Plants may have several impacts, which can be categorized into indoor air quality, energy use, and psychological effects. This thesis presented a comprehensive review of the impact of indoor plants in these categories. Indoor plants can emit a negligible amount of VOCs and microorganisms to the indoors but also have limited ability to remove pollutants. In addition, greenery systems are exterior to the building enclosure, resulting in a reduction of external surface temperature and heat transfer, particularly in certain climates. Interaction with indoor plants can also deliver measurable psychological benefits to people despite the confounding variables and other experimental design issues. In conclusion, indoor plants have limited effect on indoor air quality, external plants have a possible impact on saving energy, and indoor plants can influence psychological status when placed on the level of vision. Plants cannot be treated as a system, and other alternatives can provide promising solutions

Human comfort is the main goal of the different air conditioning systems. In modern systems, the radiant panels are used in rooms, because they produce a low noise levels and the required equipment are few. In this thesis, two types of radiant panels were used; an electric heating panel was used in a scale room model for heating process, while radiant cooling panels with cooling coils were used in a typical full scale room for cooling process. The rooms were vacant. The two processes were studied experimentally and numerically. A numerical model was also employed to study flow pattern inside the rooms and to predict temperature distributions. The flow field was obtained by solving the flow governing equations for continuity, momentum and energy equations. The turbulent flow was solved by using Re-Normalization Group RNG k-ε turbulent model. Heat transfer by radiation was modeled by using Discrete Ordinates DO radiation model. The results showed that the used numerical technique could accurately predict the temperature distribution in the scale room model. In heating process, the effects of heating panel surface area, heating panel locations, and heating panel surface temperatures on air temperature distributions, air motion, and heat transfer were studied. In cooling process, two configurations of radiant panels were tested experimentally and studied numerically. A third configuration of radiant panel was proposed. The effect of radiant cooling panel surface area, boundary conditions of radiant panels, and outside conditions on air temperature distributions, air motion, and heat transfer were studied. The conclusions are that the radiant panel systems achieved thermal comfort.