, which is why you dont get a nasty shock when you touch a cord or plug.

Some scientists and engineers think of electricity as a bit like water streaming through a pipe. The volume of water passing through a pipe section at a given time compares to the number of electrons flowing through a particular strand of wire, which scientists measure in amps. The water pressure that helps to push the fluid through is like the electrical voltage. When you multiply amps by volts, you compute the power or the amount of
energy passing through the wire every second, which electricians measure in watts. The wattage of your microwave, then, is approximately the amount of electrical energy it uses per second. How electrons carry voltage through wires

Based on the law of electromagnetism, if a wire is caught in a magnetic field and that magnetic field shifts, it induces an electric current in the wire. This is why most of the worlds electricity is born from generators, which are typically rotating magnetic apparatuses. As a generator spins, it sends electricity shooting through a wire coiled around it.

[Related: The best electric generators for your home ]

Powering a whole city calls for a colossal generator , potentially the size
of a building. But it takes energy to make energy from that generator. In
most fossil fuel and nuclear plants, the fuel source boils water into steam, which causes turbines to spin their respective generators. Hydro and wind generators take advantage of natures own motion, redirecting water or gusts
of wind to do the spinning. Solar panels, meanwhile, work differently because they dont need moving magnets at all. When light strikes a solar cell , it excites the electrons within the atoms of the material, causing them to flow out in a current.

Its easier to transfer energy with lots of volts and fewer amps. As such, long-distance power lines use thousands of volts to carry electricity away from power plants. Thats far too high for most buildings, so power grids rely on substations to lower the voltage for regular outlets and home electronics. North American buildings typically set their voltage to 120 volts; most of
the rest of the world uses between 220 and 240 volts.

Current also doesnt flow one wayinstead, it constantly switches direction
back and forth, which engineers call alternating current. This enables it to travel stretches of up to several thousands of miles. North American wires flip from one current direction to the other 60 times every second. In other parts of the globe, particularly in Europe and Africa, they alternate back
and forth 50 times every second.

That brings the current to your buildings breaker box. But how does that
power actually get to your electronic devices?

[Related: Why you need an uninterruptible power supply ]

To keep a continuous flow of electricity, a system needs a complete circuit. Buildings everywhere are wired with incomplete circuits. A two-hole socket contains one live wire and one neutral wire. When you plug in a lamp, kitchen appliance, or phone charger, youre completing that circuit, allowing electricity to flow from the live wire, through the device, and back through the neutral wire to deliver energy.

Put another way, if you stick a finger into a live socket, youre temporarily completing the circuit with your body (somewhat painfully). An electrician carries out maintenance work on electric wires of a high-voltage power line project on September 28, 2022, in Lianyungang, China. Geng Yuhe / VCG via Getty Images The future of electricity

Not long ago, electricity was still a luxury. In the late 1990s, nearly one-third of the worlds population lived in homes without electrical access . Weve since cut that proportion by more than halfbut nearly a billion people, mainly concentrated in sub-Saharan Africa , still dont have a current .

Historically, almost all electricity started at large power plants and ended at homes and businesses. But the transition to renewable energy is altering that process. On average, solar and wind farms are smaller than hulking coal plants and dams. On rainy and calm days, giant batteries can back them up
with stored power.

What we have been seeing, and what we can expect to see in the future, is a major evolution of the grid, says Petri.

[Related: Why hasnt Henry Fords power grid become a reality? ]

The infrastructure we build around electricity makes a difference, both for the health of the planet and people . In 2020, only 39 percent of the worlds electricity came from clean sources like nuclear and hydro, compared to CO 2 -emitting fossil fuels.

Fortunately, there is plenty of reason for optimism. By some accounts, solar power is now the cheapest energy source in human history, with wind power not far behind . Moreover, a growing number of utility users are installing rooftop solar panels , solar generators , heat pumps , and the like. Peoples homes are not just taking power from the grid, says Petri. Theyre putting power back on the grid. Its a much more complex system.

The laws of electricity dont change depending on where we choose to draw our current from. But the consequences of our decisions on how to use that power do matter.

The post How does electricity work? Lets demystify the life-changing physics. appeared first on Popular Science . Articles may contain affiliate links
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