Innovative HVAC solutions paving the way to net-zero emissions

Matteo Galenda, Application Specialist for HVAC Residential at CAREL, emphasises the HVAC industry’s commitment to sustainability through innovative technologies like IoT, AI, and variable-speed compressors. He highlights the integration of renewable energy, low-GWP refrigerants, and innovations that will drive the industry toward achieving net-zero emission goals in residential and commercial spaces.

What factors or technology improvements influence HVAC energy efficiency to reduce greenhouse gas emissions?

A drastic reduction of greenhouse gas emissions can be undoubtedly achieved by using heat pumps, which are very efficient heating systems, in the residential sector. Smart control systems, such as smart thermostats and IoT sensors, can be installed indoors. Having an adequate heat distribution system and appropriate building insulation is fundamental. It is possible to be completely free from fossil fuels to support sustainability by integrating energy production from renewable sources. Finally, ventilation systems with heat recovery can help to minimise energy consumption. Regulations, with respective guidelines and bans, and government incentives are decisive factors for promoting the adoption of high-efficiency technologies.

How can variable-speed compressors contribute to reducing the energy footprint of HVAC systems?

Variable-speed compressors are indispensable in applications where source temperatures vary significantly, such as in air/water heat pumps. Compared to an on/off compressor, they have a high efficiency at partial loads. The load determines power consumption from the grid because this is related to the rotational speed of the motors and will vary accordingly. An inverter system is needed for the power supply. Also, an electronic expansion valve (EEV) should be installed in the refrigeration circuit.  With this solution, the continuous on/off cycles, which are decremental to the compressor, are avoided, and its service life is extended. In addition, precise speed control helps maintain a stable temperature for improved indoor comfort. Laboratory tests have shown that the combination of variable speed compressors and EEVs significantly increases efficiency, reducing carbon footprint and operating costs.

Why is the shift towards low-GWP refrigerants important in the HVACR industry?

Switching to low-GWP refrigerants significantly reduces the environmental impact compared to HFC, CFC and HCFC refrigerants. HFOs and natural refrigerants, such as hydrocarbons like propane, CO2, ammonia, etc., have a negligible impact on global warming if they get released into the atmosphere. Their thermodynamic properties can improve the energy efficiency of HVACR systems. Propane is the Main candidate for use in heat pumps in Europe. Its performance is excellent. It allows condensation at higher temperatures than R-32, with lower compressor discharge temperatures. In short, it reduces direct emissions and meets increasingly stringent regulations while reducing energy consumption.

What role do IoT and AI technologies have for HVAC systems for decarbonisation efforts?

In systems, IoT sensors continuously monitor electrical and thermodynamic performance and parameters such as temperature, humidity, and air quality through real-time data collection. The data are analysed by implementing AI and machine learning algorithms to maximise system efficiency based on actual demand, reducing energy waste. Grids and load systems are becoming more intelligent and interconnected (smart grids), enabling better energy consumption management. The expected increase in renewable energy availability will lead to regulating HVAC unit consumption, avoiding demand peaks and limiting the use of fossil fuels. IoT and AI facilitate predictive maintenance, anticipating and reporting faults, avoiding system downtime, discomfort and operational inefficiencies. Maintenance costs will be reduced, and system life will be extended.

In what ways do energy-efficient HVAC systems improve indoor environments in residential and commercial settings?

First, high-efficiency HVAC systems provide the best indoor comfort and control humidity and air quality. In particular, air quality, if reduced, leads to the spread of bacteria, dust and allergens, causing illnesses and allergies. The Covid 19 outbreak highlighted how a healthy environment equipped with a proper ventilation system with a uniform air exchange and a filtration system is essential to reducing the spread of disease. It also positively impacts the environment by lowering system emissions and energy consumption. Integration with renewable energy sources, heat pump systems, thermostats and smart sensors also increases the economic value of the property.

What strategies will you suggest for maximising HVAC efficiency in sustainable building management?

Several strategies can be implemented to achieve maximum efficiency. Further, using heat pumps with variable-speed compressors and electronic expansion valves is the first step to increasing energy efficiency. Intelligent thermostats, sensors and real-time energy management systems complete the picture. Other key factors include integrating renewable energy sources, such as solar or geothermal, and improving building insulation with heat recovery systems. Finally, proper maintenance, regular cleaning of the installations and the individual user’s adoption of consumption behaviours aimed at reducing consumption are essential.

What are your recommendations for achieving a target of net zero emissions?

This goal is challenging, but we are going in the right direction. We need to act in several areas in an integrated manner. Energy production must be from renewable sources to decarbonise production. Energy efficiency must be improved across all sectors, including transportation, buildings, and industry, utilising advanced technologies and sustainable design principles. Electric car fleets must be expanded. And the energy distribution infrastructure must be improved, including lines and charging stations. Other practices, such as reforestation and a circular economy using environmentally sustainable and recycled materials, will contribute to removing atmospheric carbon.