Clean air: creating more efficient HVAC systems

The air conditioning system is one of the most demanding items on a passenger ship when it comes to electrical load-balancing. With a significant energy cost, operators demand that HVAC systems run as efficiently as possible while providing a comfortable environment for passengers. Teknotherm’s project manager Sigbjorn Tyssen explains that digital technologies such as data analytics could play a significant role in making HVAC systems more efficient.

“The traditional HVAC skills such as fan curves, noise calculations and knowledge about refrigeration cycles will not go out of style,” Tyssen says, but he adds that automation is becoming ever more important. “Knowledge of systems such as AI, machine learning and neural networks is something we need to learn more about. The technology is there, and the data must be collected.”

“The future HVAC system will react faster, but also move energy to where it is needed, plan when it is needed and produce it in the most energy-efficient way,” he says. Recent and forthcoming deliveries illustrate the role HVAC systems can play in boosting energy efficiency on passenger ships.

A heat recovery wheel is being incorporated into the ventilation systems to aid energy saving. Comprising a circular honeycomb matrix made of heat-absorbing material, the heat recovery wheel rotates within the supply and exhaust air streams of air-handling systems.

As it rotates, heat is gathered from the exhaust air stream in half of the rotation and given to the fresh air stream on the other half of the rotation, transferring waste heat energy from the exhaust air stream to the fresh air stream via the matrix material.

HVAC systems are known for drawing a lot of power, so maximising efficiency is essential to maximising fuel efficiency and lowering costs.

Big data and digitalisation are becoming ever more important in this process, and HVAC specialist Koja Marine is pioneering its application. By gathering data from the HVAC plant on board, its energy efficiency can be fine-tuned using analytical tools, explains managing director Esko Nousiainen. In new build applications, energy savings up of to 30 percent can be achieved in cabin areas using such methods, he adds.

The company is also researching applications of internet-of-things (IoT) technology. This includes using low-resolution, heat-seeking sensors to monitor passenger flow and adjust AC ventilation in a given area accordingly.