Texas Renewable Energy Policy Sets an Example for the World

China, the EU, and other regions also are decreasing their fossil-fuel dependence

3 min read
Image of the state of Texas made of different shades of green circles.
Image licensed by Ingram Publishing

THE INSTITUTEIn many areas of the world, renewable energy is now a cheaper source of electricity than fossil fuels. It is possible that renewable energy soon will be the preferred choice all over the world.

Transition to renewables is no longer a question. The potential exists that renewable energy and its storage technologies will be able to generate 100 percent of the world’s energy in less than 30 years. The switch to renewable energy would reduce the cost of electricity to, on average, from US 80 cents to 60 cents per megawatt-hour globally, according to recent research by Lappeenranta-Lahti University of Technology, in Finland, and the Berlin-based nonprofit Energy Watch Group.

In a study by the International Renewable Energy Agency, the global weighted average levelized cost of electricity of utility-scale solar photovoltaic has fallen 73 percent since 2010, to 10 cents per kWh for projects commissioned in 2017. A report released in January 2018 by Bloomberg New Energy Finance said $333.5 billion was invested globally in clean-energy projects during 2017.

Despite the political debate that surrounds renewable energy and fossil fuels, countries, large companies, and major cities around the world are taking meaningful action on renewable-energy development. For example, more than one third of China’s total installed capacity of power and generated electricity in 2017 came from renewable resources, according to a China Daily article. The European Union is raising its target for the amount of energy it consumes from renewable sources to 32 percent by 2030, The Guardian reported. India announced last year that it had set a goal of renewable energy capacity to 175 gigawatts by 2022, according to Mongabay.

Apple says its global facilities are powered with 100 percent clean energy.

New York state has committed to spending $1.4 billion to advance 26 large-scale renewable energy projects. The initiative is expected to generate enough clean, renewable energy to power more than 430,000 homes across the state.

OIL-RICH STATE COMMITS TO RENEWABLES

Texas, home to many oil and gas industries, is earning a reputation as a leader in renewable energy as well. The state set its renewable-energy policy in 1999 with its Renewable Portfolio Standard legislation, which restructured the electricity market. Today Texas has more than 10,000 wind turbines with 21,450 megawatts of installed capacity and is the sixth-largest wind-energy producer in the world. That’s thanks in part to exploiting the strong winds of west Texas.

The state is building transmission lines to move the electricity from its remote regions its large cities. Last year it had 21,751 MW of installed wind capacity, the most of any state in the nation. Texas leads the United States in wind-powered generation, with more than one fourth of the nation’s total last year. As a result, retail electricity prices have decreased well below the U.S. average: about 8.4 cents per kWh in 2017, compared with the U.S. average of 10.5 cents.

Texas plans to increase wind-energy capacity by 8,700 megawatts by the end of this year. Renewables are expected to account for more than 25 percent of the total electricity generated this year, according to the Electric Reliability Council of Texas.

Georgetown, Texas, with a population of 65,000, is one of the first U.S. cities to be 100 percent powered by renewable energy. The city gets its renewable energy from two wind farms and a solar facility. The plants cover the city’s 170-MW peak power demand, with enough left over to sell to the state electric grid. Georgetown is an example of what the future of energy might look like.

Energy policymakers in Texas say R&D in technologies related to renewable energy will accelerate a cost-effective transformation. Experts, power engineers, and researchers are engaged in the state’s energy transformation to renewable sources. For example, researchers at the University of TexasEnergy Institute, which has more than 300 experts and a budget of $100 million, are leading groundbreaking studies of technologies that cover the new spectrum of renewable energy.

I attended this year’s UT Energy Week, the annual meeting the university holds in Austin with energy experts from industry, academia, government, and regulatory agencies, as well as nonprofit organizations. We discussed some of the most vital energy issues facing society. Held from 4 to 8 February, the event attracted 600 people. Panels discussed the adequacy of Texas’s electric grid, prospects for large-scale energy storage, electric vehicles, and more.

One of the most important discussions addressed how to globally achieve 100 percent renewable energy sources. That panel also addressed which energy technologies are vital for the transition, as well as challenges such as battery storage.

To learn more about Energy Week, you can view the complete program and a video.

IEEE Senior Member Qusi Alqarqaz is an electrical engineer with more than 28 years of experience in the power industry. He writes about technology, works as a consultant, and mentors younger engineers and students. He is a contributor to The Instituteas well as the Analog, a newsletter for the IEEE Central Texas Section. He previously worked in Qatar and the United Arab Emirates.

The Conversation (0)

Get unlimited IEEE Spectrum access

Become an IEEE member and get exclusive access to more stories and resources, including our vast article archive and full PDF downloads
Get access to unlimited IEEE Spectrum content
Network with other technology professionals
Establish a professional profile
Create a group to share and collaborate on projects
Discover IEEE events and activities
Join and participate in discussions

The Inner Beauty of Basic Electronics

Open Circuits showcases the surprising complexity of passive components

5 min read
Vertical
A photo of a high-stability film resistor with the letters "MIS" in yellow.
All photos by Eric Schlaepfer & Windell H. Oskay
Blue

Eric Schlaepfer was trying to fix a broken piece of test equipment when he came across the cause of the problem—a troubled tantalum capacitor. The component had somehow shorted out, and he wanted to know why. So he polished it down for a look inside. He never found the source of the short, but he and his collaborator, Windell H. Oskay, discovered something even better: a breathtaking hidden world inside electronics. What followed were hours and hours of polishing, cleaning, and photography that resulted in Open Circuits: The Inner Beauty of Electronic Components (No Starch Press, 2022), an excerpt of which follows. As the authors write, everything about these components is deliberately designed to meet specific technical needs, but that design leads to “accidental beauty: the emergent aesthetics of things you were never expected to see.”

From a book that spans the wide world of electronics, what we at IEEE Spectrum found surprisingly compelling were the insides of things we don’t spend much time thinking about, passive components. Transistors, LEDs, and other semiconductors may be where the action is, but the simple physics of resistors, capacitors, and inductors have their own sort of splendor.

High-Stability Film Resistor

A photo of a high-stability film resistor with the letters "MIS" in yellow.

All photos by Eric Schlaepfer & Windell H. Oskay

This high-stability film resistor, about 4 millimeters in diameter, is made in much the same way as its inexpensive carbon-film cousin, but with exacting precision. A ceramic rod is coated with a fine layer of resistive film (thin metal, metal oxide, or carbon) and then a perfectly uniform helical groove is machined into the film.

Instead of coating the resistor with an epoxy, it’s hermetically sealed in a lustrous little glass envelope. This makes the resistor more robust, ideal for specialized cases such as precision reference instrumentation, where long-term stability of the resistor is critical. The glass envelope provides better isolation against moisture and other environmental changes than standard coatings like epoxy.

15-Turn Trimmer Potentiometer

A photo of a blue chip
A photo of a blue chip on a circuit board.

It takes 15 rotations of an adjustment screw to move a 15-turn trimmer potentiometer from one end of its resistive range to the other. Circuits that need to be adjusted with fine resolution control use this type of trimmer pot instead of the single-turn variety.

The resistive element in this trimmer is a strip of cermet—a composite of ceramic and metal—silk-screened on a white ceramic substrate. Screen-printed metal links each end of the strip to the connecting wires. It’s a flattened, linear version of the horseshoe-shaped resistive element in single-turn trimmers.

Turning the adjustment screw moves a plastic slider along a track. The wiper is a spring finger, a spring-loaded metal contact, attached to the slider. It makes contact between a metal strip and the selected point on the strip of resistive film.

Ceramic Disc Capacitor

A cutaway of a Ceramic Disc Capacitor
A photo of a Ceramic Disc Capacitor

Capacitors are fundamental electronic components that store energy in the form of static electricity. They’re used in countless ways, including for bulk energy storage, to smooth out electronic signals, and as computer memory cells. The simplest capacitor consists of two parallel metal plates with a gap between them, but capacitors can take many forms so long as there are two conductive surfaces, called electrodes, separated by an insulator.

A ceramic disc capacitor is a low-cost capacitor that is frequently found in appliances and toys. Its insulator is a ceramic disc, and its two parallel plates are extremely thin metal coatings that are evaporated or sputtered onto the disc’s outer surfaces. Connecting wires are attached using solder, and the whole assembly is dipped into a porous coating material that dries hard and protects the capacitor from damage.

Film Capacitor

An image of a cut away of a capacitor
A photo of a green capacitor.

Film capacitors are frequently found in high-quality audio equipment, such as headphone amplifiers, record players, graphic equalizers, and radio tuners. Their key feature is that the dielectric material is a plastic film, such as polyester or polypropylene.

The metal electrodes of this film capacitor are vacuum-deposited on the surfaces of long strips of plastic film. After the leads are attached, the films are rolled up and dipped into an epoxy that binds the assembly together. Then the completed assembly is dipped in a tough outer coating and marked with its value.

Other types of film capacitors are made by stacking flat layers of metallized plastic film, rather than rolling up layers of film.

Dipped Tantalum Capacitor

A photo of a cutaway of a Dipped Tantalum Capacitor

At the core of this capacitor is a porous pellet of tantalum metal. The pellet is made from tantalum powder and sintered, or compressed at a high temperature, into a dense, spongelike solid.

Just like a kitchen sponge, the resulting pellet has a high surface area per unit volume. The pellet is then anodized, creating an insulating oxide layer with an equally high surface area. This process packs a lot of capacitance into a compact device, using spongelike geometry rather than the stacked or rolled layers that most other capacitors use.

The device’s positive terminal, or anode, is connected directly to the tantalum metal. The negative terminal, or cathode, is formed by a thin layer of conductive manganese dioxide coating the pellet.

Axial Inductor

An image of a cutaway of a Axial Inductor
A photo of a collection of cut wires

Inductors are fundamental electronic components that store energy in the form of a magnetic field. They’re used, for example, in some types of power supplies to convert between voltages by alternately storing and releasing energy. This energy-efficient design helps maximize the battery life of cellphones and other portable electronics.

Inductors typically consist of a coil of insulated wire wrapped around a core of magnetic material like iron or ferrite, a ceramic filled with iron oxide. Current flowing around the core produces a magnetic field that acts as a sort of flywheel for current, smoothing out changes in the current as it flows through the inductor.

This axial inductor has a number of turns of varnished copper wire wrapped around a ferrite form and soldered to copper leads on its two ends. It has several layers of protection: a clear varnish over the windings, a light-green coating around the solder joints, and a striking green outer coating to protect the whole component and provide a surface for the colorful stripes that indicate its inductance value.

Power Supply Transformer

A photo of a collection of cut wires
A photo of a yellow element on a circuit board.

This transformer has multiple sets of windings and is used in a power supply to create multiple output AC voltages from a single AC input such as a wall outlet.

The small wires nearer the center are “high impedance” turns of magnet wire. These windings carry a higher voltage but a lower current. They’re protected by several layers of tape, a copper-foil electrostatic shield, and more tape.

The outer “low impedance” windings are made with thicker insulated wire and fewer turns. They handle a lower voltage but a higher current.

All of the windings are wrapped around a black plastic bobbin. Two pieces of ferrite ceramic are bonded together to form the magnetic core at the heart of the transformer.

This article appears in the February 2023 print issue.

{"imageShortcodeIds":[]}