What is solar energy? [Complete guide on the subject]

When talking about alternatives to produce energy in a clean and economical way, understanding what solar energy is has become essential.

More than just a trend, photovoltaic technology already occupies a relevant space in the Brazilian electricity matrix: in 2024 alone, the country sured 39 gigawatts of installed power, with emphasis on generation on rooftops and small systems connected to the grid.

This growth is no coincidence. Solar energy combines technical feasibility, cost reduction and positive environmental impact — and has transformed everything from homes to large enterprises.

In this guide, you will see how this technology works, where it is applied and why it is at the center of discussions about the future of energy in Brazil. Keep reading!

What is solar energy?

Solar energy is energy that comes from the sun's radiation. This clean, renewable source can be converted into electricity using photovoltaic s or used directly to heat water, for example.

The main electrical conversion model is the photovoltaic system, which transforms sunlight into electrical current through the photovoltaic effect.

What is solar energy used for?

Solar energy has several applications, including:

• Residential, commercial and industrial electricity generation;
• Reduction of electricity costs;
• Water heating (in solar thermal systems);
• Energy autonomy in remote locations;
• Sustainability in public and private projects.

In addition to its direct benefits, solar energy plays an essential role in combating climate change.

According to the Brazilian Association of Photovoltaic Solar Energy (Absolar), since 2012 the sector has avoided the emission of 47,7 million tons of CO₂ in electricity generation in Brazil.

How does photovoltaic energy work?

​​Photovoltaic technology uses solar modules that capture sunlight and generate direct current electricity.

This current is then converted into alternating current by an inverter, making it compatible with the electrical grid and conventional equipment.

There are two main models of photovoltaic systems:

• Distributed generation: installation on roofs, facades or small plots of land, connected to the local electricity grid;
• Centralized generation: large solar plants, connected to the National Interconnected System (SIN).

Both contribute significantly to increasing the country's installed capacity and the choice between one or the other depends on factors such as the consumption profile, the purpose of the project and the technical and economic viability of the available area.

What is the economic and energy expansion outlook in Brazil?

​​The growth of solar energy in Brazil has been exponential. In 2024, the country sured 39 GW of installed capacity, including large-scale plants and distributed systems – which represents about 17% of the national electricity matrix.

Since 2012, investments in the sector have already exceeded R$189 billion, generating more than 1,1 million direct and indirect jobs.

The sector also s for R$51,6 billion in public revenue, driving socioeconomic development in all regions of the country.

Distributed generation s for 26,8 GW of this capacity, with a focus on residential, commercial and rural properties. Centralized generation s for around 12,2 GW, with plants expanding especially in the North and Northeast regions.

What are the types of solar energy?

There are three main ways to harness solar energy: photovoltaic, solar thermal and solar thermal. Understand the particularities of each type:

1. Photovoltaic solar energy

It uses photovoltaic modules to convert sunlight directly into electricity through photovoltaic cells.

The energy produced by photovoltaic s can be used to power machines, household appliances, lamps, electric cars or any type of equipment that requires electricity to operate.

2. Solar thermal energy

uses solar collectors to capture the sun's heat and heat fluids, such as water. This heated fluid can be used in domestic heating systems, in industrial processes or in swimming pools.

In addition, there is also heliothermal energy, also known as concentrating solar power (CSP).

It is a technology that uses mirrors or lenses to concentrate sunlight onto a single point, generating intense heat. This heat is then used to produce steam, which drives a turbine and generates electricity.

3. Solar thermal energy

Solar thermal energy can be used in a variety of ways, for example, large-scale electricity generation, thermal energy storage, industrial processes and water desalination.

Where can solar energy be applied?

Solar energy is a renewable and sustainable source of energy, with many applications in different areas. Here are some of the main sectors in which it can be applied:

• Distributed Generation (Photovoltaic): photovoltaic modules are used to generate electricity in homes, businesses and industries, reducing dependence on the electricity grid and lowering energy costs;
• Centralized Generation (Photovoltaic): large facilities that capture solar energy on a large scale and convert it into electricity to supply entire cities and regions;
• Solar thermal: used in homes, hotels and swimming pools to heat water efficiently, using solar collectors that capture the sun's heat;
• Water desalination: used to remove salt and other minerals from seawater, making it drinkable;
• Solar lights: solar s charge batteries during the day and provide lighting at night;
• Water pumps: used in rural areas for irrigation and water supply. They are powered by solar energy, eliminating the need for fossil fuels or grid electricity;
• Solar cookers: equipment that uses the sun's heat to cook food;
• Refrigeration systems: used to preserve food and medicine in remote areas where conventional electricity is not available;
• Solar chargers: small devices that use solar s to charge cell phones, laptops and other electronic devices;
• Electric vehicles: cars that use solar s to power their engines, reducing pollutant emissions.

What are the benefits of solar energy?

Photovoltaic solar energy has stood out as one of the most promising and sustainable sources for generating electricity in Brazil and around the world.

In addition to reducing energy costs, it contributes significantly to sustainable development, bringing positive impacts on several fronts. Find out more:

In the middle of the day

Solar energy is a clean, renewable and abundant source of energy. Unlike fossil fuels, it does not emit greenhouse gases or pollutants during power generation.

This directly contributes to reducing global warming, air pollution and carbon footprint.

For the society

The growth of the photovoltaic sector in Brazil has driven the generation of qualified jobs, promoting local economic development.

It is estimated that the sector has already created tens of thousands of direct and indirect jobs, from manufacturing to installation and maintenance of systems.

for companies

Companies that adopt solar energy obtain significant competitive gains: reduction in electricity bills, predictability of operating costs, enhancement of institutional image and alignment with ESG (Environmental, Social and Governance) practices, increasingly demanded by the market.

for consumers

For the end consumer, the main advantage is savings. The system can reduce the electricity bill by up to 95%.

Furthermore, the return on investment (ROI) is attractive, with an average payback of between 3 and 6 years, and a useful life of the systems exceeding 25 years.

How to implement a photovoltaic energy system?

Adopting solar energy requires technical and financial planning. Below, check out the main steps to implement an efficient and safe photovoltaic system:

Energy consumption analysis

This is the first step towards understanding the unit's consumption profile. Using energy bills, it is possible to determine the ideal system size.

Site assessment

The slope, orientation and shading of the roof or terrain directly impact the efficiency of solar generation. A technical analysis assesses the solar potential of the available area.

System sizing

Based on consumption and local conditions, the number of modules, inverters and other components needed to meet energy demand is calculated.

Choice of technology and equipment

The choice of solar s, inverters and structures must consider efficiency, quality, warranty and compatibility between the equipment.

Budget and hiring

After defining the project, a budget is drawn up. Choosing an experienced integrator company is essential to ensure safety, regulatory compliance and technical .

Design and approval

The electrical project must be prepared by a qualified professional and submitted for approval by the local distributor, in accordance with the standards of ANEEL and the dealership.

System installation

Installation must follow technical and safety standards, ensuring optimal performance and durability of the system. It is essential that it is carried out by a qualified team.

Inspection and connection to the network

After installation, the distributor carries out an inspection and authorizes the connection of the system to the electricity grid, allowing the generation and use of energy credits.

Monitoring and maintenance

The system must be monitored periodically to ensure expected performance. Preventive maintenance increases service life and avoids generation losses.

What are the main challenges of solar energy in Brazil?

Despite the significant growth of solar energy in the country, there are still important challenges to be faced. The main ones include:

• Bureaucracy and regulation: the process of connecting to the electricity grid and the constant regulatory changes can generate insecurity for investors and consumers;
• Financing and access to credit: although specific lines already exist, many Brazilians still face difficulties in obtaining attractive financing conditions;
• Technical capacitation: the sector demands qualified professionals, and there is a shortage in some regions of Brazil, which can compromise the quality of the facilities;
• Power grid infrastructure: in certain locations, the grid is not prepared to receive the increasing volume of distributed generation.

After all, is it worth investing in photovoltaic energy?

Yes, it is very worth it. Photovoltaic solar energy is one of the most advantageous sources for those seeking savings, sustainability and returns in the medium and long term.

Here are some concrete benefits:

• Immediate reduction in your electricity bill: consumers can save up to 95% on their monthly electricity bill;
• Property valuation: properties with photovoltaic systems have a higher market value;
• Sustainability: since 2012, solar energy in Brazil has prevented the emission of 47,7 million tons of CO₂;
• Job and income generation: the sector has already generated more than 1,1 million jobs, showing its economic potential.

Solar energy is already a consolidated reality in Brazil. For those seeking stability, financial return and positive environmental impact, the investment is worth it.

Want to delve deeper into the topic? Read all about it in Canal Solar and stay up to date with the best opportunities, trends and solutions in the photovoltaic sector.

Solar Energy FAQs

Below, we answer the most common questions to help you better understand how this technology works and why it is an excellent investment:

How much can you save on your electricity bill using solar energy?

With a well-designed system, it is possible to reduce your electricity bill by up to 95%. The exact savings depend on consumption, location of the property and characteristics of the installed system.

Does solar energy work on cloudy or rainy days?

Yes. Even with lower solar intensity, photovoltaic s continue to generate energy on cloudy or rainy days, although with lower efficiency. Production may decrease, but it does not stop completely.

Does the photovoltaic energy system work at night?

No. During the night, since there is no sunlight, the s do not produce energy. However, with the system connected to the grid (on-grid), the consumer can use the energy compensated for by the excess generation during the day.

What is the payback time for solar energy?

The average payback period for a residential photovoltaic system ranges from 4 to 7 years. After this period, the system continues to operate with low maintenance and generate savings for more than 20 years.

Do solar s need maintenance?

Yes, but it is minimal. The main recommendation is to periodically clean the boards (especially in areas with a lot of dust or pollution) and perform an annual technical inspection to ensure that all components are working properly.

Is it possible to zero the electricity bill?

Yes, it is possible to reset the consumption portion of the bill. However, minimum fees and charges such as the availability fee will continue to be charged by distributors, even with a positive energy balance.

Does solar energy increase property value?

Yes. Properties with photovoltaic solar systems are more valued on the market. In addition to sustainability, they offer long-term savings, which is an important attraction for buyers.

What is the power of solar energy?

The power of a photovoltaic system varies according to the project and consumption needs. In Brazil, we have already sured the 39 GW mark of installed power, including centralized and distributed generation.

Is solar energy a primary or secondary source of energy?

Solar energy is considered a primary source of energy because it comes directly from solar radiation — a natural, renewable and abundant source. It is converted directly into electrical energy by photovoltaic s, without the need for prior transformation.

Conclusion

Solar energy is no longer just an alternative and has become one of the main solutions for the present and future of the Brazilian electricity matrix.

With more than 39 GW of installed power, advances in technology, job creation and environmental benefits, the photovoltaic sector has played a strategic role in the country's sustainable development.

Whether for homes, businesses, rural properties or public projects, adopting solar energy represents savings, energy autonomy and a commitment to the environment. Despite the challenges that still exist, the scenario is promising — and those who are informed and invest in planning will come out ahead.

If you want to continue learning about how solar energy can transform your consumption and your future, access the Canal Solar and follow the most complete, updated and reliable content on the photovoltaic sector in Brazil.