Abstract The aim of the present research was to propose a bioclimatic mapping to classify the thermal comfort and discomfort of rural workers within the state of Minas Gerais, considering historical and future scenarios. Monthly historical series (1976-2014) of minimum, mean and maximum temperature-humidity index (THI), determined through the values of air temperature (minimum, mean and maximum) and relative humidity from 48 weather stations located in the state of Minas Gerais were used to analyze the trends through Mann-Kendall and linear regression assays. The bioclimatic mapping of human comfort, obtained via geostatistical analysis, was developed as a function of the minimum, medium and maximum THI for the historical period (1976-2014) and future scenario (2024). Results indicate an overall trend of increasing in thermal discomfort conditions throughout the mesoregions of the state of Minas Gerais during the weather seasons, being more incisive in summer and spring.

RESUMO A produção de frangos de corte é altamente dependente do uso de luz artificial. O custo do consumo de energia elétrica do sistema de iluminação artificial constitui a segunda maior despesa relacionada à produção de frangos de corte, inferior apenas às despesas com ração. Portanto, objetivou-se com o presente trabalho analisar a viabilidade técnico-econômica de se substituir a lâmpada incandescente utilizada nos aviários por outros tipos de lâmpada. O consumo de energia e os custos de implantação e de manutenção dos sistemas de iluminação foram avaliados com auxílio da matemática financeira, por meio do valor presente líquido, da taxa de retorno do investimento e do tempo de retorno do capital (payback). Foram avaliados sistemas compostos por seis tipos de lâmpada, em duas configurações diferentes, para atender às iluminâncias mínimas de 5 e 20 lux e para a utilização em galpões convencionais e dark house. As lâmpadas testadas foram a incandescente (LI) de 100 W, a fluorescente compacta (LFC) de 34 W, a mista (LM) de 160 W, o vapor de sódio (LVS) de 70 W, a fluorescente tubular T8 (LFT T8) de 40 W e a fluorescente tubular T5 (LFT T5) de 28 W. Para os sistemas testados, verificou-se que as lâmpadas fluorescentes tubulares T8 e T5 apresentaram os melhores resultados de viabilidade técnica e econômica.

ABSTRACT Broiler poultry is highly dependent on artificial lightening. Power consumption costs of artificial lighting systems is the second largest expense related to broiler industry, second only to feed expenses. Therefore, the current study focused to analyze technical and economic feasibility of replacing incandescent lamps already used in aviaries with other lamp types. Costs related to power consumption, implementation and maintenance of the lighting systems were evaluated with the aid of financial mathematics using net present value, return over investment and payback. Systems composed of six lamp types were analyzed in two different configurations to meet the minimum illuminance of 5 and 20 lux and for use in conventional sheds and dark house. The lamps tested were incandescent (LI) of 100 W, compact fluorescent (CFL) of 34 W, mixed (ML) 160 W sodium vapor (SVL) of 70 W, tubular fluorescent T8 (TFL T8) of 40 W and tubular fluorescent T5 (TFL T5) of 28 W. For the systems tested, it was found that the tubular fluorescent lamps T8 and T5 showed the best results of technical and economic feasibility.