EXHIBITION “ENERGY AND TRANSFORMATION”
“In nature, nothing is created, nothing is lost, everything is transformed”
Antoine-Laurent de Lavoisier, 1785
The history of energy is the energy of history. The transformations driven by energy in cities, especially in São Paulo, with influence on urban space, technologies and people’s daily lives, are part of this exhibition.
In the rooms of the museum upper floor, we will present: the first marks of urbanity in the capital of São Paulo, in the nineteenth century, from gas lighting; the transformations with the arrival of electric and tram street lighting; the large São Paulo mills and their impacts on the landscape from the 1950s; and the everyday life and the exponential increase of energy use in the domestic environment. And we also propose a reflection: how are the use and management of energy and water thought today? And more importantly, how can we ensure equal access for all people to such essential resources?
Finally, the exhibition ends in the “Energy Space”, an educational room that takes a playful approach to its relationship with physics, chemistry and biology. Thus, inspired by the natural sciences, we return to the initial idea: the revolutionary power of this resource. After all, according to its physical principle of conservation, energy can be transformed or transferred, but never created or destroyed.
For much of the 19th century, there was very little street lighting in the city of São Paulo. In 1840, the government of the then Province of São Paulo ordered the installation of 101 fish oil lamps. The start of the public lighting services saw a constant change of concessionaires and experimentation with different fuels. The night of January 6, 1872 marked greater stability in this type of service, when the first gas lamps were lit experimentally by the San Paulo Gas Company. The official inauguration took place on March 31 of the same year, in the presence of King Pedro II, at the Government Palace (Pátio do Colégio) and at Largo da Sé, on the north side of what is now Praça da Sé. Also in 1872, 550 lamps were installed in the streets of the central region and, in 1880, the first residence in São Paulo was illuminated with electric light in Rua Florêncio de Abreu. Lighting was concentrated in the “old town”, while the rest of the city remained dark. In 1883, almost 2,000 people paid for tickets to see the big news: the inauguration of gas lighting in Jardim da Luz. The poles remained in the park until 1933. The new lamps, characterized by their grace and elegance, contributed to the modernization of the São Paulo landscape.
THE FIRST POWER PLANTS FOR POWER GENERATION
In the late nineteenth century, the wealth brought by the production and sale of coffee began to be invested outside the agricultural activity, stimulating the creation of a business culture of farmers, traders and financiers that expanded to an incipient industrial sector, technology, until then, new in Brazil: electricity. This elite wanted to enjoy the benefits of modernity and began to build power plants where they lived.
However, the difficulties for its generation and transmission caused the first São Paulo plants, installed in the interior, to meet a local demand, such as supplying a factory or city. In general, hydroelectric plants took advantage of the force of some waterfall or waterfall already close to the end consumer to produce energy.
| The pioneering plants were almost experimental, with implementation difficulties, such as the import of parts, the establishment of transmission lines, and problems after construction, that is, operation, with reports of fires, flooding and occupational accidents. |
In this context, the first São Paulo hydroelectric power plant was the Votorantim fabric factory, installed in the Sorocaba River, in the homonymous city, in 1892. In the same factory, a thermal power plant had been established in 1889, the first source of driving force for the Votorantim company, in addition to being the plant that inaugurated the generation of electricity in the State. A year later, in São Carlos, the Monjolinho Hydroelectric Plant was inaugurated on June 2, 1893. The third hydroelectric power plant in São Paulo was the Corumbataí Power Plant, in Rio Claro, in 1895. Since 1999, Corumbataí belongs to the Energy and Sanitation Foundation, and is the oldest preserved in the State.
In the 1910s, the trend of generation internalization strengthened, with the beginning of the creation of a more integrated system of generation, transmission and distribution of energy. The choice to use hydroelectric power was intensified by the First World War (1914-1918) and the difficulties in importing the coal used in thermoelectric plants.
THE PARNAÍBA PLANT
he first large hydroelectric plant in the state of São Paulo was the Parnaíba Plant, inaugurated on September 23, 1901. Built by the Anglo-Canadian São Paulo Tramway, Light and Power Company, Parnaíba is still part of the Greater São Paulo hydroelectric system today, under the name of Edgard de Souza Dam.
The site chosen for the power station was Cachoeira do Inferno, a natural waterfall on the River Tietê, in the municipality of Santana de Parnaíba. With frenetic and very advanced works for the time, construction lasted 20 months.
After construction, the Parnaíba Power Station transmitted power to the Paula Souza substation in central São Paulo, which fed the streetcar network, public lighting and other consumers, such as factories. The power provided was approximately 2 megawatts.
THE EXPANSION OF PARNAÍBA AND THE ITUPARARANGA POWER STATION
In 1906, Light built the Guarapiranga Dam, to the south of the city, in what is now the Santo Amaro region, with the aim of regulating the flow of the River Tietê and thus increasing the power generation capacity of the Parnaíba Power Station. In this way, the waters of the dam, via Pinheiros River, would enter the Tietê, increasing the volume of water for Parnaíba’s energy production.
As the demand for energy in São Paulo continued to grow exponentially and the possibility of expanding the Parnaíba Plant was exhausted, a second hydroelectric plant was built in São Paulo by Light, at Salto do Itupararanga, on the Sorocaba River.
The Itupararanga Power Plant is located in the municipality of Votorantim (SP). Construction began in 1911 and it was inaugurated on May 26, 1914.
ELECTRIC STREET LIGHTING
In the city of São Paulo, public lighting using electricity began in December 1888, by Empresa Paulista de Eletricidade, using a coal-fired thermoelectric generator, which ran from dusk until night and lit up the streets of the old town.
Since its inauguration in 1901, the Parnaíba Power Station has brought about a major transformation in the supply of energy in the city of São Paulo, with its large-scale use, as well as being one of the main factors in the industrial leap taken by the capital during the first 20 years of the 20th century.
In 1906, power company Light signed a private contract with traders in Rua Barão de Itapetininga, in the República area, to light up the street in order to attract customers at night. In 1911, the company signed the first contract with the City Government for lighting on Brigadeiro Luís Antônio and Higienópolis Avenues, on Estrada da Penha (now Celso Garcia Avenue), on the streets of the Penha and Lapa neighborhoods, as well as reinforcing Paulista Avenue, which until then had been supplied by gas lamps. In 1929, the municipality transferred the city’s entire public lighting service to Light. The various models of cast iron streetlight poles that would be installed in São Paulo date from this period, the 1930s. Some of these poles are still present in downtown São Paulo today.
| In 1935, the number of electric lamps on the capital’s streets reached almost 15,000. Today, there are more than 600,000 points of light. |
ELECTRIC STREETCARS AND PUBLIC TRANSPORT
Before the electric streetcars, public transportation in the city of São Paulo was carried out by animal-drawn streetcars (donkeys), which began operating in 1872.
In 1899, with the arrival of Light, the city began to receive the works for the introduction of electric trams, such as the implementation of rails and aerial networks. To start the service, the power company built a thermoelectric plant, located at Rua São Caetano. The inauguration of these trams took place on May 7, 1900. The first line had as destination the neighborhood of Barra Funda. At the time, it was said that Light worked to “replace the strength of the donkeys’ blood with the strength of river water”.
By the end of 1900, there were 9 lines, a fleet of 25 trams, 24 kilometers of built rails, 32 motorists (drivers) and 40 drivers (collectors). Thus, the electric tram was the main service offered by Light in the first two decades of the twentieth century. In numbers, in the first year 3 million and 400 thousand passengers were transported.
| HOW ABOUT THE WATER? In the city of São Paulo, already in 1903, there were reports of pollution of the Tietê River waters, due to the dumping of untreated sewage along its course. The “effects of progress” were already perceived in the landscape and rivers of São Paulo when the Anhangabaú Stream was channeled, whose works were completed in 1906. In the 1910s, studies for the water supply of the Cotia River were initiated, and in 1918 the Morro Grande Water Treatment Plant of the Alto Cotia System was inaugurated. |
THE TRANSFORMATIONS IN THE LANDSCAPE
The changes in the landscape of the city of São Paulo, initiated late in the nineteenth century, accelerated in the first decades of the twentieth century, especially in the 1930s. In this period, changes in urban planning began to be implemented, such as the Avenues Plan of mayor and urbanist Prestes Maia and the expansion of public transport, in addition to the increase of private sector investment in the industry.
The São Paulo of contradictions sheltered the coexistence between the new and the old. There were many cities in one – a quiet one, in areas further from downtown, with traditional buildings and transport, provincial daily life and little comfort; another quite busy, in the downtown area, where commercial activities were concentrated, offices, public administration and leisure options. And, still, a city beyond the railways, of difficult access, dispersed in the north, east and south direction, occupied by factories, popular houses and slums, built in the lower and wet lands of the floodplains.
In a short time, the capital registered a huge population growth. In this period, the city gained an air of metropolis, expanding the occupied areas. Over the decades, the urban spot has surpassed the Tietê (to the north), Pinheiros (to the west) and Aricanduva (to the east) Rives, reaching the vicinity of the Guarapiranga and Billings dams (to the south).
| It is also necessary to point out, at the time, the differences in the way of living: while the middle and upper classes imitated European patterns of behavior and living, the working class lived almost colonial, adapted to the emerging working-class villages and urban civilizing patterns. The contradiction also occurred in the fact that the workers of modern and urban functions did not generally enjoy the new comforts of the city. |
Population in the city of São Paulo
1872 – 30 thousand
1900 – 240 thousand
1920 – 500 thousand
1940 – 1.3 million
1950 – 2 million
THE 1920S AND THE WATER CRISIS
Between 1924 and 1925, São Paulo experienced its first energy crisis, caused by an intense drought that reduced the flow of the Tietê and Sorocaba Rivers by around 40% and the supply of electricity by almost 70%.
The water crisis highlighted the lack of long-term planning for energy production. In addition to the prolonged drought, the Paulista Revolt of 1924 caused serious disruption to the capital’s energy supply.
There was also an increase in demand due to the rapid growth of industry, both manufacturing and agricultural, powered by electricity. The inevitable consequence was rationing. Also inevitable was criticism of Light, the company responsible at the time for generating, transmitting and distributing electricity and the services that depended on them.
RASGÃO PLANT
As a consequence of the water crisis, there was rationing, and the electricity supply to industries was reduced to five hours a day. Light’s employees were also directly affected, with mass layoffs. The population was alarmed.
Faced with the crisis, the company used two tactics. The first was to increase the maximum capacity of the existing power generating units, such as the Itupararanga Plant, which received an additional turbine, resulting in an increase of 19 megawatts of energy. And the second was the construction of new hydroelectric plants, then considered large-scale, such as the Rasgão Plant and the Cubatão Plant (Serra Project).
Work at the Rasgão plant, located on the Tietê River in the Pirapora do Bom Jesus region, began in October 1924 and was completed just 11 months later, in September 1925. The end of rationing in the capital was declared a few days after the inauguration of the plant’s second generating unit. With an installed capacity of 22 megawatts, the new hydroelectric plant had two transmission lines that carried the energy generated to the Parnaíba Power Plant.
THE SERRA DO MAR PROJECT
The most important project started in the 1920s, however, was Light’s Serra do Mar project, which allowed for the reversal of the course of the Pinheiros River, the expropriation of land and the construction of new dams and reservoirs, in order to enable the implementation of a large hydroelectric complex.
Audacious and controversial, the project was led by the American engineer Asa W. K. Billings. Considered at the time to be one of the largest in the world, the new hydroelectric plant in the Serra do Mar, in Cubatão, ensured the development of the entire industrial park in São Paulo and the urbanization of the capital and regions in the interior of the State, as well as being a determining factor in the deployment of the industrial hub of Cubatão (SP). The landscape of São Paulo capital was irreversibly altered, as was the course of its main rivers.
In addition to the Cubatão Hydroelectric Plant, now Henry Borden, the project included a system of dams, reservoirs (Rio das Pedras, Billings and Pirapora), pumping stations, canals, tunnels and pipelines.
| HOW ABOUT THE WATER? In the 1920s, the Tietê River Improvement Commission was organized, headed by sanitary engineer Saturnino de Brito. The aim of the Commission was to prevent flooding and promote the urbanization of the São Paulo capital’s floodplains, to allow the navigation in stretches of the river, and to prevent the discharge of untreated sewage. In order to meet the growing demand for water for public supply, in 1928 the Commission abandoned the criterion of “protected waters”. This enabled the government to obtain authorization to draw four cubic meters of water per second from the Guarapiranga Dam. This is an important milestone, given that until then the 196 million cubic meter reservoir had been used exclusively for electricity generation. Another important project started during this period was the Rio Claro water supply, one of the four public supply systems that still serve the capital today. |
THE BIG POWER PLANTS
After World War II (1939-1945), industrialization boomed, with a new cycle of steel plants being set up in the country, such as those in Volta Redonda and Cubatão, and the installation of metallurgical plants in the ABC region of São Paulo. As a result, there was an increase in the demand for electricity, far greater than the supply. This led to an energy crisis, resulting in rationing in the Interior of the state of São Paulo.
In the early 1950s, the crisis was aggravated by an intense drought, reducing the level of hydroelectric reservoirs by around 60%. Between 1953 and 1955, “blackouts” were common in the city of São Paulo, lasting between 5 and 7 hours a day.
In 1952, Light started the construction of the Piratininga Thermoelectric Plant, on the banks of the Pinheiros Canal, near the Billings Dam. The thermoelectric plant was inaugurated on November 15, 1954, celebrating the IV Centenary of the City of São Paulo.
At the time, it was considered the largest thermoelectric plant in Latin America.
The inability of Light to meet the demand for electricity led the São Paulo government to enter the sector directly creating, in 1953, the Usinas Elétricas do Paranapanema (USELPA), the first mixed economy company in the energy area. In 1961, another state-owned company emerged: Centrais Elétricas de Urubupungá (CELUSA). In 1966, the power companies of the São Paulo government, in addition to small private concessionaires, were unified into Centrais Elétricas de São Paulo (CESP). The set of these state-owned companies was responsible for the construction of the main large plants existing today in São Paulo.
It is from this time the construction of the Urubupungá Complex, which includes the Jupiá and Ilha Solteira plants. Both represented the doubling of energy produced within a radius of 700 km, reaching 50 million inhabitants in five Brazilian states. During this period, Brazil had already evolved in knowledge and technologies, and the presence of foreign technicians and engineers was no longer necessary for the projection and installation of a large hydroelectric power plant.
Under the slogan “50 years in 5”, the federal government of Juscelino Kubitschek (1956-1960) created a goals plan in which investment in infrastructure construction occupied a central role, with the energy sector being one of its priorities. In the governments of Jânio Quadros and João Goulart (1961-1964), the creation of Eletrobrás was approved in order to assume the planning functions of the electricity sector.
Years later, the expansion of power generation, with the construction of large hydroelectric plants, was intensified during the early period of the Military Dictatorship (1964-1985).
The large hydroelectric power plants were considered essential to the economic project of the current regime and its consequent legitimation.
Another element that contributed to the increase in plant construction was a series of studies of hydroelectric potential in the Southeast Region, aiming at a long-term planning of the sector.
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Investments in the 1970s were mostly concentrated in power generation, and resources for transmission and distribution were limited, which resulted in serious sectoral and regional imbalances. In the 1980s, resources were channeled to the Itaipu and Tucuruí hydroelectric projects and to the nuclear power plants in Angra dos Reis.
SÃO PAULO POWER PLANTS
The Capivara Power Plant is the largest in the Paranapanema River, and began operations on March 10, 1977. Located between Taciba (SP) and Porecatu (PR), it has the largest water reservoir along the river, with more than 609 km² of area and 10.5 billion m³ of dams, which contributes to the control of flooding in the region.
Located in Rio Paraná, the Ilha Solteira Plant was inaugurated on January 10, 1974. It is the largest plant in the state and has an installed capacity of 3,444 thousand MW. It represents a major milestone in the history of hydroelectric plants in the country, because it is a project of gigantic proportions and the use of new construction techniques.
Três Irmãos is the largest dam on the Tietê River. Located between Andradina (SP) and Pereira Barreto (SP), it was inaugurated in 1991. It has two locks that enable navigation between the Paranapaíba, Paraná and Tietê rivers, in addition to assisting in the control of floods, both the Tietê Waterway and the Paraná Waterway.
Porto Primavera has the most extensive dam in Brazil, with more than 10 thousand meters in length, and is located in the Paraná River, in the municipality of Rosana (SP), formed by the confluence of the Paranaíba and Grande rivers.
The works for the plant construction began in 1980, being paralyzed in 1983, due to the economic recession, and resumed in 1992. The first stage of the installation of Porto Primavera was completed in 1999, when the first three generating units were connected, 19 years after the beginning of its works.
THE ENVIRONMENTAL ISSUE
Hydroelectric power plants generate energy in a clean way and at low cost, compared to other sources, for having as main raw material the water of the rivers. Among other advantages are the use of its structures for different purposes, such as irrigation, flood control and navigation.
However, its construction also causes negative environmental and social impacts, such as deforestation, disappearance of animal species, change in the river regime, and demographic changes in the territory. We have to bear in mind that, in Brazil, the first environmental law is from 1981 and that these issues were not debated by society until then.
CHANGES IN THE HOME ENVIRONMENT
From the 1940s, some transformations became noticeable within the homes of the Brazilian elite: the rationalization of internal spaces, with new plants that restricted the social sector of the house, limited to a room connected directly to the kitchen or a winter garden, in addition to the use of new household appliances, in general imported.
Generally speaking, In the 1950s there was the progressive replacement of fresh food with packaged and industrialized food; home-made clothes were replaced by ready-made clothes; and the use of electric showers and gas heaters became popular. The spread of the use of electric lighting and various appliances happened in such a way that many of them became increasingly essential.
POPULARIZATION OF HOUSEHOLD APPLIANCES
Thus, from the 1950s onwards, household appliances entered Brazilian homes for good, although by the upper and middle classes. The increase in consumption was made possible by the start of domestic production, which made prices cheaper, and by the expansion of credit in the 1960s.
The new consumer market was driven by companies that sold energy and by manufacturers of major household appliances. At the beginning of their popularization, advertising focused on the benefits of appliances in the domestic routine.
The advertising campaigns, which publicized the advantages of the new appliances, reinforced the stereotype of the domestic space as the sphere of women’s work par excellence. This illustrated woman, with white hands, delicate fingers and preserved skin, demonstrated the racial and social targeting of the advertisements: white women, housewives, mothers and those with greater purchasing power.
At the beginning of the 1950s, the problems of poor sanitation still persisted in the city of São Paulo, but they were mitigated by a series of works and new structures. Today, access to water and sewage collection in the capital has been universalized, while the rate of treated sewage is around 70% of the water consumed.
1959 – Inauguration of the Vila Leopoldina Sewage Treatment Plant.
1972 – Inauguration of the Pinheiros Sewage Treatment Plant
1973 – Creation of the Basic Sanitation Company of the State of São Paulo (SABESP), with the aim of planning, executing and operating basic sanitation in the state of São Paulo.
1974 – Start of operation of the new Cantareira Water Supply System.
1988 – Inauguration of the Barueri Sewage Treatment Plant, the largest in South America.
1992 – Start of operation of the Alto Tietê Water Supply System
POSSIBLE CITIES
Nowadays, new solutions for water and energy management are linked to the concept of “smart cities”, which refers to the changes in urban experiences that citizens can have, especially related to the use of new technologies in city infrastructure. It also covers access to education, work, leisure and health facilities that provide social cohesion.
However, part of the population still does not have access to basic and essential resources. Although data show that almost 100% of the population of São Paulo has access to electricity, we need to keep in mind the concept of energy poverty. That is, real physical access to modern energy services – their use for thermal comfort (fan or air-conditioning), food conservation (refrigerator, refrigerator or freezer), information and/or leisure (computer and television) and domestic services (washing machine) –, in addition to lack of access in informal settlements and financial difficulties in paying energy bills.
This is a major challenge for public management. In the case of organized civil society, we find institutions that work with innovations and technological solutions designed and realized to enable access to water and electricity.
WATER AND SEWAGE
Population without access to water
33,211,937
Population without sewage collection
92,871,315
Annual hospitalizations for waterborne disease
128,912
Source: Brazilian Sanitation Panel, 2021
ELECTRIC POWER SUPPLY
Homes without access to electricity
141,000
Population without electricity in the Legal Amazon
990,000
Indigenous lands without access to electricity
19%
Source: PNAD, 2019 and IEMA, 2021
More than 50% of the world’s population lives in urban areas, which are responsible for 75% of the energy consumed in the world. This same urban layer is responsible for 80% of carbon dioxide emissions. Industry for the generation of heat and electricity is responsible for 3/5 of these emissions.
The so-called energy transition encompasses the generation, consumption and reuse of energy, and envisages the migration from polluting energy matrices – such as fossil fuels based on coal or oil – to renewable or alternative energy sources, such as hydroelectric, wind, solar and biomass energy.
Brazil is working with other countries to diversify energy sources so that their production reduces carbon emissions and contributes to sustainable development for the coming decades of population growth.
PRESENT AND FUTURE CHALLENGES
Have access to water and energy means having access to housing. Public policies aimed at electricity and basic sanitation have the challenge of taking into account the social issues of the right to decent housing, a structural problem in Brazilian society. In addition, Brazil has the second most expensive electricity tariff in the world, according to an analysis by the International Energy Agency (IEA).
Another challenge is the global climate emergency. The effects of environmental disasters manifest themselves in a territorially unequal way, disproportionately impacting urban populations, depending on their degree of vulnerability. Therefore, in order to talk about the future of energy and sanitation, we need to take climate change into account, as well as the parts of the population that are most vulnerable to water scarcity, floods, landslides, lack of energy, food insecurity, among others. Patterns of income, level of education, race/skin color, gender and location define who the most vulnerable and impacted populations are.
POWER IN SP
POWER GENERATION
The power installed capacity in Brazil is approximately 195 Giga Watts (GW). This corresponds to the sum of the power of each power generating plant in the country. In other words: what they are capable of producing when working at full capacity together.
SP 25.2 Giga Watts (GW) (12.9%)
Other states 170.1 Giga Watts (GW) (87.1%)
GENERATION BY SOURCES
More than half of São Paulo’s energy matrix is produced from renewable sources.
Hydroelectric plants 60.5%
Biomass power plants 26.4%
Fossil thermoelectric plants 10%
Photovoltaic 3.5%
POWER PLANTS
Although its production is still timid, São Paulo today ranks among the top countries in photovoltaic generation, with a capacity of 894 MW and more than 60 plants installed.
Hydroelectric plants 126
CGH Hydroelectric Generating Plants 56
Small Hydroelectric Power Plants PCH 27
Hydroelectric Plants UHE 43
Thermal power plants 940
Biomass 234
Fossil 704
Photovoltaic 68Wind energy 1
CONSUMPTION
São Paulo has the largest industrial park in Brazil and a high population concentration. As a result, the state consumes more energy than it generates, and has to import an average of 60% of the electricity it needs from other states. This energy is transported through the National Interconnected System.
+ More than 20 million consumer units, including homes, industries, businesses, etc.
+ on average, 25% of the energy generated in Brazil is consumed in the state of São Paulo
CONSUMERS*
Residential 31.6%
Industrial 37.8%
Commercial 20.5%
Rural 1.9%
Public (lighting, services) and other 8.2%
* Average number of consumers in the state of São Paulo in percentages.
Source: Energy data from the São Paulo State Department for the Environment, Infrastructure and Logistics. 2023
THE ENERGY THAT COMES FROM THE “WASTE”
With a view to public health and the environment, waste management in cities must take into account its collection, storage, transportation, treatment, destination and final disposal. One of the alternatives already underway in Brazil is biogas, which generates energy from the decomposition of organic waste of animal, vegetable or industrial origin. Biogas is considered a stable and predictable source of clean energy with low greenhouse gas (GHG) emissions.
The Brazilian Waste Energy Recovery Association (ABREN) points out that the country produces around 82 million tons of waste a year (2021 data). Of this total, 38 million tons are generated in 28 metropolitan regions and could be used to produce electricity, benefiting more than 120 million Brazilians by 2040.
You know those more scientific questions about energy generation, energy matrices and energy sources? This is the Space for you to answer them – and create some other questions! The Energy Space is a bridge between the history and science of energy. Here, you can interact with the panels, test your knowledge of physics concepts in a fun way, learn more about women scientists and get hands-on with the experiments.
Energy can be defined as any body capable of doing work or performing an action. It can be chemical, potential, kinetic, electrical, among others. It is one of the most essential concepts in Physics! Energy also has its particularities in other areas of science, such as biology and chemistry. In nature, we have the sun as one of the greatest sources: its energy heats the planet and transforms itself, providing the emergence and maintenance of life.
ATOM
The atom can be defined as the smallest portion of a chemical element. As such, it is also the smallest structure of matter (that which has mass and volume, and is the fundamental unit of all physical objects). In modern atomic theory, the atom is made up of two regions: the nucleus (protons and neutrons), which holds a positive charge; and, around the nucleus, the negative electric particles, which are known as electrons.
ELECTRON
The electron is a particle present in the structure of the atom. The electron has a negative electrical charge and its continuous movement can generate electrical and thermal energy. Thus, the electron is the protagonist that allows electricity to be generated in hydroelectric power stations, for example. It is also responsible for establishing bonds between atoms of different chemical elements, allowing ionic, metallic and molecular compounds to be formed. Chemical bonds occur through the transfer or sharing of electrons, according to the laws of quantum mechanics.
ELECTROSTATICS
Branch of physics devoted to studying the behavior of electric charges at rest. Examples of this science are lightning and sparks. It can be divided into three branches: Electrostatics by friction (happens when two or more insulating bodies are rubbed against each other); by contact (involves two conducting bodies, at least one of which must be electrically charged) and, finally, by induction (consists of assigning an electric charge to an object using another charged body without there being any contact between them).
POTENTIAL DIFFERENCE
Also known as “ddp”, it represents the work done by the electric force to carry the charge from point “a” to point “b”. This difference can best be seen in a battery, where we have the negative side, with a large number of free electrons, and the positive side, with a low number of electrons. When we connect a wire, nature tries to equalize this potential difference by transporting the excess electrons from the negative to the positive side.
ELECTRIC CURRENT
Electric current is the orderly flow of electric charges moving through a conductive material such as copper, silver or aluminum. It is measured in amperes (A). Electric current is generated when there is a difference in potential (V) between points in a circuit, which causes electrons to move from the point of lowest potential to the point of highest potential. Electric current can be direct, when the flow of electrons is constant in a single direction, or alternating, when its direction is periodically reversed in a cycle.
DIRECT AND ALTERNATING CURRENT
Alternating Current (AC) is a type of electric current that changes direction periodically, i.e., the flow of electrons reverses direction constantly. This type of current can have its voltage regulated by means of transformers, allowing energy to be transmitted over long distances. We can see AC being used, for example, in the large transmission towers we see on roads and highways.
In the case of Direct Current (DC), the flow of electrons follows its path from negative to positive in a single direction, with no alternations in its direction, making it more commonly used in low-voltage circuits, such as batteries or refrigerators.
VOLTS, WATTS and AMPERES
Volts, Watts and Amperes are three units of measurement related to electricity. Watts (W) represent power, which is the capacity of electrical energy to do a work. It is used to measure the consumption of an electrical appliance. Volts (V) are used to measure the difference in electrical potential between two points in a circuit, also known as electrical voltage. Amperes (A), on the other hand, measure the rate of flow in a circuit, i.e., the intensity of the electric current. The voltmeter, wattmeter and ammeter were created to measure these three units in electrical devices.
CONDUCTIVE MATERIALS
Some materials lose electrons more easily than others: this is the case with conductors. If electric current is generated through the orderly movement of electrons, a material that can donate and transfer electrons to other atoms more easily and more frequently is the most suitable for conducting electricity. Copper, for example, is a good conductive material.
A very common conductive material is the metal part of light bulbs, usually made from a mixture of copper and zinc.
Best conductors: silver, gold, copper, aluminum, iron, seawater.
INSULATING MATERIALS
Materials that lose electrons less easily than others are called insulators. Plastics, for example, are more attached to their electrons, offering great opposition to the passage/exchange of electrical charges.
If you look at the streetlight poles, you’ll notice that the power lines are attached to the poles by means of porcelain insulators.
Best insulators: plastic, wood, rubber, porcelain.
MAGNETISM
Magnetism is the property of attraction and repulsion of matter. Although it manifests itself in materials such as magnets and metals, magnetism is present in all matter. The magnetic field is created from the moving charges (the electrons). Thus, it is also possible to create magnetic fields from the electric current (electromagnetism). Earth, for example, is a large natural magnet with a magnetic field and, like any magnet, has two poles: north and south.
ELECTROMAGNETISM
Electromagnetism is a junction of electricity and magnetism. When electricity passes through a wire, the ordered motion of electrons creates a magnetic field around it, as if it were an invisible magnet. And when a magnet moves near a closed circuit, it exerts a force of attraction and repulsion on the moving electrons, creating an electric current inside the wire. This process is very important to allow actions such as turning on a lamp or making a motor work.
ELECTROCHEMISTRY
Electrochemistry is a process in which chemical energy is transformed into electrical energy. This process is very important for the operation of batteries. For this to happen three basic components are needed, two electrodes – the cathode (positive pole) and the anode (negative pole) –, and an electrolyte, which is nothing more than a conductive solution. When we put these three materials together, they interact and generate a chemical reaction. In this reaction, the exchange of electrons occurs between the electrodes: this is the electron movement that generates electricity.
LIGHT ENERGY
Light energy is a type of radiant energy that propagates in the form of electromagnetic waves. The main source of light energy that exists is the Sun, a natural source. But there are also artificial light energy sources (such as lamps, for example). The conversion of light energy into electrical energy is possible through devices called photovoltaics, such as photovoltaic solar cells. When sunlight hits these cells, the electrons present in them shake and their movement is able to generate electricity.
KINETIC ENERGY
Kinetic energy happens when a body is in motion which, due to this fact, also makes it capable of moving or deforming other bodies around it. Think about it: a person is riding a bike, and the speed at which they ride interferes with how fast the bike will move. This relationship between the human body and the bicycle body represents kinetic energy. The junction of kinetic energy with potential energy will result in mechanical energy.
GRAVITATIONAL POTENTIAL ENERGY
This is the form of potential energy that is associated with the height of a body in relation to a region with gravity. It is stored when an object is lifted above the ground. A good example is hydroelectric plants: the gravitational potential energy contained in the water of a high dam is converted into kinetic energy, moving the blades of the plant turbines.
CLEAN ENERGY?
Clean energy is energy that doesn’t release pollutants into the atmosphere and only has an impact on nature where the plant is installed. It comes from renewable sources, such as wind, solar, tidal (tidal movement), geothermal (heat), hydraulic (water), nuclear (nuclear reaction) and biomass (organic matter).
The name “clean” suggests that these sources are free of problems, but the reality is that every form of energy generation has its impacts, however minimal.
RENEWABLE AND NON-RENEWABLE ENERGY
Renewable energy is energy that comes from natural resources (such as the sun, wind and rain) and has the capacity to regenerate itself continuously. It is important to note that not every natural resource is renewable: for example, coal and oil are taken from nature, but they exist in limited quantities. So, they produce energy, but in a non-renewable way, and generate a greater environmental impact than renewable energy sources.
SYSTEM COMPONENTS
For an electrical system to work, different components are needed. What are they? Generator: converts different forms of energy (mechanical, for example) into electrical energy, like a hydroelectric plant. Capacitor: stores electrical energy. It has two terminals, also called armatures: one positive and one negative, like a battery. Receiver: transforms electrical energy into another type of energy, as long as that other type of energy is not heat, like a fan. Transformer: regulates the levels of electrical energy by controlling its voltage. Resistor: reduces the flow of electrons in an electric current and can generate heat, like a shower resistor.
| Thermoelectric Burning fossil fuels to generate energy | Represents 15.4% of the electricity produced in Brazil. In the world, the thermoelectric source is equivalent to 61.1% of the electric matrix. The largest thermoelectric power plant in Brazil is Sergipe I (SE), which uses natural gas. Two power plants like these would be necessary to supply a city like São Paulo. |
| Positive points Low risk of accidents; High energetic potential; Quick construction; Quick power generation; Installation close to cities. | Negative points Non-renewable energy; Produces highly polluting gases, contributing to the greenhouse effect; Produces highly toxic gases for the population; High cost of energy production; Geographical dependence on gas deposits. |
| Wind Uses the winds to generate energy | Represents 13.39% of the electricity produced in Brazil. In the world, wind energy is equivalent to 6% of the electric matrix. The largest Wind Farm in Brazil is Lagoa dos Ventos (MG). It would take two of these parks to supply a city like São Paulo. |
| Positive points Renewable energy; does not emit polluting gases; Takes up little space; Easy Installation; It can be installed onshore or offshore. | Negative points Noise pollution (produces constant noise); Affects the fauna and flora of the region; Accidents with birds and bats; It depends on the winds; Visual pollution. |
| Biomass Burning of organic matter to generate energy. | Represents 8.62% of the electricity produced in Brazil. In the world, the thermoelectric source is equivalent to 2.5% of the electric matrix. The largest plant of its kind in Brazil is the Bracell Thermoelectric Plant, in Lençóis Paulista (SP). It would take 7.6 of these plants to supply a city like São Paulo. |
| Positive points Renewable energy; Low cost; Versatility (can use multiple sources to generate energy); Low level of pollution; Reuse of waste materials. | Negative points Deforestation; Low performance; Contributes to the formation of acid rain; Difficulties in the transport and storage of raw materials; High cost of installation. |
| Solar Uses sunlight to generate energy | Represents 4.47% of the electricity produced in Brazil. In the world, solar energy is equivalent to 3% (photovoltaic) + 0.1% (thermal) of the electric matrix. The largest Solar Farm in Brazil is São Gonçalo (RJ). It would take 3.6 parks like this to supply a city like São Paulo. |
| Positive points Renewable energy; Medium life time of 25 years; Low maintenance; does not emit polluting gases; Takes up little space. | Negative points Deforestation for collection of raw material; Disposal of boards produces a lot of garbage; Affects the fauna and flora of the region; Climatic dependence; Low yield. |
| Nuclear Uses radioactive materials to generate energy. | Represents 1.03% of the electricity produced in Brazil. In the world, the source is equivalent to 10% of the electric matrix. The largest plant of its kind in Brazil is Almirante Álvaro Alberto – Unit II [former Angra II] (RJ) and it would take 2.2 of these plants to supply a city like São Paulo. |
| Positive points Takes up little space; Low emission of polluting gases; Low cost for power generation; Great efficiency. | Negative points Non-renewable; Generation of radioactive waste; High cost of maintenance; Risk of nuclear accidents; High cost of construction. |
| Tidal power Uses tidal power to generate energy. | In Brazil there is only one test plant that generates energy from the tides. In the world, this source represents 0.004% of the electric matrix. In Brazil, still under study, we have the pilot project for a tidal power plant in Porto Pecém (CE). It would take 326 plants like the one designed in Ceará to supply a city like São Paulo. |
| Positive points Renewable energy; Tidal constancy and predictability; Low environmental risk; It does not emit polluting gases. | Negative points High cost of installation; It affects marine life; Geographical limitation; Susceptible to sea storms. |
| Geothermal Uses heat from the Earth’s interior to generate energy | In Brazil there are no such plants. In the world, this source represents 0.4% of the electric matrix. Brazil does not present favorable geographic characteristics (near the edges of tectonic plates) for geothermal generation. |
| Positive points does not emit polluting gases; Low environmental risk; Takes up little space; Stable raw material; Does not attack the soil. | Negative points Non-renewable energy; High cost of installation; Low efficiency; Contributes to generating harmful gases to humans; Geographic dependency. |
Marie Curie was born in 1867, in Poland. At the age of 26, she graduated in physics from the Sorbonne University in Paris and a year later in mathematics.
Years later, during her doctorate, she met scientist Pierre Curie, with whom she ended up marrying.
Fascinated by the glow emitted by the uranium salts, Marie began to study this phenomenon, and called this effect “Radioactivity”. During her work, she discovered two new chemical elements: Polonium and Radio. These studies earned the Curies a Nobel Prize in 1903.
While Marie was studying the properties and therapeutic potential of the radio, she was able to obtain this element in a metallic state. These discoveries brought further recognition to Marie, the Nobel Prize in Chemistry in 1911.
Marie was the first person to receive the award twice. Her studies were very important for various applications of radioactivity, from the use in medicine to the development of Nuclear Power Plants.
Mária Telkes, known as the Queen of the Sun, was born in 1900 in Hungary. At the age of 24, she completed her doctorate in Physical Chemistry and then moved to the United States.
In 1939, she began working on solar energy conversion projects at the Massachusetts Institute of Technology (MIT). During World War II, Mária created a solar distiller that produced drinking water.
After the war, the scientist participated in the development of a house heated with solar energy and in 1953-1954 developed a solar oven.
Irène Joliot-Curie, daughter of Marie, was born in France in 1897.
In 1914, Irène entered the School of Science at the University of Paris, but soon had to interrupt her studies because of the war. At that time, she worked with her mother in the care of the wounded in the conflict, in mobile X-ray units.
After the war, she returned to research at the Curie Institute, where she completed her doctorate on the alpha rays of the element polonium.
During her studies, she met her future husband, scientist Frédéric Joliot, with whom she started working. Together, the two discovered how to artificially create radioactivity, which earned them the Nobel Prize in Chemistry in 1935.
Irène’s discoveries were crucial years later to intensify researches into the transformation of nuclear energy into electricity.
Hypátia was born in Alexandria, Egypt, in the Roman Empire, around 355 AD.
She is considered the first mathematical woman in the world, at a time when the role of woman was restricted to marriage and the care of the home.
Following the footsteps of her father, Theon, director of the Alexandria Museum, she studied astronomy, religion, poetry, the arts, exact sciences, and medicine.
A few years later, she became director of the Alexandria Academy.
Hypátia suffered strong persecution of Christians, for defending reason and science. For these reasons, in 415, returning home, she was attacked and murdered.
Lise Meitner was born in Austria in 1878. She is known to have coined the term Nuclear Fission and explained this important phenomenon.
Nuclear fission is the division of the nucleus of an atom. This reaction produces an enormous amount of energy, being used in the Nuclear Power Plants for the generation of electricity and in the manufacture of atomic bombs.
Although the discovery was very important for nuclear physics, Meitner was never officially recognized. Her working partner published the discovery without mentioning her name and won the Nobel Prize alone.
Eunice Foote was born in 1819 in the United States and pioneered studies on global warming.
She studied at Troy Women’s Seminary, a pioneering school in women’s education, where students had access to science classes and laboratories to further their studies, a rarity for the time.
In 1856, in the annual meeting of the America Association for Science Progress the study authored by her was presented, about the relationship between the increased carbon dioxide (CO₂) in the atmosphere and global heat. Entitled “Circumstances affecting the heat of the sun’s rays,” it is recognized as the first study on global warming.
In addition to her pioneering science, Eunice fought for the civil, social, political and religious rights of women.
Annie Easley was born in 1933 in the United States. In her childhood, she could not study in good schools, as they were reserved only for white people.
Under the influence of her mother, she continued her studies and, at the age of 22, she was hired by NASA as a mathematician and computer engineer.
In the 1970s, due to the oil crisis, NASA began doing research related to alternative forms of energy. That’s when Annie started to develop research with solar energy, wind and electric batteries, to solve energy problems caused by the scarcity of fossil fuels.
Edith Clarke was born in 1883 in the United States. At the age of 25, she graduated in Mathematics and Astronomy. Shortly after, she joined the Civil Engineering course and began working in a telephone and telegraph company. It was around this time that Edith became interested in the field of electricity.
In 1918, she became the first Electrical Engineer in the United States, graduated from the Massachusetts Institute of Technology (MIT).
One of her most important contributions was the “Clark Calculator”, a device that accelerated up to 10 times the calculations related to the distribution of electricity on transmission lines.
Shirley Ann Jackson was born in 1946 in the United States. At the age of 18, she joined the Massachusetts Institute of Technology (MIT), where she earned her PhD in Nuclear Physics.
Shirley became the first African-American woman to earn a doctorate at the institution and the second woman in the country to hold a doctorate in physics.
In the 1970s, she became a visiting scientist at CERN acceleration laboratory, the European Center for Nuclear Research, in Switzerland.
Her work in physics allowed numerous advances, especially in the areas of telecommunications, optical fiber and solar cells.
Sonja Ashauer was born in 1923 in São Paulo. At 19, she graduated in Physics from the University of São Paulo (USP), being the second woman graduated in Physics in the country, alongside Elisa Frota Pessoa, graduated in the same year.
In 1945, she entered the University of Cambridge in England, a country where, by law, women could not receive doctorate and PhD degrees.
But, in 1948, the legislation changed, and Sonja was able to receive the recognition of, at the age of 25, becoming the first Brazilian woman to obtain a Doctorate in Physics, with the thesis “Problems on electrons and electromagnetic radiation”.
She was also the first woman to participate in the Cambridge Philosophical Society.
Sônia Guimarães was born in 1957, in São Paulo. At the age of 22, she graduated in Physics from the University of São Carlos (UFSCar), a career she followed until 1989, when she completed her PhD in Electronic Materials from the Institute of Science and Technology, University of Manchester, England, becoming the first black woman with PhD in physics.
Years later, she joined as a professor at the Technological Institute of Aeronautics (ITA), being the first black professor of the institution, a space that, until 1996, did not allow female students.
Sônia specializes in semiconductors, raw material used in the manufacture of chips for various electronic devices, such as smartphones, video games and computers.
“In elementary school, I was told that I would never learn physics.”
Elisa Frota Pessoa was born in Rio de Janeiro, in 1922. At the age of 20, she graduated in Physics from the University of São Paulo (USP), being, alongside Sonja Ashauer, the second woman graduated in this course in the country.
In 1949, she was one of the founders of the Brazilian Center for Physical Research (CBPF).
Elisa was responsible for introducing the nuclear emulsion technique in Brazil. This technique, called “Particle Detectors”, was very important to understand, from radiation, how subatomic particles behave, in the field of nuclear physics, biology and elementary particles.
In 1955, her article, “A new Radioactive method for markings mosquitoes and its application”, in collaboration with Mário Aragão and Neusa Margem, was the only Brazilian work selected for the International Conference of Atoms for Peace, debates in favor of nuclear disarmament.
Throughout her career, Elisa has worked at leading universities in Brazil, the United States and Europe.
Enedina Marques was born in 1913, in Curitiba (PR).
In 1940, she joined the Civil Engineering course of the Federal University of Paraná (UFPR), a class formed only by white men. Being a black woman of poor origin, she suffered various forms of prejudice and discrimination. In 1945, she became the first black woman to graduate as an Engineer in Brazil.
Shortly after, she was called to work in the State Department of Water and Electricity of Paraná. Working directly in the Paraná Hydroelectric Plan, she contributed to several projects in the state’s rivers, especially in the Capivari-Cachoeira Plant, the largest underground hydroelectric plant in the south of the country.
Márcia Barbosa was born in 1960 in Rio de Janeiro. At 21, she graduated in Physics from the Federal University of Rio Grande do Sul (UFRGS), where years later she obtained her PhD. She is also a postdoctoral fellow in physics at Boston University and the University of Maryland.
Marcia studies water anomalies. In other words, how and why water interacts with the environment in a different way than most elements we know.
A practical application of her findings is a method of desalination of sea water by means of tubes 60 times thinner than a hair. Innovation that can help bring clean water to people who do not have access to this so important resource.
Recently, Márcia was elected one of the 20 most powerful women in Brazil, in a ranking where, until then, no scientist had been honored, and also entered the list of the United Nations (UN) as one of the “Seven scientists who shaped the world”.
Thelma Krug was born in 1951 in São Paulo. At the age of 24, she graduated in mathematics from the University of Roosevelt in the United States.
Years later, she completed her doctorate in Space Statistics at the University of Sheffield in England.
Thelma worked for 37 years at the National Institute for Space Research (INPE), where she was head of the Remote Sensing Division. INPE is an internationally recognized institute when it comes to deforestation and climate change.
Since 2015, she has been Vice-President of the UN Intergovernmental Panel on Climate Change (IPCC). The role of the IPCC is to study climate change and make scientific assessments, and with this data to understand the impacts of these changes and the possible risks to the planet today and in the future.
Thelma is considered worldwide as one of the leading authorities in climate change and forests.
Nadia Ayad was born in 1994 in Rio de Janeiro. At the age of 20, she graduated in Metallurgical Engineering from the Military Engineering Institute (IME). In the same year, she won the global competition “Graphene Challenge”, created by the Swedish company Sandvik Coromant, which seeks sustainable and innovative solutions.
Nadia’s project consists of a filtering mechanism and a water desalination system, which makes it drinkable from the use of graphene.
Graphene is a raw material composed of carbon atoms, 200 times stronger than steel, but extremely thin and a great conductor of electricity.
In 2017, Nadia joined the PhD in Bioengineering at the University of California in the United States.
Viviane dos Santos Barbosa was born in 1975, in Bahia. She studied Industrial Chemistry for two years at the Federal University of Bahia (UFBA), but in the 1990s decided to move to the Netherlands and study Biochemistry and Chemical Engineering at the Technical University of Delft. A few years later, she became a master in Nanotechnology at the same institution.
At that time, Viviane was researching catalysts, substances that improve and accelerate the yield of chemical reactions. The catalysts developed by it can be used in reducing the emission of polluting gases, as well as in the development of alternative energies and for environmental control.
This research earned her, in 2010, the first place in the International Aerosol Conference, a meeting that brought together 800 researchers in Finland.
“I’ve always been very curious and wanted to understand why about everything.”
Elisama Vieira was born in 1987 in Japi, Rio Grande do Norte.
At the age of 22, she graduated in Chemistry at the University of Rio Grande do Norte (UFRN). Years later, she graduated with a doctorate at UFRN in partnership with the University of Castilla-La Mancha in Spain.
In her doctorate, she studied the application of electrochemical treatments for the decontamination of soils and waters by leakage of petroleum by-products and heavy metals. In addition, Elisama studies renewable energies, such as solar and wind, and ways to make these generation processes cheaper, so they can be used on a large scale.
For these studies and for her performance in environmental protection sciences, in 2016, she received the “For Women in Science” award from UNESCO, the Brazilian Academy of Sciences and L’Oréal. In 2020, Elisama was also awarded the Elsevier Award for Green Electrochemistry from the International Society of Electrochemistry.
The Energy and Sanitation Foundation and the Energy Museums
The Energy and Sanitization Foundation is a living memory and exists to inspire people about the importance of water and energy for life. It works by developing cultural and educational projects that contribute to the democratization of access to cultural heritage, aiming at strengthening citizenship and the responsible use of natural resources.
The Energy Museum of Itu is installed in a townhouse built in 1847 and located in the historic center of the city. In its rooms, the visitor makes a journey back in time, knowing how people’s daily lives have changed along with the arrival of energy.
Installed in a park formed by remnants of the Atlantic Forest, the Energy Museum of Salesópolis has a hydroelectric power plant inaugurated in 1913. The space offers educational and cultural activities, with guided visits and trails, dealing with issues about energy and the environment.
Did you enjoy your visit? Follow the activities of the Energy Museum of São Paulo (@museudaenergia).