Heat Recovery Ventilators (HRV) - Expert Commentary

Reducing Your HVAC Carbon Footprint: How The Sector Can Become More Sustainable In The Journey To Net Zero
Reducing Your HVAC Carbon Footprint: How The Sector Can Become More Sustainable In The Journey To Net Zero

With ongoing efforts from governments across the globe to reduce carbon emissions and with an ever greater focus on sustainability, it is vital that the HVAC sector does its part in becoming more environmentally conscious. And, while there have been steps to become more sustainable, there is a huge amount that still needs to be done to make sure that many of the targets that have been set are attainable. In buildings, both large and small, industrial heating accounts for roughly two thirds of industrial energy demand and around a fifth of global energy consumption. Figures like this show the need to have efficient and environmentally-friendly HVAC equipment in place to make the crucial steps towards reducing the contributions these systems make to our carbon footprint. High energy consumption in construction sector A 2019 report by The International Environment Agency (IEA) showed that the buildings and construction sectors combined were responsible for over 30% of global energy consumption and nearly 40% of carbon emissions. This is indicative of the steps the sector needs to take to play its role in a more eco-friendly society, some of which are already underway. However, much more needs to be done if the UK is to reach its goal of reaching net zero carbon emissions by 2050. As we envisage what a post-COVID world might look like, businesses and governments are continuing to put sustainability and lower carbon emissions at the forefront of their planning and the HVAC sector is certainly no exception. But with change in the sector a daunting prospect, decision-makers often don’t know where to start. Smart Technology use in HVAC systems Smart HVAC uses sensors that integrate with a building’s automation system With the constant growth and greater deployment of smart technologies within the HVAC sector, this is certainly a way that systems can become more efficient. Smart HVAC uses sensors that integrate with a building’s automation system. These sensors then collect information about conditions throughout the building. Heat waves are now a far more common occurrence in the United Kingdom. The Met Office estimates they are up to 30 times more likely and will be a bi-annual occurrence by 2050. It is important that any uptake in HVAC usage doesn’t lead to a drastic increase in emission generation. This is one of the areas where smart systems will become crucial. Many scientists have been unequivocal in their sentiment that heat waves are a cause of greater emissions and expect temperature records in the UK and Europe to be broken more regularly, so sites will need to be equipped to handle these conditions. Regulating temperature with hand-held devices With wireless systems now much more commonplace, temperatures can be controlled easily from hand-held devices. With these new technologies, those managing the systems can also benefit from remote monitoring and maintenance, reducing the need to travel to the site for yet another environmental incentive. To accompany the smart systems, equipment including smart thermostats can be installed to maximize HVAC efficiency. Other smart systems available to businesses include smart furnaces and air conditioning units that are far easier to operate than their traditional counterparts. Reducing unnecessary ventilation While global temperatures continue to rise, air conditioning usage has increased and has contributed to greater levels of energy usage. A huge amount of needless emissions are generated by unnecessary ventilation, contributing heavily to heat loss and overall energy wastage. Recirculation of air is a traditionally lower energy cost method of retaining heat and keeping emissions low, however, we must be mindful of the risks associated with recirculating air. The risk of circulating diseases is negated somewhat with heat recovery ventilation, which both removes the risk of disease spreading and improves energy consumption. Efficiency performance of new AC units Air conditioning units in particular contribute significantly to a building’s energy consumption Air conditioning units in particular contribute significantly to a building’s energy consumption, equating to 10% of the UK’s electricity consumption and as such it is important that we bear in mind ways to counteract the emissions this creates. Global energy demand for air conditioning units is expected to triple by 2050, as temperatures continue to rise year on year. The efficiency performance of new air conditioning units will be the key, when it comes to ensuring that escalating demand does not equate to greater emissions. Another issue for suppliers and manufacturers to address is differing rates of consumption for AC units in different countries, with units sold in Japan and the EU typically more efficient than those found in China and the US. Modularization Modular HVACs have also become increasingly popular in recent years. Modular HVACs are responsible for heating, cooling and distributing air through an entire building, with their increase in popularity largely down to their greater levels of energy efficiency, cost effectiveness, flexibility and substantial ease of installation and maintenance. Modular HVACs can be tailored specifically for workspaces and they often allow work to be done on the systems without disturbing the workforce, achieved primarily through rooftop placement. Commercial workspaces are larger and often require differing needs to residential properties and can cater to a wide range of the specific requirements of work and commercial spaces. As we strive for lower carbon emissions, it seems that this trend will continue and will become a key area in reducing emissions that HVACs have traditionally generated. System maintenance and training To meet government and industry requirements, many new buildings will require HVAC systems that can be maintained simply in order to perform in a more energy efficient way. Many companies are looking at ways to become climate neutral and significantly reduce their footprint Many companies are looking at ways to become climate neutral and significantly reduce their footprint. Companies are following the likes of German-based company, Wilo Group, who have announced they are committing to sustainable manufacturing by developing a new carbon neutral plant and HQ in the next few years. Lowering carbon footprint As we continue to move towards an ever more environmentally conscious society, it will be of paramount importance for companies, governments and the public to think about ways in which we can lower carbon emissions. Smart technologies will certainly be at the forefront of this, negating many needless journeys and making it easier for industries to adjust settings and tackle issues remotely. Greater levels of training will help equip us with the tools to make sure we are best placed to reduce emissions and be more sustainable as a result. While the steps outlined above do show some progress and measures we can take, there is far more that we can do as a sector to significantly reduce HVAC’s carbon footprint and once we have moved beyond the impact of the COVID-19 pandemic, this will surely be at the front of industry leader minds.

How HVAC Solutions Could Help Lead The Way Out Of The Pandemic
How HVAC Solutions Could Help Lead The Way Out Of The Pandemic

With the roadmap laid out for the government to guide us out of lockdown, the end of the pandemic seems as though it could be in sight. However, HVAC units remain outdated in hotels, hospitals, schools, and offices and there is a worry that COVID-19 can still spread quickly and easily through air vents, mitigating the effects of lockdowns and vaccinations. Dr. Rhys Thomas, Chief Scientific Officer at infection mitigation specialist PP-L and a frontline NHS doctor, says that the government’s neglect of using HVAC solutions to reduce transmission is a major oversight. Airborne transmission indoors By failing to follow the lead of other nations that are now recognizing the importance of ventilation in relation to the airborne nature of the virus, the UK’s approach hasn’t been as comprehensive or as forceful as it could be, with quietly introduced, piecemeal changes to regulations being too little, too late. At the moment, some governments don’t want to come out and admit that COVID-19 is an airborne hazard and that their failure to recognize it as such has led to higher infection and mortality rates and suffered even greater impacts from new variants. Research shows that 80% of the spread of the virus is through airborne transmission indoors– the inhalation of infected droplets that are moving around in the room’s air currents or ventilation systems– which a two-meter distance or the opening of the window is unlikely to combat. New quarantine hotels The UK was geared up for an influenza-like pandemic rather than an airborne one The airborne nature of COVID-19 is what has caught governments off guard and meant we are still playing catch-up while new variants are starting to appear, which was also always to be expected. In terms of preparedness, the UK was geared up for an influenza-like pandemic rather than an airborne one, such as the challenge posed by a SARS coronavirus. As with all airborne illnesses, the greatest risk of transmission is indoors and in confined spaces such as public transport, office buildings, factories, and even potentially the new quarantine hotels which are being introduced to prevent the spread of the virus. The governments ‘hands, face, space’ messaging cover the opening of windows to help with airflow, but the reality is much more complex. Latest SARS Coronavirus The risk of infection indoors is vastly higher than outside, and current advice simply isn’t enough. There’s a perception – even in hospitals – that fresh air is clean air. I’ve been shocked to see hospitals that I’ve visited assuming that simply opening a window is enough. That is simply not the case – the air needs to be disinfected by ultraviolet light for it to be clean enough to prevent the spread of coronaviruses. I saw this in practice in the first SARS pandemic in 2003, where UV was used and proved incredibly effective in South East Asian hospitals once again against the latest SARS Coronavirus that causes COVID-19. The spread of the virus around the Diamond Princess cruise ship, which hit global headlines in January 2020 when more than 700 passengers and crew tested positive for COVID-19, has become a case-in-point for the theory behind the airborne transmission. Killing airborne contaminants Part F of the Building Regulations on ventilation has been updated and is out to consultation Researchers from Harvard and the Illinois Institute of Technology developed a computer model of the cruise ship outbreak, which found that the virus spread most readily in microscopic droplets light enough to linger in the air. The research added to the pressure already being placed on the World Health Organization to recognize the airborne dangers of the virus, including an open letter signed by more than 200 experts. The key point here is that there has been some level of recognition from various government departments that the virus is airborne, and they have mitigated accordingly. Part F of the Building Regulations on ventilation has been updated and is out to consultation, and the Health and Safety Executive’s COVID-Secure Guidance for the Workplace on Ventilation has also been quietly updated in recent weeks to recommend the use of ultraviolet air filtration systems, which are proven to kill airborne contaminants. Key communication issue These UK regulations are now, at last, starting to get more aligned to other global institutions’ recommendations such at the renowned Centers for Disease Control and Prevention (CDC) who support the importance of ventilation and UV devices to significantly reduce infection risk. This is a positive step, but the key communication issue is that if the government don’t fully endorse and be more vocal about the airborne threat of COVID-19, and regulatory changes being made, then neither will the wider public. This is a huge issue because the government is already preparing for this virus to be around in some form for many years to come. With 40 million doses of vaccine set to arrive in 2022 and an overall supply line that is set to last until 2025, it’s clear that there is an acknowledgment that this will be a long fight. The SAGE scientists like Professor Chris Whitty and Sir Patrick Vallance are also referring to this virus as endemic now. Long-Term readiness The government is already building long-term readiness and diluting the risks by using different suppliers With 407 million doses of vaccine on order, the government is already building long-term readiness and diluting the risks by using different suppliers, but without the acknowledgment of the airborne risks, this can only do so much – it needs to be a joined-up, blended approach. Prevention is better than the alternative because in this case, there is unlikely to be a cure for a virus that spreads and mutates at the rate this one does. Trying to keep ahead of this virus is a dangerous game. It is incredibly adaptable and there is an awful lot of guesswork about predicting the spread and virulence of new and more easily spread strains. Ongoing lockdowns are simply not an option and are increasingly ineffective as people struggle with the monotony and isolation they bring. We need to get on the front foot and not only rely purely on medicine to help solve this crisis. Air filtration systems Engineered solutions like UV-C (also known as UVGI) and air filtration systems are needed wherever possible to help cut this virus at the knees and stop transmission in the first instance. These solutions are now being brought in by several industries and many countries around the world are specifically recommending them because they are recognizing that the guidelines in their current form aren’t doing enough. Those industries such as food manufacturing and production that rely on having people on the ground and in their factories are having to look beyond what they are advised and finding solutions that actually do work. Hospitals, schools, and hotels are the next places that need to be looking at this kind of response, especially with the government’s travel regulations meaning that potentially infected travelers are being kept in potentially inadequately ventilated spaces that could actually accelerate contagion spread to other travelers or staff. Action needs to be taken now, or we risk the further unnecessary spread of this dangerous pathogen.

Using Silicone To Improve HVAC Insulation & Energy Efficiency
Using Silicone To Improve HVAC Insulation & Energy Efficiency

The modern technological world is filled with ‘extrusions’. They are all around us, in the form of small and not-so-small cross sections. The function of an extrusion is to form seals between components of complex machinery and keep them functional. And, depending on the ‘type’ used, they can make a big difference to how a machine operates. Some of the most desirable types of extrusion — and especially for use in HVAC systems — are those made from silicone. Silicone, which is a type of rubber, has a robust set of properties. For one, silicone can withstand extreme temperatures, both high and low. Semi-Exterior environments Ranging from -60°C to temperatures exceeding 200°C. (And there are even higher grades that can be manufactured to withstand temperatures well above 200°C.) Ideal for HVAC units that work round the clock to keep large numbers of people in large buildings comfortable in summer and winter conditions. In addition to this, silicone is also one of the more resistant properties to the constant vibrations of working machinery. It can be difficult to locate the source of the problem if a tiny extrusion has dislodged. Vibration-resistant properties make silicone extrusions less likely to disengage or fall out of place, therefore minimizing the need for costly repairs. Finally, silicone is also more durable than most other materials when it comes to exterior or semi-exterior environments, such as that of rain or ultraviolet light. Protecting electrical components Silicone is useful in HVAC systems because it offers enhanced sealing and compression protections As a result of this favorability, there is already a considerable number of different types of silicone extrusions that can be found in a lot of HVAC systems. These include HVAC sealing gaskets, hatch seals and vibration isolation pads. But also silicone sponges, which act as a protective layer of thermal insulation. As well as providing thermal insulation, silicone sponges can double-up as a form of acoustic insulation, with considerable noise reduction and anti-squeal properties. Silicone enclosure gaskets protect electrical components, and environmental seals — as the name suggests — help to keep everything protected from the sometimes harsh elements of the environment outside. Silicone is useful in HVAC systems because it offers enhanced sealing and compression protections over most other materials. Closed cell structure On a material level, silicone has a ‘closed cell structure’, which helps to keep out moisture ingress, along with water and dust. The combination of a closed cell structure, along with sealing and compression benefits, makes silicone ideal for exterior seals and gaskets in and around HVAC systems. The softer grades of Silicone have an excellent memory and low stress relaxation, which in turn helps to prevent common faults with HVAC systems — usually caused by gasket failures made from other materials that soften and compress inaccurately. The low stress relaxation properties require minimal force on behalf of the engineers sealing the enclosures, while the memory-properties of the silicone allow it to conform to awkward shapes and gaps of various widths. Manufacturing HVAC systems proactively with silicone in mind can allow more design flexibility on behalf of the engineers. Inevitable rapid movements General purpose solid silicone or silicone sponge is suitable for many HVAC applications And, as mentioned above, vibration isolation pads work as dampers to protect against the inevitable rapid movements of the systems as they power along. But also to help withstand the vibrations of HVAC units on transport systems, such as buses and trains, which naturally vibrate as they run over imperfections on rail and road tracks. As it happens, general purpose solid silicone or silicone sponge is suitable for many HVAC applications, not just those discussed above. The designs of the extrusions would be different, reflective of their function, but the material would be the same. In some instances, customers may also require a flame retardant silicone — certified to UL94 specifications — in order to meet safety standards in certain situations or environments. Great temperature ranges For all its material advantages, silicone is generally more expensive than the other types of material rubber that are used to manufacture extrusions, such as ethylene propylene diene monomer (EPDM). And while other materials do of course have stand-out benefits of their own — EPDM for example is more hard-wearing than silicone — silicone is still often the extrusion ‘type’ of choice because of its ability to withstand great temperature ranges. This is very important for heating and air conditioning systems. Because some of the most common factors that cause HVAC systems to break down are as a result of seal and gasket failure, which can come about as a result of an overheating unit. Very cold environment Chances of a unit overheating can be just as likely — in fact perhaps more so — where the system has to operate in a very cold environment. With the threat of climate change etched more than ever into the public discussion, we can predict that there will be a steady increase in the amount that this material is used to make up the HVAC seals. And not just because, as temperatures continue to increase and summers get hotter and more prolonged, there will be an increased demand for them. Effective public relations It is no secret that HVAC systems can be relatively expensive to run It will become a matter of effective public relations for managers, building regulators and transport officers to make sure that the equipment they are using — and making — is ‘green’. By using the right materials that help conserve energy and increase efficiency, this will not only sit right with the general public, it should also be more economical, too. It is no secret that HVAC systems can be relatively expensive to run. Minimizing wastage, and the time spent on call outs and repairs will make a notable difference. Of course there are many other ways to also set about making air conditioning and heating units more efficient. Using seals or gaskets made from silicone is just one small piece of the puzzle. But utilizing them will almost certainly be more beneficial than you might imagine. And anything that is a step in the right direction is a welcome change.

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