Background BNT162b2 mRNA and ChAdOx1 nCOV-19 adenoviral vector vaccines have been rapidly rolled out in the UK from December, 2020. We aimed to determine the factors associated with vaccine coverage for both vaccines and documented the vaccine effectiveness of the BNT162b2 mRNA vaccine in a cohort of health-care workers undergoing regular asymptomatic testing. MethodsThe SIREN study is a prospective cohort study among staff (aged ≥18 years) working in publicly-funded hospitals in the UK. Participants were assigned into either the positive cohort (antibody positive or history of infection [indicated by previous positivity of antibody or PCR tests]) or the negative cohort (antibody negative with no previous positive test) at the beginning of the follow-up period. Baseline risk factors were collected at enrolment, symptom status was collected every 2 weeks, and vaccination status was collected through linkage to the National Immunisations Management System and questionnaires. Participants had fortnightly asymptomatic SARS-CoV-2 PCR testing and monthly antibody testing, and all tests (including symptomatic testing) outside SIREN were captured. Data cutoff for this analysis was Feb 5, 2021. The follow-up period was Dec 7, 2020, to Feb 5, 2021. The primary outcomes were vaccinated participants (binary ever vacinated variable; indicated by at least one vaccine dose recorded by at least one of the two vaccination data sources) for the vaccine coverage analysis and SARS-CoV-2 infection confirmed by a PCR test for the vaccine effectiveness analysis. We did a mixed-effect logistic regression analysis to identify factors associated with vaccine coverage. We used a piecewise exponential hazard mixed-effects model (shared frailty-type model) using a Poisson distribution to calculate hazard ratios to compare time-to-infection in unvaccinated and vaccinated participants and estimate the impact of the BNT162b2 vaccine on all PCR-positive infections (asymptomatic and symptomatic). This study is registered with ISRCTN, number ISRCTN11041050, and is ongoing.Findings 23 324 participants from 104 sites (all in England) met the inclusion criteria for this analysis and were enrolled. Included participants had a median age of 46•1 years (IQR 36•0-54•1) and 19 692 (84%) were female; 8203 (35%) were assigned to the positive cohort at the start of the analysis period, and 15 121 (65%) assigned to the negative cohort. Total follow-up time was 2 calendar months and 1 106 905 person-days (396 318 vaccinated and 710 587 unvaccinated). Vaccine coverage was 89% on Feb 5, 2021, 94% of whom had BNT162b2 vaccine. Significantly lower coverage was associated with previous infection, gender, age, ethnicity, job role, and Index of Multiple Deprivation score. During follow-up, there were 977 new infections in the unvaccinated cohort, an incidence density of 14 infections per 10 000 person-days; the vaccinated cohort had 71 new infections 21 days or more after their first dose (incidence density of eight infections per 10 000 person-days) and nine infecti...

Summary The implementation of mobility restrictions and home office schemes due to the COVID‐19 pandemic have influenced electricity consumption patterns and levels. This study analyzes the effect of physical distancing measures regarding mobility on the energy consumption trends for the Brazilian energy system and its subsystems (Northeast, North, South, and Southeast‐Midwest). Trends were evaluated by the Joinpoint software, and the analysis comprehended the period between January 1 and May 27, 2020. Daily load data was grouped into weeks, with the calculation of weekly percentage changes considering a 95% confidence interval and p < 0.05. The weekly electricity loads were compared in the periods before and after the isolation decrees were enforced in Brazil (March 15, 2020). Statistically significant decreases were observed in the levels of electricity consumption, with trends represented by two joinpoints. Due to the different profiles of consumption across the geographic regions, the resulting electricity dynamics were also different. This is the first study to employ joinpoint analysis for the calculation of energy consumption trends focusing on the COVID‐29 pandemic. Data presented herein is unique, in its focus on Brazil, which enables more accurate implications to be drawn for Brazilian policy makers.

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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.

A energia solar fotovoltaica dentro da geração distribuída vem se consolidando no Brasil desde 2012. Este crescimento é acompanhado por um desconhecimento dos efeitos, tanto técnicos quanto ambientais, da utilização deste recurso no Sistema Elétrico Brasileiro. O primeiro passo deste estudo foi aplicar a metodologia daAvaliação do Ciclo de Vida a todas as etapas do Sistema Elétrico Brasileiro, para quantificar as emissões associadas ao consumo de 1 kWh de eletricidade no Brasil. O potencial de geração foi considerado, juntamente com as seguintes etapas (e consequentes perdas) associadas à transmissão, distribuição e transformação. Os documentos de referência utilizados para as projeções de geração de eletricidade foram os relatórios anuais estatísticos da Empresa de Pesquisa Energética e do Plano Decenal de Expansão da Eletricidade 2024. Os mixes elétricos para os anos de 2001, 2006 a 2015 e 2024 foram modelados no software SimaPro, para todas as etapas do Sistema Elétrico Brasileiro. O método de avaliação de impacto ambiental selecionado foi o IPCC 2013 GWP 100a, que expressou os resultados da análise em termos de kg de CO2-eq. Uma contribuição importante deste estudo, que será utilizada em estudos de otimização do fornecimento energia com o software Lingo, é o estabelecimento da dinâmica das emissões associadas ao consumo de eletricidade no Brasil. O potencial da eletricidade solar fotovoltaica para substituir a geração termoelétrica foi verificado. Em 2015, a eletricidade solar fotovoltaica apareceu na matriz elétrica brasileira e, após análise de representatividade para o ano 2024, foi identificada uma potencial redução na pegada de carbono do mix de eletricidade brasileiro a partir deste ano. Embora a eletricidade solar fotovoltaica apresente alto potencial de mitigação de mudanças climáticas, ainda é inexpressiva e não apresenta potencial para substituir as usinas termelétricas na matriz elétrica brasileira. Resumen La energía solar fotovoltaica dentro de la generación distribuida se ha consolidado en Brasil desde 2012. Este crecimiento se acompaña de un desconocimiento de los efectos, tanto técnicos como ambientales, de la utilización de este recurso en el Sistema Eléctrico Brasileño. El primer paso de este estudio ha sido aplicar la metodología del Análisis de Ciclo de Vida a todas las etapas del Sistema Eléctrico Brasileño para cuantificar las emisiones asociadas al consumo de 1 kWh de electricidad en Brasil. Se ha considerado el potencial de generación, y las etapas siguientes (y consecuentes pérdidas) asociadas a transmisión, distribución y transformación. Los documentos de referencia utilizados para las proyecciones de generación de electricidad han sido los informes estadísticos anuales de la Compania de Investigación Energética y el Plan Decenal de Expansión de la Electricidad 2024. Los mixes eléctricos para los años 2001, 2006 a 2015 y 2024 fueron modelados en el softwareSimaPro, para todas las etapas del Sistema Eléctrico Brasileño. El método de evaluación de impacto ambiental seleccionado ha sido el IPCC 2013 GWP 100a, que expresa los resultados del análisis en términos de kg de CO2-eq. Una importante contribución de este estudio, que se utilizará en estudios de optimización del suministro de energía con el software Lingo, es el establecimiento de la dinámica de emisiones asociada al consumo de electricidad en Brasil. El potencial de la electricidad solar fotovoltaica para sustituir generación termoeléctrica también ha sido verificado. En 2015 la electricidad solar fotovoltaica apareció en la matriz eléctrica brasileña, y después del análisis de representatividad para el año, se identificó una potencial reducción en la huella de carbono de la mezcla eléctrica brasileña después de este año. Aunque la energía solar fotovoltaica presenta un alto potencial de mitigación de cambio climático, sigue siendo inexpresiva y no presenta potencial para sustituir las centrales termoeléctricas en la matriz eléctrica brasileña. Abstract Photovoltaic solar energy within distributed generation has been consolidating itself in Brazil since 2012. This growth is accompanied by a lack of knowledge of the effects, both technical and environmental, of the utilization of this resource in the Brazilian Electric Power System. The first step of this study applied the Life Cycle Assessment methodology to all stages of the Brazilian Electric Power System, to quantify the emissions associated with the consumption of 1 kWh of electricity in Brazil. The generation potential was considered, along with the following steps (and consequent losses) associated with transmission, distribution and transformation. The reference documents utilized for the electricity generation projections were the statistical annual reports of the Energy Research Company and the Decennial Plan for Electricity Expansion 2024 (published by the Energy and Mines Ministry). The Brazilian electricity mixes for the years 2001, 2006 to 2015 and 2024 were modeled in SimaPro (LCA software), for all stages of the Brazilian Electric Power System. The environmental impact assessment method selected was IPCC 2013 GWP 100a, which expressed the LCA results in terms of kg CO2-eq. An important contribution of this study, and that will be further utilized within energy supply optimization studies with software Lingo, is the establishment of the dynamics of emissions associated with the consumption of electricity in Brazil. In 2015 photovoltaic solar electricity appeared in the Brazilian electricity matrix, and after representativeness analysis for year 2024, a reduction was identified in the carbon footprint of the Brazilian electricity mix after this year. Although photovoltaic solar electricity presents high potential for climate change mitigation, it is still inexpressive and does not present potential to substitute thermoelectric power plants in the Brazilian electricity matrix.

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Besides satisfying the energy demands of buildings, distributed generation can contribute toward environmental conservation. However, determining the best configuration and operational strategy for these systems is a complex task due to the available technology options and the dynamic operating conditions of buildings and their surroundings. This work addressed the synthesis and optimization of an energy system for a commercial building (hotel). Electricity, hot water, and cooling demands were established for a hotel located in Northeast Brazil. The optimization problem was based on mixed-integer linear programming and included conventional equipment, solar energy resource (photovoltaic and thermal technologies), and biomass. The objective function of the optimization was to minimize annual economic costs, which involved considering the capital and operation costs. A reference system was established for comparison purposes, where energy demands were met conventionally (without cogeneration or renewable energy), whose annual cost was BRL 80,799. Although the optimal solution did not rely on cogeneration, it benefited from the high degree of energy integration and had a total annual cost of BRL 24,358 (70% lower). The optimal solution suggested the installation of 70 photovoltaic panels and used biomass (sugarcane bagasse) to operate a hot water boiler. Solar collectors for hot water production were not part of the optimal solution. Sensitivity analyses were also carried out, varying the electricity and natural gas tariffs, and the type of biomass employed, but the configuration of the system did not change compared with the optimal economic solution.