## 1 Introduction  
In Korea, the demand for heating varies greatly depending on the season, but the heat-to-electricity ratio of cogeneration cannot be adjusted according to the fluctuations of demand [1]. The problem becomes particularly serious during summer when there is no demand for heating; thus, a system configuration and operation plan to solve this problem has been studied. Recently, technologies to reduce heat load in summer, such as green roofs, have been introduced [2]; however, in the case of combined heat and power systems, the treatment of excess heat is still a problem. The most representative approach is the implementation of the cooling system driven by thermal energy [3]. Cooling systems driven by thermal energy include absorption, desiccant and adsorption cooling. In absorption cooling, the technology is highly mature, which might explain its wide usage compared to the other two. To facilitate it, a high-temperature heat source and a large facility are required; thus,it is difficult to use it in connection with an existing district heating system [1; 3]. Desiccant cooling follows absorption in terms of usage popularity. Solid and liquid desiccants are typically used in this system, with more preference is given to the solid one due to technical issues [4; 5]. Additionally, desiccant cooling is sensitive to outdoor air conditions, because dehumidification and ventilation take place during the process [6]. Thus, hybrid desiccant cooling systems are sometimes used to secure sufficient cooling capacity in high-temperature and high-humidity environments, such as Korea or Taiwan [5; 6]. Hybrid desiccant cooling can be considered even in places where applying evaporative cooling is difficult due to insufficient water [7]. When applied in conjunction with district heating, the hybrid desiccant cooling system shows adequate performance, as demonstrated in Korean residential spaces [8]. However, compared with the conventional air conditioners with high technological maturity, the reduced operating costs are deflected by the high costs of equipment, making it difficult to obtain the economics [9]. Because desiccant cooling contributes to energy and greenhouse gas reduction, a common effort by manufacturers, governments, and consumers is required to secure economic feasibility. Manufacturers must reduce costs through technology development. For the government's policy support, a cost-benefit analysis of desiccant cooling in terms of energy and environment should be conducted [10]. In addition, if the effect of improving indoor air quality through desiccant cooling is properly promoted, it can persuade consumers to pay additional costs [11]. Many factors affect indoor air quality; however, in the case of air conditioners, thermal comfort has a great influence on consumers' choices. Among the evaluation indicators of thermal comfort, the simplest and most widely used one is setting the seasonal comfort zone based on temperature and humidity [12]. This is the ASHRAE comfort zone, an indicator developed in the United States. In Japan, which has a similar summer climate to Korea, a result of feeling a little cold in the comfort zone has been reported [13]. However, if the thermal comfort is evaluated using this index, the comparison would be difficult because both conventional air conditioners and desiccant cooling are included in the comfort area [8; 13]. A representative index that allows a relative comparison is the predicted mean vote (PMV) [14; 15]. PMV additionally considers variables such as radiant temperature, metabolic activity, and clothing, among others, in addition to the temperature and humidity of an indoor space. The PMV value ranges from \(-3\) to \(3\), enabling a comparison of the values of relative thermal comfort. However, in PMV, variables such as climate, psychological factors and ventilation are not reflected, which leads to some controversy [16]. Nevertheless, PMV is still the most widely used index for evaluating thermal comfort, along with the ASHRAE comfort zone.