Brazil indicated a commitment of reducing greenhouse gas emissions at the Paris Conference in 2015, which has led the Brazilian government to incentivise the use of renewable energy sources. Biomass is a renewable energy source that can be used to produce electricity, with its availability mainly connected to the sugar and alcohol sector in Brazil. The study presented herein applied the life cycle assessment methodology to the generation of electricity from sugarcane bagasse and from diesel in thermoelectric power plants, and verified the potential to mitigate climate change. The production of electricity from sugarcane bagasse presented a low carbon footprint (0.227 kg CO

The development and implementation of public policies towards renewable energies are crucial in order to address the contemporary challenges faced by humanity. The 3Rs (reduce, reuse, and recycle), as a circular economic practice, are often cited as one of the best solutions for sustainable development. Therefore, this study analyzed public policies for renewable energy from the perspective of the circular economy. Accordingly, a systematic review of the literature was carried out with respect to the beneficiaries and convergences of circularities, with a focus on public policies for renewable energies. The sample had public policies classified into three types (distributive, redistributive, and regulatory policies). The results showed that the first studies began in 1999, with a significant increase in publications during the 2010s, in which Germany was the country with the greatest contribution. The analyses associated with space showed the countries committed to the use of renewable energies and the 3Rs of the circular economy to reduce greenhouse gas emissions. The economic analyses revealed that the circular economy for the generation of renewable energy has a positive economic return in terms of social well-being and the mitigation of environmental degradation. There is a barrier to the circular economy’s development posed by the cost of its implementation in the private sector and the resistance to raising awareness in society, requiring strong public sector engagement in decision making and the constant evaluation of public policies. It is concluded that the circular economy facilitates more efficient, productive structures and public policies, promoting alternatives for energy security and sustainability for the world energy matrix.

A Área de Preservação Permanente (APP), principal área protegida instituída por norma jurídica no Brasil, foi criada pelo Código Florestal (Lei 4.771) em 1965. Por sua importância ecológica e fornecimento de bens e serviços ambientais ao homem, as APPs são reconhecidas por suas funções técnicas como áreas que devem ser preservadas. Muitas interpretações divergem do espírito da criação da Lei, seja pelo preciosismo linguístico ou pelo uso distorcido da hermenêutica O objetivo desta pesquisa foi analisar os principais pontos conflituosos do entendimento, da interpretação e da instituição das Áreas de Preservação Permanente. Concluiu-se que há, na literatura, pertinentes interpretações contrárias ao espírito da norma jurídica que institui as APPs; as APPs devem ser preservadas e, em caso de degradação, a legislação deixa patente que o passivo ambiental deve ser sanado; a intocabilidade das APPs não é inexorável, pois o CONAMA, em alguns casos, pode definir critérios para sua utilização; as intervenções em APP, permitidas por lei nos casos de utilidade pública, interesse social e atividade eventual e de baixo impacto ambiental necessitam de melhor regulamentação.

In the energy supply and conversion system proposed herein, the following energy demands were considered for a hospital: electricity, sanitary hot water, steam, and cooling. A superstructure representing all options of equipment and energy resources was built, with conventional equipment as well as more complex technologies, such as absorption chillers and cogeneration modules. Two renewable energy resources were available: solar photovoltaic energy and biomass (sugarcane bagasse). The solution of a mathematical model based on mixed integer linear programming provided the optimal economic solution, constituted by the configuration of the system (equipment installed) and its operation strategy (how to operate each equipment, throughout one operational year). The objective function considered the minimisation of total annual costs, which encompassed fixed costs (equipment) and variable costs (maintenance and energy costs). A reference system was designed, where only conventional equipment was utilised (no cogeneration, no solar or biomass utilities available). The optimal economic solution included the utilisation of biomass to produce hot water and steam, with an annual cost that was 11% lower than the reference solution. Although the economic optimal solution did not install cogeneration modules, it took advantage of solar and biomass resources to achieve annual minimum cost.