By Laju Iren

Although there might be some variations across board, many Nigerians sum up the country’s problems in three words: Power, power and power. At the height of the recent fuel crisis, even multinationals and financial giants considered reducing their office hours to save power.

Although in the long term, there are hopes for increased power generation, improved power transmission and distribution services, as well as alternative sources of energy, experts say that making efforts to save energy could be an immediate as well as a long term solution to the power situation.

Emerging Heating Ventilation and Air Conditioning, HVAC, technologies are making it more and more possible to maintain energy efficient and healthy buildings to save power. This formed the crux of the recent public lecture hosted by the Department of Building, University of Lagos, UNILAG.

Head of the Department, Prof. Godwin Idoro said at the event that the issue of energy should without any doubt be a topical one and serious concern for every Nigerian because of the incessant power shortage being experienced daily. His words: “The power supply situation has got to a stage whereby darkness is almost becoming a norm everywhere. The challenges posed by the power supply problem are enormous.

There are several options to look at in facing these challenges namely: increase power generation output, improved power transmission and distribution services, energy saving culture and energy efficient buildings.” His words: “On energy saving or energy efficient buildings, institutions of higher learning and private bodies should emphasize this discipline in their training and development programmes.

Energy efficient approach should be holistic covering design, construction and the use of buildings should emphasize natural rather than artificial lighting and ventilation.” It was however, Professor Chandra Sekhar of the National University of Singapore who, based on his wealth of experience in this area, did justice to the lecture in his role as Guest Speaker, presenting different energy efficient HVAC systems that the Nigerian populace can take advantage of.

One of the options Sekhar mentioned is the Dedicated Outdoor Air System, DOAS,   a HVAC system which consists of two parallel systems: a dedicated outdoor air ventilation system that handles latent loads and a parallel system to handle sensible loads. Another energy efficient method mentioned by Sekhar is the Single Coil Twin Fan Unit, SCTF.

According to him, “the Single Coil Twin Fan system is an innovative air-conditioning and air distribution system that improves occupants’ thermal comfort and indoor air quality in tropical buildings whilst significantly saving energy.   Energy is conserved because the fresh air fan and the re-circulated cooling air fan are controlled independently to optimize their respective airflow requirements based on the individual, localized demand for ventilation or cooling.”

The use of the Single Coil Twin Fan, which combines the use of Air Handling Units with Heat Pipes can possibly lead to improved air quality, thermal comfort and humidity control. The Personalized Ventilation System, also introduced to the audience by Singaporean Professor, makes it possible for air to be delivered directly to the occupant’s breathing zone.

This is done by integrating a desk mounted Personalized Ventilation system with a ceiling supply Mechanical Ventilation system. His words: “This not only saves energy, but the air being ventilated is the right quality. Ventilation effectiveness is also not a problem as clear evidence shows that test subjects find the air acceptable.”