Circular economy and sustainability are pivotal concepts in the discourse on the synergies between economic growth and environmental impact. As resource scarcity and environmental degradation intensify, advancements in energy conversion technologies become crucial for a sustainable economic model. Currently dependent on fossil fuels, the global economy must shift to a sustainable framework focused on bioenergy. Biomass, a renewable energy source, offers a promising solution by converting waste into valuable resources, reducing waste and environmental impact, and creating economic opportunities. Biofuels and bioproducts can meet energy needs while reducing greenhouse gas emissions and addressing global warming. Recent advances in biofuels, supported by initiatives and policies, promote more sustainable energy production. This paper aims to highlight the potential of biomass in meeting contemporary energy demand and provides an overview of biofuels and their production as a renewable alternative to fossil fuels. It also explores the future of agriculture and energy sectors, emphasizing global energy and environmental challenges and the competition between food and fuel feedstocks.

An economy based on renewable energy sources is the hallmark of responsible companies. Climate policy and energy crisis commitments have led to a search for alternative ways to produce energy. Bioenergy is considered the most consistent renewable energy source due to its economic and environmental benefits. Biogas and biomethane are promising forms of renewable energy derived from widely available evergreen raw materials. Agricultural, animal, industrial and food wastes are excellent substrates used to produce clean and sustainable energy in a circular economy context. Their conversion into biogas and biomethane through the anaerobic digestion (AD) process is an efficient solution to the treatment of waste of different origins. The production and use of biomethane favor important environmental advantages, such as the reduction in greenhouse gas emissions compared with those deriving from the use of conventional fossil fuels. This review would like to highlight modern trends and approaches to evaluate processes and strategies to control biogas and biomethane production. In particular, the use of livestock waste for the digestion process and the reuse of the by-product as fertilizer, as well as the potential development of biogas and biomethane as prospects for the improvement and optimization of renewable energy sources, are discussed.

This contribution aims to provide an in-depth outlook of the phase-out of coal-fired energy generation in Italy. In particular, this article analyzes the state-of-the-art with regard to both the current role of coal generation and the performance of the main legal and regulatory tools as implemented in Italy thus far to ensure the closure of all coal power plants by 2025 as announced in the Italian National Climate and Energy Plan. Based on existing data and scenarios on both electricity production and demand trends, this article unfolds the marginal role played by coal-fired generation in the Italian energy mix. In addition, this paper aims to highlight the outstanding technical uncertainties and regulatory hurdles in the way towards de-carbonization of energy generation in Italy. This paper argues that several remarkable improvements are needed in order to avoid over-generation (especially through natural gas), to upscale the penetration of renewable energy sources, and develop the necessary infrastructures to adequately deliver on the full phasing-out of coal within the expected timeframes.

Among all the emerging contaminants, fragrances are gaining more relevance for their proven allergenic and, in some cases, endocrine-disrupting properties. To date, little information exists on their concentration in the air. This study aims to fill this gap by developing a method for the determination of semivolatile fragrances in the indoor gaseous phase with sampling protocols usually adopted for the collection of atmospheric particulate matter (sampling time 24 h, flow rate 10 L min⁻¹) and instrumental analysis by gas chromatography coupled with mass spectrometry. The method was developed on 66 analytes and tested at three concentration levels: 20 compounds showed analytical recoveries ≥72% with percentage standard deviations always better than 20%. For most compounds, negligible sampling breakthroughs were observed. The method was then applied to real samples collected in a coffee bar and in a private house. Considering the fragrances for which the method has shown good effectiveness, the highest concentrations were observed for carvone in the coffee bar (349 ng m⁻³) and camphor in the house (157 ng m⁻³). As concerns certain or suspected endocrine disruptors, lilyal and galaxolide were detected at both sites, α-isomethylionone was the second most concentrated compound in the house (63.2 ng m⁻³), musk xylene and musk ketone were present at lower concentration (≈ 1 or 2 ng m⁻³).

In Italy, the de-carbonization process descending from the National Energy Strategy (NES) of the November 2017 and the National Energy and Climate Plans (NECPs) of December 2019 has led two specific effects: the progressive ending of coal use as a fuel for the production of electricity and the emanation of authorization acts for the conversion to natural gas of existing coal-fired power plants and/or for the construction of new power plants powered by natural gas. These new plants will be technologically advanced and designed to guarantee the safety of the national electricity grid in periods of greatest energy demand and will have to support the growing part of energy produced with plants powered by renewable energy sources (especially wind and photovoltaic). This reference context will necessarily have to take into account the recent gas supply difficulties due to the Russian-Ukrainian conflict, which could lead to a reconsideration of the projects for the construction of new gas plants by focusing on other energy sources. This paper hence aims to quantify and to evaluate the effective environmental benefits for atmospheric emissions, related to the replacement of coal with natural gas. Starting from the electrical powers replaced and installed, the potential reductions in greenhouse gas emissions will be examined, comparing the current emission situation in terms of CO₂, with the future scenarios deriving from the construction of thermoelectric plants whose projects are currently under authorization.

Atmospheric pollution is an important task in life sciences and, in particular, inorganic fraction characterization is considered as an important issue in this field. For many years, researchers have focused their attention on the particulate matter fraction below 10 μm: in this case, our attention was also focused on PM_2.5 (i.e., particles with a size fraction smaller than 2.5 μm) and PM₁ (below 1 μm). This paper would like to investigate whether the element accumulation in different granulometric fractions is similar, or whether there are behavior dissimilarities. Among the different analytical techniques, the instrumental neutron activation analysis, an instrumental nuclear method, was used for its peculiarity of investigating the sample without performing any chemical-physical treatment. Forty-two daily samples using the reference method were collected, 15 filters for PM₁₀, 18 for PM_2.5, and 12 for PM₁; the filters, along with primary standards and appropriate standard reference materials, were irradiated at the National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) R.C.-Casaccia’s Triga MARK II reactor. The irradiations carried out in the Rabbit and Lazy Susan channels allowed for the investigation of 36 elements and the relative Pearson’s correlations between elements and PM-fractions (PM₁₀ vs. PM_2.5 was good, whereas PM₁₀ vs. PM₁ was the worst). The Enrichment Factors were studied for the three fractions to show how anthropogenic sources have affected the element content. A comparison between these data and element levels determined worldwide showed that our concentrations were lower than those determined in similar scenarios. Furthermore, a statistical approach (source discrimination, hierarchical cluster analysis, principal component analysis) has allowed us to identify similarities between the samples: the airborne filters can be divided in two main groups (i.e., one made of PM₁₀ and PM_2.5 filters and one only of PM₁ filters), meaning a different element contribution to this fraction coming from other sources present at the site.