Heat Recovery Ventilation Takes Centre Stage in Net-Zero Future

With the UK legally bound to achieve Net Zero by 2050 it is vital we implement changes immediately to ensure we reach this goal. This means the construction industry must review the products it specifies and installs in projects. Louise McHugh, Product Manager at Vent-Axia explains that as a result heat recovery ventilation is gaining traction since it helps reduce carbon emissions, contributing to a Net-Zero future.

Louise McHugh

The UK needs to cut building carbon emissions to meet the 2050 Net-Zero target. Buildings are responsible for 40% of energy consumption and roughly 35% of emissions in Europe. To meet the Government’s 2050 Net-Zero target, buildings need to decarbonise which will involve the wide-scale electrification of heating, a move away from fossil fuels, as well as significant improvements to air tightness and building insulation. Heat recovery ventilation will be a key technology to help deliver another means of carbon avoidance by preventing heat loss, so as a technology it is set for significant growth.

To achieve carbon reductions, buildings are being designed to be more thermally efficient through insulation and increased air tightness to prevent heat loss. However, if ventilation is not considered too, it can result in condensation, mould, and poor indoor air quality (IAQ). Therefore, energy-efficient heat recovery ventilation systems offer a solution that delivers clean, filtered air while also recovering the heat that would otherwise be wasted.

High Efficiency

Manufacturers therefore designed the latest commercial heat recovery ventilation, such as Vent-Axia’s Sentinel Apex, to be highly energy efficient with industry-leading low specific fan powers (SFP) and low embodied carbon. However, manufacturers have also made occupant comfort a priority by ensuring units operate quietly and effectively improve IAQ. Recovering up to 93% heat recovery efficiency these types of unit save huge amounts of energy that would be otherwise wasted.

While specifying a heat recovery unit that features low energy usage and high thermal efficiency is crucial for lowering carbon emissions, it is equally important to consider the unit’s performance once installed. To ensure a building operates as designed it is vital to ensure it is commissioned accurately. To make commissioning simple the latest heat recovery units therefore feature advanced control systems providing on board, in-room and App-based control, where full functionality commissioning and monitoring is provided as standard, ensuring a unit meets its energy efficiency targets as designed.

Avoiding waste

To avoid energy wastage, it is also crucial to select a heat recovery unit where every element has been considered. Heat recovery featuring demand control optimises IAQ while minimising ventilation energy consumption, only ventilating when required. Demand ventilation also helps with compliance with Approved Document F of the Building Regulations which states occupied rooms in commercial buildings must have means of monitoring IAQ. CO₂ demand-controlled ventilation can ensure good IAQ as per Part F.

Although, when selecting a heat recovery unit there are some elements that can hamper efficiency. To maximise good IAQ high-level filtration is vital. But, filters need to be chosen wisely, since a poor choice might affect the heat recovery unit’s efficiency, resulting in a higher SFP.

Summer bypass is another feature to consider when specifying heat recovery ventilation. As buildings become increasingly airtight the threat of buildings overheating is growing. However, a summer bypass is another element that can negatively affect performance. When choosing a commercial heat recovery unit consider an integral automatic summer bypass designed to provide free cooling when available but ensure it is sized to eliminate performance loss.

Meanwhile, over specification wastes energy so sizing in general is important. By choosing a heat recovery unit that comes in multiple sizes it is easier to select a unit which meets airflow requirements. There are free cloud-based tools available that allow users to select fans to exact duty points so the fan will operate in a building as designed.

Embodied Carbon

Embodied energy has now come to the fore as energy efficiency reaches its pinnacle. To reduce embodied energy it is important to select products that are UK-manufactured with a short supply chain. Also opting for a product that is serviceable and maintainable so each component can be removed and replaced, if necessary, is helpful as it extends the heat recovery unit’s life. For instance, the Apex is completely serviceable and maintainable with complete access to all internal components so new motors or heating cells can replace old ones, increasing the unit’s longevity. Its design allows it to be repurposed or disassembled and recycled at the end of its life, which all adds up to creating less waste, further enhancing its life-cycle credentials

When designing a low carbon or carbon-neutral building, obtaining accurate and up-to-date embodied carbon information is crucial. However, embodied energy is a complex topic, one of the challenges is around transparency and data sharing throughout the material and building lifecycle, along the supply chain.

Manufacturers are therefore now taking additional steps to provide the embodied carbon information by using CIBSE TM65 data collection methodology to collect accurate and detailed embodied carbon information. Working from a component level, this methodology ensures data is comprehensive, and up-to-date. For example, Vent-Axia can provide TM65 data for its Sentinel Apex commercial heat recovery system to help customers understand the wider life cycle assessment. TM65 considers embodied carbon to be the greenhouse gas emissions associated with the manufacture of a product, its installation, maintenance, repair, replacement and end of life.

When it comes to selecting how to ventilate a low carbon or carbon neutral building, heat recovery ventilation therefore comes to the fore as a good solution. By prioritising energy efficiency, minimising energy wastage and carefully measuring embodied energy when selecting a heat recovery unit, we can successfully reduce carbon in buildings as we head towards UK Net-Zero 2050 targets.

ABOUT VENT-AXIA

Boasting over 85 years’ experience, Vent-Axia is the ventilation sector’s clear leader, chief innovator and forerunner in developing energy efficient products that help provide good indoor air quality. Committed to improving indoor air quality and comfort in both homes and buildings, Vent-Axia provides the sector’s most comprehensive choice from any single manufacturer. Vent-Axia’s range covers not just air movement and ventilation technologies but heat recovery, electric heating, hand dryers, cooling and clean-air systems for residential, commercial, public sector and industrial applications.