Jose Franco talks to Varun Pahwa of Desiccant Rotors International to get the low-down on the latest developments in energy-recovery systems.

With today’s moves towards cost reduction, energy conservation, building eco-friendly structures and improving indoor air quality (IAQ), energy recovery has never been more appealing. In fact, any new applied technology related to this technique or method of minimising the input of energy to an overall system may cause a breakthrough in the world of IAQ.

Take, for instance, the Dedicated Outdoor Air Systems (DOAS), which DRI (Desiccant Rotors International), a sister company of US-based desiccant humidification firm, Bry-Air, launched recently. With its “unique combination of special rotors and cooling coil”, Varun Pahwa, Executive Vice-President of DRI, says DOAS facilitates the energy-efficient delivery of conditioned fresh air all year-round.

“With this new applied technology, the HVAC industry aims to be looking forward for a paradigm shift in understanding and addressing IAQ concerns,” Pahwa stresses. “For green buildings, this system assists in scoring substantial LEED points in conjunction with systems like chilled beams.”

GREEN BUILDINGS

Pahwa sees a huge potential in the energy-recovery segment, especially with the increasing moves towards green buildings and growing market for energy-efficient HVAC systems. And here is where DRI sees itself playing a pivotal role in helping clients get a LEED (Leadership in Energy and Environmental Design) certification.

Bear in mind that it is through the application of energy-recovery systems that green sustainable designs become possible, he explains. He also reminds us that HVAC consumes the maximum energy – about 50-60%, followed by lighting loads – in any commercial building, especially in the hot climes of the Middle East. And one of the HVAC areas to look into for energy saving is the ventilation load.

He says that the rotating wheel transfers the sensible and latent energy between the counter flowing exhaust and supply air and, in the process, preconditions – cools, heats, dehumidifies, humidifies – the fresh air. “Thus, by application of high-sensible and moisture recovery wheels, we can bring down the energy consumption of buildings by 10-15%, resulting in more green and sustainable designs,” he stresses.

Having started with the concept of good IAQ, Pahwa says the application of energy recover wheels has been an arduous task. But once everybody – architects, MEP (mechanical, electrical, plumbing) designers, contractors and building owners – saw the potential for reduced costs and energy savings, the application has gradually picked up.

“It has been a long and patient process, but one which has paid dividend in the long run,” he adds. “The world is moving towards sustainable technologies, which not only minimise the negative impact of buildings on the environment but also help in securing carbon credits.”

HEAT EXCHANGERS

In the Middle East, where DRI has its presence for the past 10 years, energy-recovery systems have come a long way and are being applied in almost all new commercial construction projects. Pahwa points out the massive projects in the UAE (especially Dubai and Abu Dhabi), Bahrain, Oman and Saudi Arabia – which are applying air-to-air heat exchangers. The concept is yet to materialise, however, in countries like Egypt, Iran, Lebanon and Jordan in a big way.

If the air-to-air energy recovery systems are not being utilised so much by engineers, despite what experts say that these save energy and lower operating costs, then the challenge lies in the lack of awareness amongst the general public on the benefits of clean indoor air.

This system is built to reduce the load on the air conditioner during summer by lowering the temperature of the fresh outdoor air, and significantly lower heating costs in the winter by transferring heat from the exhaust air to the fresh airstream.

Pahwa says that DRI has been conducting an education campaign on the importance of energy-recovery systems and their role in enhancing IAQ. And the company has received favourable response from the stakeholders, such as architects, project developers, owners and engineers.

“Energy-recovery systems have become increasingly important in light of the current drive to cut down costs, save business money, conserve energy, make buildings green and enhance IAQ,” he says. “Energy conservation is a key priority, and we are offering a system that provides exceptional energy recovery while ventilating buildings.”