Types of Electricity - Static and Current

Electrical resistance is the opposition to the flow of electric current in a material. It is measured in ohms (Ω) and depends on the conductor’s length, thickness, material, and temperature.

What is Electrical Resistance?

Electrical resistance is a fundamental concept in engineering that defines how much a material opposes the flow of electric current. Measured in ohms (Ω), resistance (Ω) plays a crucial role in circuit design, power distribution, and electronic applications.

✅ Measured in ohms (Ω) and calculated using Ohm’s Law

✅ Influenced by material, length, area, and temperature

✅ Key factor in circuit safety, design, and energy loss

Think of electricity moving like water through a pipe. If the pipe is narrow or obstructed, less water flows through it. Similarly, in a wire or conductor, certain materials make it harder for electrons to move freely. This obstruction results in energy loss, often seen as heat.

The ease or difficulty of electric charge movement depends on the conductivity of a material. Metals like copper allow current to flow easily, while rubber or glass inhibit it entirely. This behavior plays a key role in how systems are designed and protected. Discover how resistors are used in circuits to manage voltage and protect components by providing controlled resistance.

Electrical Resistance – Example Values by Material/Component

Electrical Resistance Definition

Several factors affecting electrical resistance include the type of material, temperature, and the dimensions of the conductor. When an electric charge moves through a material, its ease of flow depends on the material’s conductivity. A high-conductivity material allows charges to move more freely, resulting in lower resistance. The resistance of a conductor increases with its length and decreases with its cross-sectional area. Therefore, the resistance of a wire is directly related to both its physical properties and the material from which it is made. The resistance of a conductor depends heavily on its length and cross-sectional area, as outlined in our resistance formula breakdown.

This opposing property is quantified using Ohm’s Law:

R = V / I

Where:

• R is the resistive value in ohms

• V is voltage (volts)

• I is current (amperes)

Another useful expression involves material properties:

R = ρ × (L / A)

Where:

• ρ is resistivity (material-specific)

• L is length

• A is cross-sectional area

These formulas show that the longer or thinner the conductor, the harder it is for current to move through it.

Unit of Electrical Resistance – The Ohm (Ω)

The ohm is the SI unit of resistance, named after German physicist Georg Ohm. One ohm is defined as the resistance between two points of a conductor when a potential difference of one volt causes a current of one ampere to flow.

Common multiples:

• kΩ (kilo-ohm) = 1,000 ohms

• MΩ (mega-ohm) = 1,000,000 ohms

Resistance can be measured using a multimeter, and is especially important in designing and troubleshooting power  and electronic circuits. To understand how voltage and resistance interact in a circuit, see our guide on Ohm’s Law.

Ohm’s Law and Circuit Function

Ohm’s Law helps us understand how voltage, current, and resistance relate. For example:

• Increase the resistive load, and current drops.

• Increase voltage with fixed resistance, and current rises.

These principles help control energy flow, prevent overloads, and design efficient systems.

Measuring and Expressing Opposition

The ohm (Ω) is the standard unit used to quantify this phenomenon. One ohm means that a current of one ampere flows when one volt is applied. Components with fixed values, like resistors, are labelled accordingly—e.g., 100 Ω, 1 kΩ, or 1 MΩ.

To measure the current-limiting capacity of a material, a digital multimeter is used. It applies a small voltage and calculates the resulting current flow to determine the opposition level. If you're working with different wire types, explore the unit of electrical resistance for conversion insights and resistance ranges.

Real-World Examples of Resistance

• Heating Elements: Toasters, ovens, and electric heaters utilize high-resistance materials, such as nichrome wire.

• Power Transmission: Long-distance wires are designed with low resistance to reduce energy loss as heat.

• Electronic Components: Resistors regulate current in circuits, protecting components from overload.

For real-world scenarios involving current flow, our article on voltage drop explains how resistance affects electrical efficiency over distance.

Factors Affecting Electrical Resistance

• The resistance of a conductor depends on:

  • Material – copper vs. aluminum vs. nichrome

  • Length – longer wires restrict current more

  • Thickness – wider wires allow easier flow

  • Temperature – many materials resist current more when heated

  Thus, the resistance of a wire can vary dramatically depending on where and how it’s used. Materials with high conductivity (like silver or copper) allow electrons to move with minimal restriction, whereas poor conductors like rubber greatly hinder charge movement.

Superconductors – Zero Resistance?

In some materials, when cooled to extremely low temperatures, resistance drops to zero. These superconductors enable electricity to flow without energy loss, but their use is limited to specialized fields, such as MRI machines or experimental power lines, due to cost and cooling requirements.

Frequently Asked Questions

What causes electrical resistance?

It results from collisions between electrons and atoms in a conductor, which convert energy into heat.

What is the formula for calculating it?

 R = V/I or R = ρ × (L / A)

How is it measured?

With a multimeter in ohms (Ω), using a small test voltage and measuring current. Learn how instruments like a digital multimeter are used to measure opposition to current flow in electrical systems.

Why is this concept important?

It controls current flow, prevents damage, and enables functions like heating or dimming.

Can resistance ever be zero?

Yes—in superconductors under specific extreme conditions.

Electrical resistance is a foundational concept in understanding how electricity behaves in materials and systems. From household wiring to high-voltage power lines and sensitive electronics, it plays a crucial role in determining safety, efficiency, and performance. For a broader view on electric flow and material response, read about electrical conductivity and current electricity.

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Difference Between AC and DC explains alternating current vs direct current, waveform shape, frequency, voltage, polarity, rectification, inversion, power transmission, and typical uses in electronics, grids, batteries, and power supplies.

What Is the Difference Between AC and DC?

AC reverses direction and frequency; DC is unidirectional. They differ in waveform, voltage, and uses.

✅ AC: sinusoidal waveform; DC: steady line

✅ AC frequency varies by region (50/60 Hz)

✅ Rectifiers convert AC to DC; inverters convert DC to AC

The difference between AC and DC electrical currents is crucial to understand their unique characteristics and diverse applications. By examining the electron flow, voltage variation, power transmission, and safety implications of each current type, we can better appreciate the complex electrical systems that power our daily lives. This comprehensive article offers a deeper understanding of the fundamental distinctions between AC and DC currents, revealing their significance in electricity. For foundational context, see a concise definition of electricity that frames these distinctions clearly.

Two primary types of current dominate the world of electricity: alternating current (AC) and direct current (DC). To understand the difference, we need to explore their unique characteristics, applications, and the principles behind their operation. This comprehensive guide will delve into the details of each electrical current, providing examples and formulas for greater clarity. A broader primer on charge flow is available in this overview of current electricity for readers building fundamentals.

AC (alternating current) and DC (direct current) differ fundamentally in the flow of electrons. In an alternating current, the flow of electrons periodically reverses direction, following a sinusoidal waveform. The waveform is described by the formula V(t) = Vm * sin(2 * π * f * t), where Vm is the maximum voltage, f is the frequency, and t is time. On the other hand, in a direct current, the flow of electrons is constant and unidirectional, resulting in a steady voltage level. For a deeper explanation of sinusoidal behavior, consult this alternating current resource to connect theory with practice.

What is AC electrical current, and how is it measured?

AC (alternating current) is an electrical current in which the flow of electrons periodically reverses direction. Unlike direct current (DC), where the electrons flow in a single, constant direction, alternating current alternates between positive and negative values following a sinusoidal waveform.

AC electrical current is measured in several ways:

Amplitude: The maximum value of the current reached during each cycle is called the amplitude. This is the peak value of the sinusoidal waveform and is typically measured in amperes (A).

RMS (Root Mean Square) value: RMS value is a more practical measurement representing the AC current's effective value. The equivalent DC value would produce the same amount of power as the AC current. To calculate the RMS value of an AC current, you can use the formula I_RMS = I_peak / √2, where I_peak is the peak amplitude of the current.

Frequency: The frequency of an AC current refers to the number of cycles it undergoes per second. It is typically measured in hertz (Hz). In most countries, the standard frequency for AC power systems is either 50 Hz or 60 Hz.

Phase: In AC circuits, multiple currents or voltages may exist with the same frequency but different phase angles. The phase angle is the relative position of the waveform in a complete cycle, measured in degrees (°) or radians. Therefore, it is essential to consider the phase when dealing with multiple AC sources, as it can affect the overall performance of an electrical system.

These measurements are essential for characterizing and analyzing AC electrical currents, allowing engineers and technicians to understand their properties and optimize their use in various applications. For newcomers, this basic electricity primer can reinforce these concepts before moving to advanced analysis.

What is DC electrical current, and how is it measured?

DC (direct current) is a type of electrical current where the flow of electrons is constant and unidirectional. Unlike AC (alternating current), which periodically reverses the direction of electron flow, direct current maintains a consistent flow of electrons from the negative to the positive terminal of a power source. A quick reference on terminology is available in this DC current guide for consistent notation across texts.

DC electrical current is typically measured in a few ways:

Amperes (A): The most common method of measuring DC current is in amperes or amps. An ampere represents the rate of flow of electric charge through a conductor, which remains constant over time in the case of DC. Ammeters or multimeters are typically used to measure DC current in a circuit.

Voltage (V): Voltage is the electrical potential difference between two points in a circuit. For DC circuits, the voltage remains constant over time, providing a stable and predictable power source. The voltage across a power source or components in a DC circuit can be measured using a voltmeter or a multimeter.

Power (W): Power is the rate at which electrical energy is transferred in a circuit. In a DC circuit, power can be calculated using the formula P = V * I, where P is power, V is voltage, and I is current. Power can also be measured directly using specialized equipment like wattmeters.

Resistance (Ω): Resistance is the opposition a conductor offers to the flow of electric current. In a DC circuit, the relationship between voltage, current, and resistance can be described by Ohm's Law, which states V = I * R, where V is voltage, I is current, and R is resistance. Resistance can be measured using an ohmmeter or a multimeter with a resistance measurement function.

These measurements are essential for characterizing and analyzing DC electrical currents, allowing engineers and technicians to understand their properties and optimize their use in various applications, such as batteries, solar panels, and electronic devices. For additional background and historical context, see this direct current explainer covering uses and standards.

Voltage Variation

Voltage variation is an essential aspect that distinguishes AC and DC current. In an AC system, the voltage continuously varies, oscillating between positive and negative values according to the sinusoidal waveform. In contrast, DC voltage remains constant, providing a stable and predictable power source essential for many electrical devices.

Power transmission is another area where AC and DC differ significantly. Alternating current is primarily used for transmitting electricity over long distances due to its ability to utilize transformers. These transformers can adjust the voltage levels, enabling the efficient transmission of electrical energy from power plants to households and businesses. The transmission efficiency is enhanced by reducing current with high voltage and low resistance power lines, which follows the formula P = VI, where P is power, V is voltage, and I is current. On the other hand, direct current is employed in short-range applications. It has gained renewed interest in direct high-voltage current (HVDC) transmission systems for their low losses and efficient long-distance transmission.

Various applications require different electrical current types, making choosing between AC and DC crucial. For example, AC is preferred for most household appliances, such as refrigerators, washing machines, and air conditioners. The power grid provides AC; devices like transformers can easily convert it to the required voltage levels. Conversely, DC is ideal for low-voltage electronics like smartphones, laptops, LED lights, electric vehicles and solar panels that require a stable and consistent power supply. A structured comparison of categories is outlined in this overview of electricity types that helps align choices with applications.

Transformers and converters are key components in AC and DC circuits. In AC systems, transformers use electromagnetic induction to step up or down voltage levels, following the formula Vs/Vp = Ns/Np, where Vs and Vp are the secondary and primary voltages Ns and Np are the number of turns in the secondary and primary coils. In DC systems, converters change voltage levels or convert between AC and DC current power sources using devices like rectifiers and inverters.

Safety implications are paramount when dealing with AC and DC. Both types of electrical current pose potential hazards, including electric shock, burns, and fires. However, AC may be perceived as more dangerous due to its ability to cause muscle contractions, making it difficult to release an electrified object. Regardless, modern safety measures such as grounding, circuit breakers, and fuses have significantly mitigated the risks associated with both types of electrical current.

The unique properties of both currents enable them to serve a wide range of applications, from powering homes and industrial facilities to running delicate electronic devices and renewable energy systems. By grasping the intricacies of voltage, frequency, waveform, conversion, and safety measures, individuals can make informed decisions when choosing between alternating and direct current for specific purposes.

Moreover, the continuing advancements in power transmission technologies, such as direct high-voltage current (HVDC) transmission systems, are bridging the gap between alternating and direct current applications, allowing for more efficient and flexible electricity infrastructure. This progress showcases the importance of understanding both types of electrical currents and their evolving roles in our increasingly interconnected world.

One can explore real-world examples of their use to appreciate the difference between AC and DC further. For example, AC power is harnessed in large-scale power plants, such as coal-fired plants and hydroelectric facilities, which produce electricity using rotating magnets to generate alternating current. In contrast, DC power is often found in batteries, solar panels, and fuel cells, which constantly rely on steady magnetism or chemical reactions to flow electrons.

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Lenz’s Law is a principle of electromagnetic induction stating that induced current flows in a direction that opposes the change in magnetic flux producing it. This rule ensures energy conservation and explains how circuits, coils, generators, and transformers behave in changing fields.

What is Lenz’s Law?

Lenz’s Law, rooted in Faraday’s Law of Induction, states that the direction of an induced current or electromotive force (emf) always opposes the change in magnetic flux that produced it. This principle safeguards conservation of energy in electromagnetic systems.

✅ Explains opposing force in induced current and magnetic fields

✅ Fundamental to understanding circuits, transformers, and generators

✅ Practical in energy conversion, electric motors, and induction device

Lenz's Law, named after the Russian physicist Heinrich Lenz (1804-1865), is a fundamental principle in electromagnetism. It states that the direction of the induced electromotive force (emf) in a closed conducting loop always opposes the change in magnetic flux that caused it. This means that the induced current creates a magnetic field that opposes the initial change in magnetic flux, following the principles of conservation of energy. A strong grounding in basic electricity concepts makes it easier to see why Lenz’s Law is central to modern circuit design.

Understanding Lenz's Law enables us to appreciate the science behind various everyday applications, including electric generators, motors, inductors, and transformers. By exploring the principles of Lenz's Law, we gain insight into the inner workings of the electromagnetic world that surrounds us. Engineers use this principle when designing three-phase electricity systems and 3-phase power networks to maintain energy balance.

Lenz's Law, named after the Russian physicist Heinrich Lenz (1804-1865), is a fundamental principle that governs electromagnetic induction. It states that the induced electromotive force (emf) in a closed conducting loop always opposes the change in magnetic flux that caused it. In simpler terms, the direction of the induced current creates a magnetic field that opposes the initial change in magnetic flux. 

Lenz's Law is a fundamental law of electromagnetism that states that the direction of an induced electromotive force (EMF) in a circuit is always such that it opposes the change that produced it. Mathematically, Lenz's Law can be expressed as:

EMF = -dΦ/dt

Where EMF is the electromotive force, Φ is the magnetic flux, and dt is the change in time. The negative sign in the equation indicates that the induced EMF is in the opposite direction to the change in flux.

Lenz's Law is closely related to Faraday's Law of electromagnetic induction, which states that a changing magnetic field induces an EMF in a circuit. Faraday's Law can be expressed mathematically as:

EMF = -dΦ/dt

where EMF is the electromotive force, Φ is the magnetic flux, and dt is the change in time.

Ampere's Law and the Biot-Savart Law are also related to Lenz's Law, as they describe the behaviour of electric and magnetic fields in the presence of currents and charges. Ampere's Law states that the magnetic field around a current-carrying wire is proportional to the current and the distance from the wire. The Biot-Savart Law describes the magnetic field produced by a current-carrying wire or a group of wires. Because Lenz’s Law governs the behavior of induced currents, it directly complements Ampere’s Law and the Biot-Savart Law in explaining magnetic fields.

Together, these laws provide a complete description of the behaviour of electric and magnetic fields in various situations. As a result, they are essential for understanding the operation of electric motors, generators, transformers, and other devices.

To better understand Lenz's Law, consider the scenario of a bar magnet moving toward a coil of wire. When the magnet moves closer to the coil, the number of magnetic field lines passing through the coil increases. According to Lenz's Law, the polarity of the induced emf in the coil is such that it opposes the increase in magnetic flux. This opposition creates an induced field that opposes the magnet's motion, ultimately slowing it down. Similarly, when the magnet is moved away from the coil, the induced emf opposes the decrease in magnetic flux, creating an induced field that tries to keep the magnet in place.

The induced field that opposes the change in magnetic flux follows the right-hand rule. If we hold our right hand around the coil such that our fingers point in the direction of the magnetic field lines, our thumb will point in the direction of the induced current. The direction of the induced current is such that it creates a magnetic field that opposes the change in the magnetic flux.

The pole of the magnet also plays a crucial role in Lenz's Law. When the magnet's north pole moves towards the coil, the induced current creates a magnetic field that opposes the north pole's approach. Conversely, when the magnet's south pole moves towards the coil, the induced current creates a magnetic field that opposes the south pole's approach. The direction of the induced current follows the right-hand rule, as we discussed earlier.

It is related to Faraday's Law of Electromagnetic Induction, which explains how a changing magnetic field can induce an electromotive force (emf) in a conductor. Faraday's Law mathematically describes the relationship between the induced electromotive force (emf) and the rate of change of magnetic flux. It follows Faraday's Law, as it governs the direction of the induced emf in response to the changing magnetic flux. To fully understand how electromagnetic induction works, it is helpful to see how Faraday’s discoveries laid the foundation for Lenz’s Law.

It is also related to the phenomenon of eddy currents. Eddy currents are loops of electric current induced within conductors by a changing magnetic field. The circulating flow of these currents generates their magnetic field, which opposes the initial magnetic field that created them. This effect is in line with Lenz's Law and has practical applications, such as in the braking systems of trains and induction cooktops.

Lenz's Law has numerous practical applications in our daily lives. For example, it plays a significant role in the design and function of electric generators, which convert mechanical energy into electrical energy. In a generator, a rotating coil experiences a changing magnetic field, resulting in the generation of an electromotive force (emf). The direction of this induced emf is determined by Lenz's Law, which ensures that the system conserves energy. Similarly, electric motors operate based on Lenz's Law. In an electric motor, the interaction between the magnetic fields and the induced electromotive force (emf) creates a torque that drives the motor. In transformers, including 3-phase padmounted transformers, Lenz’s Law explains why flux changes are controlled for efficiency and safety.

Lenz's Law is an essential concept in the design of inductors and transformers. Inductors are electronic components that store energy in their magnetic field when a current flows through them. They oppose any change in the current, following the principles of Lenz's Law. Transformers, which are used to transfer electrical energy between circuits, utilize the phenomenon of electromagnetic induction. By understanding it, engineers can design transformers.

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Electricity demand Canada drives load forecasting, grid reliability, peak demand management, renewable integration, and capacity planning across provinces, informing energy consumption trends, transmission constraints, demand response programs, and ISO market operations.

What Is Electricity Demand Canada?

It is the national electrical load across sectors guiding forecasting, grid planning, and reliability.

✅ Provincial load profiles and peak diversity analysis

✅ Demand response and time-of-use optimizing peak loads

✅ Transmission constraints and capacity expansion planning

Electricity Demand in Canada will continue to put, in the longer term, upward pressure on prices for consumers in both regulated and restructured or deregulated markets. For context, market fundamentals and policy design both shape electricity prices across provinces today, influencing bills over time.

These dynamics play out within an integrated electric power system that balances reliability, affordability, and decarbonization goals.

These pricing impacts will be felt due to the cost of developing new generation and transmission facilities in order to replace ageing infrastructure and due to the increased use of renewable sources of generation (e.g., wind, solar, biomass). Continued strength of oil and gas prices are expected to keep electricity prices higher in regions that rely on natural gas and oil products as input fuels for power generation. Understanding the mix of hydro, wind, solar, nuclear, and gas requires a grasp of how electricity is generated across Canada’s grid components.

With the exception of Ontario (due to its large summer seasonal air conditioning requirement for electricity demand, Canada is a winter-peaking system and so the highest demand loads usually occur in the winter. However, for provinces that have competitive wholesale markets (e.g. Alberta and Ontario), near-term price pressures could result from the increase in summer cooling demand. Prices could also experience additional upward pressure from fuels used to generate electricity; namely, oil and natural gas. These pressures could be further supported by unusual weather events, unplanned generation outages and transmission system failures. If wholesale price pressures are to be passed on to consumers, the cost impact would likely not be felt immediately. Instead, such costs would need to go through a review process in all provinces and be approved by the energy regulatory board of that respective province. Tight reserve margins can constrain electricity supply during extreme temperature events, amplifying short-term price volatility.

Consumer prices or "rates" vary for several reasons:

In many jurisdictions, the total electricity cost combines generation, transmission, distribution, and rider charges that appear separately on bills.

• variation in generation costs; prices in hydro-based provinces tend to be lower (e.g., British Columbia, Manitoba and Quebec);
• customer class (e.g., residential, commercial, industrial);
• residential rates tend to be higher than commercial and industrial rates;
• amount of energy consumed in a given period (e.g., rates may vary based on customer consumption);
• time-of-use pricing (e.g., some consumers have access to time of use meters that show lower charges for electricity during off peak periods);
• and capability to switch to lower cost fuels (e.g. industrial customers)

Consumers in deregulated provinces can compare plans from an electricity supplier to align contract terms and risk with their usage profile.

Electricity demand Canada in peak periods typically occurs during the winter months, although, at times, Ontario and Quebec experience peak electricity demand in the summer months due to increased use of air conditioning units. Spring and fall tend to be shoulder seasons with lower demand. Seasonal patterns also influence maintenance schedules for electricity generation across provinces, which can tighten supply during cold snaps or heat waves.

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Capacitors store electrical energy via a dielectric, offering capacitance for filtering, smoothing, and decoupling in AC/DC circuits, RC networks, and power supplies, spanning ceramic, film, and electrolytic types with distinct impedance profiles.

What Are Capacitors?

Capacitors store charge using a dielectric, providing capacitance for filtering, timing, and decoupling in circuits.

✅ Types: ceramic, film, tantalum, electrolytic; surface-mount or through-hole

✅ Functions: decoupling, bulk energy storage, timing, AC coupling

✅ Key specs: capacitance, voltage rating, ESR/ESL, tolerance, ripple

Capacitors for Power Factor Correction

It is desirable to add shunt capacitors in the load area to supply the lagging component of current with a positive negative charging electrons. The cost is frequently justified by the value of circuit and substation capacity released and/or reduction in losses. Installed cost of shunt capacitors is usually least on primary distribution systems and in distribution substations. For foundational context, see what a capacitor is to understand reactive power roles.

The application of shunt capacitors to a distribution feeder produces a uniform voltage boost per unit of length of line, out to its point of application. Therefore, it should be located as far out on the distribution system as practical, close to the loads requiring the kilovars. There are some cases, particularly in underground distribution, where secondary capacitors are economically justified despite their higher cost per kilovar. The placement effectiveness also depends on capacitance characteristics relative to feeder impedance.

Development of low-cost switching equipment for capacitors has made it possible to correct the power factor to a high value during peak-load conditions without overcorrection during light-load periods. This makes it possible for switched capacitors to be used for supplementary voltage control. Time clocks, temperature, electric charge voltage, current flows, and kilovar controls are common actuators for high frequency capacitor switching. Utilities typically choose among several types of capacitors to balance switching duty and reliability.

Capacitor Installations

Capacitors for primary systems are available in 50- to 300-kvar single phase units suitable for pole mounting in banks of 3 to 12 units. Capacitors should be connected to the system through fuses so that a capacitor failure will not jeopardize system reliability or result in violent case rupture. When voltage ratings limit a single unit, engineers connect capacitors in series to distribute stress effectively.

Effect of Shunt Capacitors on Voltage

Proposed permanently connected capacitor applications should be checked to make sure that the voltage to some customers will not rise too high during light-load periods. Switched capacitor applications should be checked to determine that switching the capacitor bank on or off will not cause objectionable flicker in electronics. Selecting appropriate sizes in the standard unit of capacitance helps manage voltage rise and flicker.

Effect of Shunt Capacitors on Losses

The maximum loss reduction on a feeder with distributed load is obtained by locating positively negatively capacitor banks on the feeder where the capacitor kilovars is equal to twice the load kilovars beyond the point of installation. This principle holds whether one or more than one capacitor bank is applied to a feeder. To meet kvar targets with modular banks, utilities often add capacitance in parallel so reactive output scales predictably.

Capacitor kilovars up to 70% of the total kiovar load on the feeder can be applied as one bank with little sacrifice in the maximum feeder-loss discharge reduction possible with several capacitor banks.

A rule of thumb for locating a single capacitor bank on a feeder with uniformly distributed loads is that the maximum loss reduction can be obtained when the capacitor kilovars of the bank is equal to two-thirds of the kilovar load on the feeder. This bank should be located two-thirds of the distance out on the distributed feeder portion for object charging. Deviation of the capacitor bank location from the point of maximum loss reduction by as much as 10 per cent of the total feeder length does not appreciably affect the loss benefit. Therefore, in practice, in order to make the most out of the capacitor's loss reduction and voltage benefits, it is best to apply the capacitor bank just beyond the optimum loss-reduction location.

Batteries and capacitors seem similar as they both store and release electrical energy. However, there are crucial differences between them that impact their potential electronic applications due to how they function differently, depending on insulator material.

Supercapacitors

A capacitor battery aligns the molecules of a dielectric across an electric field to store energy. A supercapacitor aligns the charging of an electrolyte on either side of an insulator to store a double-layer charge.

Electrolytic capacitors consist of two or more conductive capacitors plate, separated by a dielectric. When an electric current enters the capacitor, the dielectric stops the flow and a charge builds up and is stored in an electric field between the metallic plates. Each capacitor is designed to have a particular capacitance (energy storage). When a capacitor is connected to an external circuit, a current will rapidly discharge. Plate area, separation, and dielectric constant together determine capacitance and thus energy density.

In a supercapacitor, there is no dielectric between conducting plates; rather, there is an electrolyte and a thin insulator such as cardboard or paper. When a current is introduced to the supercapacitor, ions build on either side of the insulator to generate a double layer of charge, no matter the capacitor charged. Supercapacitors are limited to low voltages, but very high capacitance frequencies, as a high voltage would break down the electrolyte. 

Batteries

There are different types of capacitor batteries, which detemine the capacitance of a capacitor. Different battery types are distinguished by their chemical makeup. The chemical unit, called the cell, contains three main parts; a positive terminal called the cathode, negative terminal called the anode, and the electrolyte. Batteries store electric energy. The battery charges and discharges through a chemical reaction that generates a voltage. The store of charge in the battery is able to provide a consistent DC voltage. In rechargeable batteries, the chemical energy that is converted into electricity can be reversed using an outside electrical energy to restore the charge of capacitors storing power in the batteries.

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