Steelmaking is a key-sector for development; it is also one of the most energy and CO₂ intensive industries. Brazilian steelmaking was responsible for 44.3 million metric tons of CO₂ emissions and 40% of its output supported the international steel demand in 2018. Then, there is a need to harmonize the increasing steel demand with low carbon energy alternatives towards sustainable development. Here, we forecast scenarios until 2050 to analyze the CO₂ reduction potential through energy transitions in two production routes of the Brazilian steelmaking: for primary steel, the increase of renewable charcoal use in blast furnaces; and for secondary steel, whose direct emission is relatively low but it is highly power intensive, the use of on-site photovoltaic (PV) energy to meet the power demand. Renewable energy sources for electricity play a particularly relevant role as power demand increases 69% with the substitution of charcoal for coke. The analysis has been supported by econometric models and emission factors from the IPCC GHG inventory guidelines for direct and indirect emissions. Results have shown that steel production will increase 1.8% per year from 2020 levels and will yield 77MtCO₂ in 2050. The Charcoal+PV scenario can mitigate 49% of such emissions. The land-intensity to enable such scenario is 51m² per avoided tCO₂ for the entire period. Alternatively, if steel sector’s emissions were compensated by native reforestation, this value decreases to 38m²/tCO₂. However, according to the uncertainty analysis, reforestation presents a higher land-intensity than charcoal+PV scenario in 31% of the Monte Carlo simulations. In addition, other issues affect suitability of the scenarios and must be discussed: the benefit-cost of bioenergy versus costs of conservational reforestation; ancillary benefits of standing forests such as biodiversity improvement. Moreover, considering the carbon cycle, charcoal is sustainable far beyond the analyzed period, whereas new areas will be needed to stock carbon in conservational reforestation projects. The findings of this study can assist governmental and private decision-makers to elaborate policies for more plausible pathways to confront climate change and guarantee economic, social, and environmental development.