IAQ IQ: Indoor Air Quality and You

About IAQ IQ: Indoor Air Quality and You

When was the last time you thought about the quality of the air you breathe in your home or office? If it's been a while, we're here to change that. This is Indoor Air Quality IQ, a podcast from RenewAire - where our goal is to raise your IQ about IAQ.

Publisher

RenewAire

Category

business

Language

en

Explicit

No

First episode

18 Dec 2020

Latest episode

15 Dec 2023

Latest episodes

20 episodes in the feed.

1. 

   15 Dec 2023

   Decarbonization and Enhanced Ventilation: ERV + DOAS, Part 2

   The latest episode of “IAQ IQ: Indoor Air Quality & You” examined how enhanced ventilation via energy recovery ventilators (ERVs) and dedicated outdoor air systems (DOAS) can support decarbonization. Conducted in conjunction with New York State Energy Research and Development Authority (NYSERDA), the podcast showcased three participants. Host Michelle Dawn Mooney spoke with Michael Reed, Head of Large Buildings, Advanced Energy Solutions, NYSERDA; Alex Smith, Mid-Atlantic Regional Sales Director, RenewAire and Nick Agopian. Below are the key points raised during the podcast and a summary of the discussion. Before we jump into the content of the podcast, let’s take a quick look at NYSERDA. Since its founding in 1975, NYSERDA has worked to promote energy efficiency, renewable energy and emissions reduction across New York’s economy and energy system. In addition to supporting clean energy and technologies, the organization is working to advance equity and inclusivity, jobs and economic development, public health and community resilience. Kicking off the podcast was Reed who explained decarbonization. “It means reducing and eventually eliminating greenhouse-gas (GHG) emissions. When it comes to buildings, decarbonization means phasing out a reliance on fossil fuels typically for heating and hot water." How is decarbonization made possible in the built environment? Reed continued, “This is accomplished through reducing overall needs for energy via measures such as envelope improvements and advanced controls, recovering and reusing heat that would otherwise be wasted and replacing carbon intensive equipment like fossil-fuel combustion with heat-pump systems.” Building engineers can play a key role in supporting decarbonization said Smith, but first he explained the severity of the issue. “The built environment is responsible for almost 50% of carbon (CO2) emissions into the atmosphere. Within the built environment, over half of the total is the operation of the building. This process incorporates the HVAC, which is the biggest energy hog in a building’s operation.” Smith continued with some strategies building engineers can apply to address decarbonization. “There are a number of initiatives that can be taken, such as LED lighting and architectural features to help with solar load. But the main thing that should be the point of focus is the HVAC system.” What specifically can engineers do with the HVAC system to support decarbonization? Smith explained the options. “There are a number of HVAC strategies. We’re seeing more heat pumps being used, whether air to air or water to air. Also energy recovery, which is particularly important when it comes to buildings with existing equipment not designed to allow for the increased ventilation we need for occupant health and better IAQ.” Smith went on and explained that handling humidity is a key challenge of conventional systems. “Such equipment is not designed to dehumidify outdoor air, so what you can do is introduce energy recovery to mitigate the outdoor air load on existing equipment. This allows it to operate more efficiently and with less parasitic energy. Energy recovery is particularly important especially when it comes to retrofits of existing buildings.” To achieve high-level IAQ, as much outdoor air as possible needs to be brought indoors. However, conventional systems can’t handle this load. Therefore, the outdoor air must be handled by another system. Smith explained this concept in more detail. “We’ve discussed that standard AC equipment is not designed to dehumidify a high percentage (or 100%) outdoor air. If you add an energy recovery unit to the front end of existing equipment, that’s a big help because the energy recovery component can partially cool and partially dehumidify that outdoor air and then send it to the existing ac equipment. This eases the load and allows it to operate more efficiently.” “But even in those circumstances, the amount of outdoor air you can bring in is still limited. The problem is if you have high percentage or 100% outdoor air, that strategy will not work. In that case, we must use a dedicated outdoor air system (DOAS). A DOAS is distinct from existing equipment because it’s designed specifically for dehumidifying 100% outdoor air. It comes down to two things: A DOAS must provide the minimum ventilation requirement and be capable of dehumidifying the entire latent load, which is from both the outdoor air and people in the space.” Thus, what exactly is decoupling? Smith continued to explain this concept. “A DOAS is designed to work in conjunction with the existing AC unit that’s servicing the space. What we’re doing is separating—or decoupling—the latent load from the AC unit and putting it onto the DOAS. The result is the zone unit or AC system that’s serving the space only has to cool the sensible load.” Consequently, energy efficiency in the HVAC process is optimized. Wrapping up the podcast was Reed who reviewed the new NYSERDA program, Enhanced Ventilation: ERV +DOAS. “The goal of the program is to shine a giant spotlight on this heat recovery opportunity that exists in New York City and New York State. We want to get the private sector to seize on this opportunity, create repeatable solutions and deploy those solutions across the built environment.” One of the main barriers to adoption for energy-efficient systems is cost, and that’s where this NYSERDA program comes in. “That type of work requires an upfront investment and we’re trying to use public ratepayer dollars to get the industry started on this opportunity area,” said Reed. “We hope to create resources to help others in this industry follow the leaders and drive an increase in market share to manufacturers and other solution providers who are able to solve this problem.”

2. 

   15 Dec 2023

   Decarbonization and Enhanced Ventilation: ERV + DOAS, Part 1

   The latest episode of “IAQ IQ: Indoor Air Quality & You” examined how enhanced ventilation via energy recovery ventilators (ERVs) and dedicated outdoor air systems (DOAS) can support decarbonization. Conducted in conjunction with New York State Energy Research and Development Authority (NYSERDA), the podcast showcased three participants. Host Michelle Dawn Mooney spoke with Michael Reed, Head of Large Buildings, Advanced Energy Solutions, NYSERDA; Alex Smith, Mid-Atlantic Regional Sales Director, RenewAire and Nick Agopian. Below are the key points raised during the podcast and a summary of the discussion. Before we jump into the content of the podcast, let’s take a quick look at NYSERDA. Since its founding in 1975, NYSERDA has worked to promote energy efficiency, renewable energy and emissions reduction across New York’s economy and energy system. In addition to supporting clean energy and technologies, the organization is working to advance equity and inclusivity, jobs and economic development, public health and community resilience. Kicking off the podcast was Reed who explained decarbonization. “It means reducing and eventually eliminating greenhouse-gas (GHG) emissions. When it comes to buildings, decarbonization means phasing out a reliance on fossil fuels typically for heating and hot water." How is decarbonization made possible in the built environment? Reed continued, “This is accomplished through reducing overall needs for energy via measures such as envelope improvements and advanced controls, recovering and reusing heat that would otherwise be wasted and replacing carbon intensive equipment like fossil-fuel combustion with heat-pump systems.” Building engineers can play a key role in supporting decarbonization said Smith, but first he explained the severity of the issue. “The built environment is responsible for almost 50% of carbon (CO2) emissions into the atmosphere. Within the built environment, over half of the total is the operation of the building. This process incorporates the HVAC, which is the biggest energy hog in a building’s operation.” Smith continued with some strategies building engineers can apply to address decarbonization. “There are a number of initiatives that can be taken, such as LED lighting and architectural features to help with solar load. But the main thing that should be the point of focus is the HVAC system.” What specifically can engineers do with the HVAC system to support decarbonization? Smith explained the options. “There are a number of HVAC strategies. We’re seeing more heat pumps being used, whether air to air or water to air. Also energy recovery, which is particularly important when it comes to buildings with existing equipment not designed to allow for the increased ventilation we need for occupant health and better IAQ.” Smith went on and explained that handling humidity is a key challenge of conventional systems. “Such equipment is not designed to dehumidify outdoor air, so what you can do is introduce energy recovery to mitigate the outdoor air load on existing equipment. This allows it to operate more efficiently and with less parasitic energy. Energy recovery is particularly important especially when it comes to retrofits of existing buildings.” To achieve high-level IAQ, as much outdoor air as possible needs to be brought indoors. However, conventional systems can’t handle this load. Therefore, the outdoor air must be handled by another system. Smith explained this concept in more detail. “We’ve discussed that standard AC equipment is not designed to dehumidify a high percentage (or 100%) outdoor air. If you add an energy recovery unit to the front end of existing equipment, that’s a big help because the energy recovery component can partially cool and partially dehumidify that outdoor air and then send it to the existing ac equipment. This eases the load and allows it to operate more efficiently.” “But even in those circumstances, the amount of outdoor air you can bring in is still limited. The problem is if you have high percentage or 100% outdoor air, that strategy will not work. In that case, we must use a dedicated outdoor air system (DOAS). A DOAS is distinct from existing equipment because it’s designed specifically for dehumidifying 100% outdoor air. It comes down to two things: A DOAS must provide the minimum ventilation requirement and be capable of dehumidifying the entire latent load, which is from both the outdoor air and people in the space.” Thus, what exactly is decoupling? Smith continued to explain this concept. “A DOAS is designed to work in conjunction with the existing AC unit that’s servicing the space. What we’re doing is separating—or decoupling—the latent load from the AC unit and putting it onto the DOAS. The result is the zone unit or AC system that’s serving the space only has to cool the sensible load.” Consequently, energy efficiency in the HVAC process is optimized. Wrapping up the podcast was Reed who reviewed the new NYSERDA program, Enhanced Ventilation: ERV +DOAS. “The goal of the program is to shine a giant spotlight on this heat recovery opportunity that exists in New York City and New York State. We want to get the private sector to seize on this opportunity, create repeatable solutions and deploy those solutions across the built environment.” One of the main barriers to adoption for energy-efficient systems is cost, and that’s where this NYSERDA program comes in. “That type of work requires an upfront investment and we’re trying to use public ratepayer dollars to get the industry started on this opportunity area,” said Reed. “We hope to create resources to help others in this industry follow the leaders and drive an increase in market share to manufacturers and other solution providers who are able to solve this problem.”

3. 

   24 Jul 2023

   Maximize Ventilation Potential with ERVs as Compared to HRVs

   What Are the Key Differences Between ERVs and HRVs? As the names above explain, ERVs are ventilators that recover energy while HRVs recover heat. But how exactly are they different? The first key variance is that HRVs only recover heat whereas ERVs recover both heat and humidity. This is explained later on in the podcast. Additional differences between ERVs and HRVs include the following: • HRVs are prone to condensation and require drain pans. ERVs don’t experience this and don’t need drain pans. • HRVs cannot be installed in any orientation because of their drain pans. ERVs can be installed in multiple orientations. • HRVs must go through an active defrost, which limits ventilation potential. ERVs don’t need defrost, which maximizes energy efficiency and ventilation potential. • HRVs can only be installed in colder northern climates. ERVs can be installed in any climate. Before continuing on, let’s take a more detailed look at sensible vs. latent energy and why they both matter for ventilation. Sensible energy is dry heat and is the temperature that you can feel or sense. Latent energy is wet heat and is the energy a substance absorbs or releases when a phase change occurs, such as water converting into vapor. Unlike sensible energy, latent energy doesn’t change the temperature and thus can’t be felt. When looking at the combination of both sensible and latent energy, this is called total energy. ERVs recover total energy (heat and humidity), whereas HRVs only recover sensible energy (heat). As Marks outlined in the podcast, “the main difference between the two is an HRV only recovers sensible heat in the air exchange between the exhaust air and incoming air and an ERV recovers both total energy consisting of heat and humidity.” He continued with an example: “In the case where you have a controlled space with a desired humidity level, you’re sending out humidity with the exhaust air if the outdoor air coming inside is too humid. This is the primary advantage of having an ERV over an HRV. An HRV will just warm up one airstream and cool down the other airstream.” Why are both sensible and latent energy important for ventilation? Agopian dug a little deeper on the topic. “If I tell you it’s 95 degrees outdoors, you’ll say it’s hot, but if I say it’s minus 20, then you’ll say it’s pretty cold. That’s the actual temperature that your body senses, and this is sensible energy. The wet heat that is in concert with this dry heat is the humidity." Agopian continued, "when delineating the difference between sensible energy (the dry heat or actual temperature) and the latent energy (the moisture that’s in the air) we realize that there are two parts to the equation to give you your total energy. Only focusing on one part of the energy equation is like leaving money on the table for something you’re trying to buy. Of course you want to remove the heat in the summertime, but you also want to remove the humidity. And an ERV accomplishes both of these goals.” Going further Marks added that, “the work your AC has to do to remove the moisture is in some cases far in excess of what it takes to cool [the dry bulb temperature] down. An ERV has a special membrane in it and it’s unique in that it enables moisture to pass through it. Air runs through [the membrane flutes] and transfers heat via sensible conduction but it also passes moisture via diffusion and that’s different from an HRV. An HRV is just a plate-on-plate heat exchanger with very thin material.” How Are ERVs and HRVs Similar? After discussing the differences between ERVs and HRVs, the topic moved to the similarities. Marks kicked off the conversation with a quick summary. “They both recover energy. They save you money on your power bill. They both have balanced ventilation. Usually they both filter the air. The big core difference is the heat exchanger. Is it just exchanging sensible heat? That’s an HRV. If it’s exchanging sensible and latent heat, then it’s an ERV.” Adding to this was Agopian. “A recovery ventilator, regardless of whether it’s an ERV or an HRV, is used to displace air and filter the outdoor air that’s coming in.” Along these lines, he noted that most HRVs use only Minimum Efficiency Reporting Value (MERV) 8 filtration and ERVs today have higher capabilities and they can adopt MERV 13 filtration. For background, MERV ratings measure a filter’s capacity to capture particles of varying sizes. For example, a MERV 8 filter only captures 20% of the smallest particles while a MERV 13 filter captures 50%. Plus, MERV 13 filters are more effective at capturing larger particles. However, the key difference between the two systems—humidity control—was emphasized by Agopian. “An ERV gives you a little more help to dehumidify within the space as compared to an HRV that doesn’t offer anything in terms of humidity control. With an ERV it’s a lot more efficient than not.” Along those lines, Agopian addressed outdated thinking about ERVs vs. HRVs. “It used to be thought that ERVs are great only down south where there’s high humidity. Well that’s true, but as we go north, and even in Canada, we see a lot of humidity as well. Does it get as humid in New York City, Montreal, and Toronto as it does in Seattle? Yes. We do need ERVs in the summertime, and now more than ever, we have some humidity within spaces in the wintertime in the northern regions. An ERV will allow you to keep that humidity indoors.” Building on this point was Marks. “The misconception is, ‘I have an HRV because I live in a cold climate and an ERV doesn’t provide much value.’ But the wildcard is whether you are conditioning air in the winter. If you have a humidifier, you’re evaporating water and adding a cooling load to heat up your house to turn that water into water vapor. If you ventilate, you send that water vapor outside and bring in cold air that will dry out your home. Conversely, an ERV resists humidity changes.” What Are the Main Negatives When Comparing ERVs and HRVs? The conversation then delved further into the differences between ERVs and HRVs, digging deeper into the main negatives. Marks explained, “When you value fresh air, you bring in more of it and you have to do energy recovery. An HRV recovers energy, but does that solve the entire problem? We know an HRV can’t mitigate moisture coming into your home. An ERV is a great tool to bring in fresh air, recover humidity, save money and be energy efficient and healthy at the same time.” Discussing the operational differences between ERVs and HRVs was Agopian. “Number one, because you’re not transferring humidity in an HRV, in wintertime humidity does condense and freeze up. All HRVs have an active defrost cycle in northern areas with snow. This means that for a period of time, ice needs to be melted and you have no ventilation. In addition, because you have defrost, there’s a pipe dangling down from an HRV. Sometimes drains clog and you have a pool of water in your basement. An ERV is almost maintenance-free as compared to an HRV. Further, the goal as we move forward from all cognizant authorities is continuous ventilation. Thus, they’re saying to use an ERV everywhere.” Summing up the podcast was Marks. “If you’re operating at a temperature far below the freezing point, frost will start moving across the HRV heat exchanger until it’s completely blocked. That’s why HRVs have a defrost cycle, during which there’s no more heat recovery. It’s just exhausting air to thaw out the HRV. If you wanted to have equal performance, then you should oversize the HRV because it’s not really doing any recovery during defrost. The winter performance of an ERV is far superior to an HRV.”

Reach and audience

Public platform figures. Ratings count people who left a rating, not total listeners.

Apple Podcasts (US)

4.0 / 5

4 ratings

Spotify

5.0 / 5

2 ratings

Contact IAQ IQ: Indoor Air Quality and You

Guest appearances

Books guests

Based on episode analysis; this does not confirm that the show is currently accepting guests.