Electricity is a form of energy, the flow of tiny electrons that are negatively charged. When there is a build up of electricity in one place, it's called static electricity, but when these move from one place to another, it's known as an electric current. Electricity is now one of our essential parts of nature and is one of the most widely used secondary energy sources that humans have harnessed. We get our electricity from the conversion of other energy sources, like natural gas, coal and nuclear power, which are known as primary sources. Mostly, towns and cities were built right alongside waterfalls, as these were the primary source of mechanical energy to turn water wheels so that energy and electricity could be produced - early generators if you will.
To be able to form a current that is closed, electrons have to flow freely along a closed path - also known as a circuit. These consist of electrical components that are connected with wires. These wires are usually copper or aluminium, which conduct electricity efficiently. The atomic structures of copper and aluminium are such that they have free electrons: these allow electricity to flow freely through them and they are also called insulators. One of the best examples of an insulator is rubber.
You can divide an electric current into two types: direct current and alternating current. Direct current has the electrons moving around a circuit in the same direction. Alternating current has the electrons continually reverse direction at a high rate.
Batteries are an excellent example of direct current, whereas power plant electricity that is sent to your house is alternating current. Direct current has electricity flowing in the same direction, between the positive and negative terminals of a battery at a low voltage. Alternating current can be generated with higher voltages over a much longer distance, and this is what is used to power the large appliances and light bulbs in your home.
How Is Electricity Measured?
Electricity is commonly measured in watts, which was named as such to honour James Watt, the man who invented the steam engine. One watt is a tiny amount of power, and it would take 750 watts to equal one horsepower. A kilowatt is the representation of 1,000 watts, and kilowatt-hour (kWh) is 1,000 watts working for one hour. A power plant or a person generate electricity over a period of time, and this is measured in kilowatt-hours.
Generation: How Do We Get Our Electricity?
An electric generator converts mechanical energy into electrical energy, and this is a process that depends on the relationship between magnetism and electricity. If a conductive material moves nearby to a magnetic field, an electric current is created. Large generators that are used in homes, businesses and the electric utility industry have stationary conductors, with a magnet attached to the rotating shaft inside a ring wrapped in wire. When the magnet turns, the wire has a small electric current induced in each section of the wire as it passes. These sections have a small, separate conductor of electricity and all of the smaller currents add up to one larger current. This is the current used to power your outlets and appliances.
It’s much better for the environment to combine diesel with natural oil because this means the emissions from the generator are lower and environmental impact overall is smaller. If that’s something that you care about and want to factor in to your final decision, you should definitely consider this option as a realistic possibility.
Electric power stations use machinery to drive an electric generator and these include;
- Water Wheels
Each of these devices can convert mechanical energy or chemical energy into electricity. The most common electricity generation methods include gas turbines, steam turbines, internal-combustion engines, wind turbines, and water turbines. Turbines convert the kinetic energy of moving fluid to mechanical energy and steam turbines are the most commonly used turbines in the US. These have a series of blades mounted through which steam is forced, which then rotate the shaft connected to the generator.
Natural fuels like coal, oil and natural gas can be burned in furnaces to heat water, which then makes steam and pushes the blades of the turbine. Steam trains work this way and were very popular for a very long time - before electric engines were invented.
There are four primary sources of natural generation; ones that don't involve steam power. Let's take a look at how they work:.
- Geothermal power comes directly from heat underneath the surface of the earth. Magma flows close to the surface, underground heating water into steam which is then used for steam-turbine plants. If this source of energy was used, power could be supplied to up to 20% of the needs of the US.
- Solar power, as you know, is taken from the sun. Solar panels on homes are currently used to power appliances and keep the heat going and lights on. The problem with solar power is that on a cloudy day, you cannot use it and the sun's energy is only available for a limited time in the day. It's also more expensive to convert the sun's energy toelectricity.
- Wind turbines can be seen in areas of empty land and even oceans nowadays, and wind power itself is derived from energy being converted into electricity. It's an expensive source of electricity production, and a turbine works the same way as a typical windmill.
- Biomass is another source of energy with which to produce electricity. the use of garbage and agricultural waste like wheat straw and corn cobs can also be used along with the wood to create electricity. The combustion of these elements creates steam that leads to the generation of electricity.
Ask anyone this question, and they will immediately call to mind a Mr. Benjamin Franklin and excitedly tell you all about his kite experiment. The thing is, no one answer to precisely invented electricity. It was a chain of inventions that led to the use of electric power that we know of today. The purest and most basic form of electricity is held in lightning, and it took many years and people to bring it from the skies during a storm to our everyday use. Below, we've created a timeline of names throughout history who were involved in the harnessing of electricity. Benjamin Franklin may have been credited with the discovery, but it wasn't just an effort on his part.
600BC: Thales of Miletus wrote about the charging of amber when it was rubbed - we now know this to be static electricity.
1600: The Greek word 'amber' translated to the English word 'electricity,' and William Gilbert did this.
1660: A machine was invented by Otto von Guericke to produce static electricity.
1675: The electric force of attraction and repulsion were observed by one Robert Boyle when he viewed this transmission through a vacuum.
1729: The conduction of electricity was discovered by Stephen Gray, which gave a whole new perspective on the idea of electricity.
1733: Charles Francois du Fay discovered that electricity comes in two forms, which he named as vitreous (+) and resinous (-). We know them today as positive and negative, as renamed by Benjamin Franklin and Ebenezer Kinnersley.
1745: The Leyden jar was invented by Pieter van Musschenbroek, which stored static electricity that could be discharged at once.
Electromagnetic Induction is one of the most significant discoveries in the history of electricity, and the invention led to a better understanding of how electric currents work.
1747: The Leyden Jar was shown to be discharged using a circuit by William Watson. The terms used - current and circuit - proved to break through the barrier to further experimentation.
Henry Cavendish began to measure the conductivity of materials and published those results.
Coulomb used maths to articulate the attraction between electrified bodies. This opened up an avenue to study quantitative electricity.
1752: A big year for electricity, as this was the year that Benjamin Franklin performed his famous risk - he flew a kite in a thunderstorm to prove that lightning was electrical. Luckily, he was not killed during this experiment! Through the Royal Society, Franklin was elected as a Fellow and honored with the Copley Medal a year later, in the appreciation of his work with electricity.
Michael Faraday played a part in the history of electricity by being the person that discovered a moving magnet inside a wire coil could generate electricity. This was what led to the build of the very first electric motor. Generators and transformers were built after that, and it's become a massive contribution to electromagnetism today.
Both Henry Cavendish, Coulomb, and Luigi Galvani contributed toward the practical uses of electricity and how it could be used.
1786: Galvani established the electrical basis of nerve impulses by using a spark to make frog muscles twitch.
Girolamo Cardano distinguished between electrical and magnetic forces with his writing.
Volta discovered that cathodes and anodes could be created through chemical reactions. The unit of difference is named 'volt' in his honor.
Thomas Edison was a notable name by discovering the electric bulb.
Nikola Tesla contributed to the electricity supply system that uses alternating current.