Author: Simon Herzog
Energy Review, Vol 5. Issue 06. 2023
Only a few countries, like Brazil, provide such favorable conditions for renewable power generation. South America's largest country is blessed with almost complementary sources of wind, sun, and hydropower. Hydropower is currently the most important pillar, with a share of around two-thirds in annual electricity production. Wind and photovoltaic solar power are fast-growing contributors. In 2011, the installed capacity of wind turbines reached 1 Gigawatt (GW); ten years later, it exceeded 20 GW. The growth of photovoltaics was even faster. In 2017, the total power of all solar panels reached 1 GW. In 2023, just six years later, more than 30 GW of photovoltaics were connected to the grid.
This impressive growth is likely to continue for many years. Germany, for example, is more than 20 times smaller than Brazil and a much less sunny country. However, per capita photovoltaic installations are above 800 W in Germany, whereas in Brazil, they are only around 150 W. Solar power is an optimal pillar for Brazilian electricity supply since it covers the growing demand caused by air conditioning. Moreover, energy from the sun helps during droughts, where hydropower operates at its limits.
Another massive driver of electricity demand is still at its beginning: The production of green hydrogen. Green hydrogen will be needed for the decarbonization for a wide range of industrial processes, such as the production of steel and fertilizer. But the smallest molecule will also be an energy carrier for long-term storage, heavy-duty, and long-distance transport, e.g., ships and aircraft. Globally, multi-million tons of green hydrogen are needed in the future as a substitute for natural gas and other fossil fuels. For this gigantic hydrogen production by electrolyzers, additional gigantic amounts of renewable power sources must come. Brazil has the potential to host a large share of them. Many Brazilian players prepare themselves so that the country covers an essential part of the value creation chain for green hydrogen.
Since wind and photovoltaic power will likely be the main contributors to the Brazilian electricity mix, one might ask if there is enough land for wind farms and solar parks. One outcome of my research was estimating the area needed depending on different demand scenarios, including a large-scale production of green hydrogen. The basis for the scenario analysis was a linear-optimization model with a high temporal resolution, considering regional differences of demand and supply within the macro-regions of Brazil. As an output, the model delivered power generation and storage capacities to cover the assumed electricity demand at minimal costs. Derived from the necessary generation capacities, I calculated roughly the space needed for installing wind turbines and photovoltaic arrays. The figures show the simplified results of these calculations displayed on the map of Brazil.
Since the Northeast hosts some of the best locations of Brazil for harvesting wind and solar energy, and for the sake of simplicity, all generation capacity is concentrated there. Naturally, and as an outcome of the model, the generation capacity is distributed nationwide. Different input data characterizes each scenario. The most important variations are prizes for fuel to feed conventional plants and prizes for stationary batteries. Above all, the total demand varies by scenario. One essential driver of the electricity demand is the production of green hydrogen. The areas for wind farms and photovoltaic (PV) arrays depicted on the maps show the annual values of electricity production by wind and sun specifically, but also the total electricity production, including existing hydropower. One must remember that Brazil's total electricity, including all citizens, industry consumers, and businesses, summed up to around 600 TWh per year.
In contrast, the most conservative scenario assumes an almost doubled demand of 1.100 TWh. This scenario is named on the map 1a-F4B1, with the most minor space need of around 90 km by 90 km. The most extreme scenario displayed here is S2-F2B4, which assumes a fourfold increase in electricity demand compared to recent years. The additional demand originates mainly from green hydrogen production. If 1.000 TWh of electricity is converted into 660 TWh of hydrogen, 20 million tons can be produced. Around 600 TWh equals Germany’s natural gas imports from Russia before the war with Ukraine. In other words, Brazil could evolve to produce green hydrogen in the same magnitude as Russia for natural gas.
The most remarkable outcome is the comparison of the space needed for the most extreme scenario in comparison to the recent acreage for sugar cane. On around 50.000 km², sugarcane is cultivated for fuel production, delivering 160 TWh of ethanol. To make it comparable, all the Brazilian cropland for sugarcane is concentrated into the depicted square with a length of approximately 220 km. The area for the most extreme scenario, producing 1.800 TWh of wind and solar electricity, is 210 km by 210 km, even smaller than the current acreage for sugarcane.
With the set of meteorological, spatial, economic, and political conditions, the largest country in South America offers among the best preconditions on the planet to be one of the big players in green hydrogen. The journey has already begun. Brazil is paving the way to be a global leader in green hydrogen.
(Dr Simon Herzog is a senior project leader at the Technical University of Munich (TUM). These thoughts are an extract of a joint project conducted at the Universidade Estadual de Campinas (UNICAMP), São Paulo, Brazil and TUM.) ■□■