Authors: Carine Tondo Alves, Jadiel dos Santos Pereira and Luciano Sergio Hocevar
Energy Review, Vol 4. Issue 2. 2022
Brazil is currently experiencing a moment of energy insecurity, resulting from a crisis scenario that has dragged on for years and is similar to that which occurred in the 2000s. The reduction of rainy periods has been identified as the main factor of this risk due to its influence on the hydroelectric reservoirs, but would this be the key factor for the possible energy “blackout” of energy in Brazil? Is the scenario likely in the current context of the country, if we consider, in addition to technical and economic aspects, the decisions that were taken? This article seeks to explore the aforementioned issue.
According to the Brazilian National Energy Balance (2021), the national supply of electricity is 645,9 TWh, and the Brazilian electricity matrix is composed of 85% renewable energies, among which hydroelectric power is responsible for 65%, biomass and wind power with 9% each and solar photovoltaic with less than 2%.
Renewable energies such as biomass, wind and solar photovoltaic are increasing rapidly and are very important for the diversification of the Brazilian electric matrix. However, together those represent less than 20% of the all-generated energy. Hydroelectric generation remains predominant, although its share has decreased from 85% in 1980 to 65% in 2021. Hydroelectric energy is advantageous in terms of generation cost, which is lower compared to the other types of energy generation. However, it is heavily dependent on rainfall, which can make the Brazilian electricity production and transmission system vulnerable, especially in periods of lack of rain, when the volume of reservoirs decreases and the electric energy generation started to be carried out by thermoelectric plants. It is during these periods that the possible “blackout” scenario intensifies, as in 2001 and today at the beginning of 2022.
To better understand what differentiates the two scenarios (2001 and 2021), two twenty-year periods (1980-2000) and (2000-2020) were compared. In 1980, Brazil's installed electricity generation capacity was 33 GW. In 2000, it reached 74 GW and then increased to 175 GW in 2020. The Brazilian population was 121 million in 1980, increased to 175 million in 2000 and reached 213 million in 2020. When these data were compared, it was possible to verify that between 1980 and 2000, the installed capacity increased by 124%, while the population grew by 44%. In the period between 2000 and 2020, the installed capacity increased by 137%, while the population increased by 22%. Therefore, it is clear that there is a growth in electricity supply greater than that of the population. This growth is in line with the national energy balance (2021), where the domestic supply of electricity is 645.9 TWh and the final consumption is 540.2 TWh.
Over the twenty years that separate these two events, many assertive decisions were taken, such as investments to increase the installed capacity and diversification of the energy matrix, including wind and solar photovoltaic generation. Management and planning tools were developed and improved, such as the precipitation databases from the National Institute for Space Research (INPE), electricity generation and demand from the National Electric System Operator (ONS) and the National Interconnected System (SIN).
In the possible scenario of blackout in 2022, these databases and software are available for energy planning and its information. Reservoir storage data and rainfall history were already known and were available in 2020 with reports indicating the possibility of water shortages. Therefore, the decision to activate the thermoelectric plants could have been taken before the situation became critical with high operating costs. Historical data from 1981 to 2020 show that between April and October, the monthly rainfall index is low, indicating that the level of reservoirs may decrease, recommending the use of thermoelectric plants.
These data have been important for energy planning without serious problems for twenty years, even with the economy demanding more energy. Therefore, the planning at those times was well executed. Some decisions since the “blackout” in 2001 can be questioned, such as the permission for the increase of deforested and burnt areas, which, in addition to interfering with the flow of rivers, reduced the carbon capture credits in that area. According to the INPE, the Amazon has lost 729,000 km2 to deforestation so far, which means 17% of its entire biome of 300,000 km2 since 2001.
This affects the sources of rivers and alters the rainfall regime. Rivers still suffer from gigantic irrigation projects that benefit few and bring negative environmental consequences for everyone. Some large rivers are dying and the country needs to recognize that this scenario will be bad for its population, as water is good for everyone, not a raw material for a few people who change location, or country, when it is scarce. Furthermore, with the predominance of the hydroelectric model, the electric power generation capacity will be severely affected.
Due to the economic crisis that the country is going through, it is unlikely that a “blackout” will occur and that the energy demand will increase in the short term. Based on this, there is time to correct what is necessary. However, it is possible to observe our total dependence on hydroelectric power and rainfall, as well as on fossil fuels that fuel thermoelectric plants.
The increased production of renewable energy will solve only a small part of the problem of electric generation in Brazil. This country is extensive, populous, with unequal distribution of consumption, different sources of energy generation, storage, dispatch, different intermittence and seasonality, at the moment and in the quantity demanded, and that is why this equation is complex to be solved. Energy planning was, is and will continue to be important, as well as the decisions taken from it, fundamental for the country's energy supply and for the technical, economic and managerial aspects that must always be analyzed together.
(Carine Tondo Alves is an Associate Professor of Energy Engineering department at CETENS, Luciano Sergio Hocevar is a Professor of Energy Engineering department at CETENS, and Jadiel dos Santos Pereira is a Professor, at the Federal University of Reconcavo da Bahia – UFRB, Brazil.)■□■