Potential of using EAHX for low energy cooling in Nigeria

Earth-air heat exchangers (EAHX), also called ground tube heat exchangers, are a possible technique to reduce energy consumption for heating or cooling in buildings. The growing pressure for low energy and environmentally-sensitive building is likely to continue alongside the desire to have more efficient facilities management. Therefore there is need for greater interaction at the organization level between facilities management providers and designers to close the gap between philosophies. The hot dry climatic zone of Nigeria is characterized by a period of high temperature and low relative humidity between February and May. Between these months, the daily mean maximum indoor temperature of most buildings is about 37ºC with low indoor air velocity. Most occupants of the buildings in Nigeria have persistent and growing problems with the indoor environment due to high indoor temperature. Also they are characterized by poor design in relation to the climate, which requires a great deal of energy for cooling during climatic extremes. Other problems are poor natural ventilation, inadequate surface – volume ratio and poor building orientation. This has led to negative consequence that affect the occupant’s physiological comfort, capacity for mental and physical work, health and leisure. This research identifies technology that can be adopted in this climatic region to minimize the use of energy for cooling, improve occupant’s comfort and enhance low energy. The objective is to reduce overdependence on electricity demand and energy use in residential buildings in Nigeria.