An increase in relative humidity of air downstream of cooling coils is a natural result of energy transfer.

The statement is accurate because an increase in relative humidity downstream of cooling coils is a common consequence of the process of cooling air. When air passes over cooling coils in a system, it is typically cooled to lower its temperature, which can lead to moisture condensing out of the air if the temperature drops below the dew point. However, even though the air is cooled, if the air is supplied with additional moisture during the cooling process (which can happen in various HVAC systems), the relative humidity can increase.

The cooling process involves energy transfer, where heat is removed from the air, but it can also involve the transfer of moisture if there is no proper management of air exchange or dehumidification. In commercial systems, the complexities of managing air flow and humidity levels can lead to increased relative humidity if not properly controlled, but this does not mean that the phenomenon is limited to commercial applications. The same concept applies in residential systems as well.

Thus, the statement holds true because it describes a fundamental aspect of how air conditioning and cooling systems work, highlighting the interplay of temperature and moisture in relation to energy transfer.