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The electricity we consume daily is generated from a wide variety of sources and processes, which convert different types of energy into electrical energy. To achieve this, renewable sources such as solar, wind, hydropower, and geothermal energy, which are increasingly important in contributing to the energy mix, as well as non-renewable sources, are used. From traditional plants based on traditional fuels to innovative renewable technologies, each method of electricity generation has its own characteristics in terms of efficiency and environmental impact. Understanding how the electricity that reaches our homes is produced and the technologies used in its generation allows us to appreciate the importance of moving toward more environmentally friendly energy systems.

What is electricity?

Electricity is a form of energy resulting from the movement of charged particles, such as electrons. This natural phenomenon has been harnessed by humanity to become one of the fundamental pillars of modern life. Thanks to electricity, it is possible to power everything from everyday electronic devices, such as smartphones and household appliances, to complex infrastructure, such as transportation systems and industrial networks.

Electricity can be produced from a variety of sources, both renewable and nonrenewable, including wind, water, traditional fuels, and solar energy. Furthermore, electricity can be transformed into other forms of energy, such as light, heat, or motion, making it a versatile and essential resource for the development of society.

Why is generating electricity so important today?

Power generation comprises all existing processes for transforming energy of any type (chemical, kinetic, mechanical, etc.) into electricity.

Electricity generation is fundamental in today's society, as it supports technological and economic development and directly impacts people's quality of life. Daily life as we know it depends largely on a constant electricity supply, and many of the comforts and advances achieved would disappear without this resource.

Diverse factors, such as a growing global population and digitalization, have forced industrial activity and power demand to boom in order to continue to meet society's needs. In that way, one of the challenges we face in the energy industry is efficiently guaranteeing the production and supply of electricity to citizens in an environmentally-friendly way.

Let's begin with the fact that many resources on our planet are limited, so the various types of renewable energy (solar, wind, hydropower etc.) are increasingly more important. The energy transition is the primary tool that companies, governments, and citizens possess for producing, distributing, and consuming energy, while reducing greenhouse gas (GHG) emissions. We're progressing toward an economy with a lower carbon footprint, in which energy efficiency and renewable energy play a fundamental role in slowing climate change.

How is electricity produced and distributed?

Have you ever wondered how power arrives to your home? Electricity passes through various points starting from where it is generated all the way until you press the light switch.

Energy generation process:

1. Obtaining energy from various primary sources

Electricity is a secondary energy source, therefore it must be produced from a primary source of energy, that is, from naturally-present resources. There are two ways of producing electricity:

  • From renewable primary energy sources, such as the wind, solar radiation, or ocean waves. 
  • Or from non-renewable primary energy sources, such as coal, natural gas, petroleum, or nuclear energy. 

2. Transforming energy into electricity

Once the energy is obtained, it is converted into electricity and transmitted from an electrical plant to an electrical substation. Electrical substations are fundamental for preparing electricity and guaranteeing proper voltage. The largest are located in the outskirts of cities, whereas much smaller ones can be located inside a building. 

3. Distributing electricity

The distributor is in charge of transmitting electricity from the substation to homes. The various distributors have set up the proper infrastructure to transport and distribute energy, and are tasked with maintaining it in good conditions. They're also responsible for electricity meters, and therefore, also for sending meter readings to the retailer. Consumers cannot choose their distributor; it's assigned based on location, but they may choose their retailer. 

4. Selling electricity

The power retailer is the company with which the consumer contracts their electricity supply. This company purchases energy from power generation companies and sells it to users, so that they may have electricity in their homes. It's also in charge of sending bills. Power can be sold and contracted in two ways:

  • Free market: according to specified conditions agreed to in a contract between the company and the user.
  • Regulated market: according to a system designed by the Government.

What are the sources of power generation?

Have you every wondered how electricity is produced? Depending on nature's capacity for generating each resource, energy sources can be classified as either renewable or non-renewable.

5 ways to generate power with primary sources

There are several ways to generate electricity using the primary energy sources available in nature. Below, we present five ways to produce electricity, each with its own advantages and applications, contributing to the supply of the electricity we use daily.

man from electricity company reviewing solar panels

Solar energy is obtained from sun radiation in the form of light, heat, and ultraviolet rays. And although they both are produced at solar plants, there are two different types: 

  • Photovoltaic solar energy, which transforms sunlight into electrcity using photovoltaic panels.
  • Solar thermal energy, which transforms the heat from the sun into electricity using solar thermal collectors.
woman walking with her bike through a field of grains with wind turbines in background

Wind energy is transformed into electricity through a wind turbine. Depending on the location of the wind farm, there are two types:

  • Onshore wind energy, located on land.
  • Offshore wind energy, located in the ocean.
Offshore wind turbines

It involves harnessing wind energy at sea to produce electricity through an installation of offshore wind turbines by anchoring them to the bottom of the sea or by using more modern and less invasive floating systems, which is increasingly more common.

Water flowing from a dam

Hydropower harnesses the force of moving water to produce electricity in hydropower plants. There are three type of these plants:

  • Storage hydropower plants use a large reservoir of a certain volume by means of a dam.
  • Run-of-river hydropower plants capture part of the water flowing in a river and diverts it towards the turbines in the plant.
  • Pumped-storage hydropower plants can convert the energy from the water into electricity and the other way around.
Geyser

Geothermal energy is the heat within the Earth that can be used to generate electricity, but it can only be harnessed in locations with specific physical conditions such as hot springs, geysers, or volcanoes.

Other ways of generating electricity

There are other ways to generate power although they're not as conventional. These are some examples: