Lab Ventilation Energy Use and COVID

[russ_watters]

I'm a basic chemist and sustainability champion trying to use essential principles in ventilation safety to provide optimum ventilation for vapors, gases, and even infectious aerosols (e.g. SARS Co-V). Laboratories have 5x the energy demand per M2 as offices, so conservation there makes a big difference. Scientists need to be advocates for conservation in their workplace--the lab! And you can still do great science! See http://mygreenlab.org; University of Colorado Green Lab program has been going for 10 years!

Welcome to PF! I'm an HVAC engineer and I actually gave a talk/round-table with the founder of your organization a few years ago:
https://www.westchesterbiotechproject.org/innovation-in-research-2017

One factoid I give on labs that speaks to what people know is that a single 8' constant volume fume hood requires more energy to operate than the average house.

Ventilation safety is clearly an important issue during COVID, if a bit tangential to lab ventilation safety. And unfortunately/ironically a lot of the changes/optimizations being made for COVID transmission mitigation increase energy usage (such as increasing outdoor air fractions and increasing filtration levels).

 

[Rooner1]

thanks for the greetings Russ.
You are in great company if you spoke with my good friend Allison. She is amazing, and brought much of the early work in Green Labs to a professional level. The movement continues to mature and blend with core mission of research and operations, as it must. Is there a recording or transcript of your talk?
Some of the efforts to get ventilation to protect from the virus are misguided, some well founded. The basics to prevent near-field transmission of aerosols, like masks and social distancing, are quantitatively the best approach, as no examples of infection from recirculated air have been documented. During infectious times the laboratory is probably the safest place to be if it is run with 100% exhaust and 4+ air changes per hour (ACH).
As you likely know, many labs are way out of tune, and running at 8-12 ACH. Thus, one of the biggest quantitative things a scientist can do in their career to save energy and associated GHG is to be a champion for ventilation efficiency in their own laboratory.

 

[Rooner1]

To be more accurate, an 8' fume hood blows 1200+ cubic feet per minute when open, and 400 CFM when closed (if the HVAC modulates). The amount of energy it takes to condition that air from outdoor ambient is quite astounding, and more likely equivalent to 3 houses.
If you work in a building with a modulating HVAC, be sure to have a "close the sash" campaign to have a quantitative impact on energy use. Some intuitive and compelling sticker-stripes that go on the side jamb of fume hoods can be purchased at cost from the University of California, Davis Reprographics on-line store. Thousands of colleagues around the world have already done so. Contact me if you cannot find the link through a search.

 

[russ_watters]

Is there a recording or transcript of your talk?

I know it was recorded, but unfortunately I don't know where one could access it -- it's not on the website.

Some of the efforts to get ventilation to protect from the virus are misguided, some well founded. The basics to prevent near-field transmission of aerosols, like masks and social distancing, are quantitatively the best approach, as no examples of infection from recirculated air have been documented. During infectious times the laboratory is probably the safest place to be if it is run with 100% exhaust and 4+ air changes per hour (ACH).

Agreed; there is no need for more than that in a lab for COVID mitigation. It's offices where the ventilation rate is being increased for COVID. Typically they run <1 ACH (ventilation) and maybe 6 re-circulated (10%-20% ventilation). For some systems it is possible to do up to 100% ventilation, weather permitting. I have a client that re-programmed their systems to do that.

As you likely know, many labs are way out of tune, and running at 8-12 ACH. Thus, one of the biggest quantitative things a scientist can do in their career to save energy and associated GHG is to be a champion for ventilation efficiency in their own laboratory.

Yes, I've done a considerable amount of work on this issue.

To be more accurate, an 8' fume hood blows 1200+ cubic feet per minute when open, and 400 CFM when closed (if the HVAC modulates). The amount of energy it takes to condition that air from outdoor ambient is quite astounding, and more likely equivalent to 3 houses.

The rule of thumb I use for my region is $5 / CFM / year ($6,000 / yr) and google tells me the average house spends about $2,200 a year in energy costs, so yes, it would be closer to 3.

If you work in a building with a modulating HVAC, be sure to have a "close the sash" campaign to have a quantitative impact on energy use. Some intuitive and compelling sticker-stripes that go on the side jamb of fume hoods...

What I've seen is that it takes a disheartening amount of effort to change behaviors. I've been part of studies where the sash positions are are noted by security at night and then shared with lab managers; almost like a competition/scorekeeping. It does work, but as soon as you relax your effort the scientists go right back to leaving them open. I much prefer automatic sash closures.

 

[Rooner1]

I know it was recorded, but unfortunately I don't know where one could access it -- it's not on the website.

Agreed; there is no need for more than that in a lab for COVID mitigation. It's offices where the ventilation rate is being increased for COVID. Typically they run <1 ACH (ventilation) and maybe 6 re-circulated (10%-20% ventilation). For some systems it is possible to do up to 100% ventilation, weather permitting. I have a client that re-programmed their systems to do that.

Yes, I've done a considerable amount of work on this issue.

The rule of thumb I use for my region is $5 / CFM / year ($6,000 / yr) and google tells me the average house spends about $2,200 a year in energy costs, so yes, it would be closer to 3.

What I've seen is that it takes a disheartening amount of effort to change behaviors. I've been part of studies where the sash positions are are noted by security at night and then shared with lab managers; almost like a competition/scorekeeping. It does work, but as soon as you relax your effort the scientists go right back to leaving them open. I much prefer automatic sash closures.

\

Yes, behavior is very difficult to change, and the stickers work pretty well over the long term. Some students at MIT developed a "MASH" alarm which had excellent compliance (under 10% open), and cost about $15 to make. The University of Alabama Birmingham is also using them. INstallation is under $50 per hood, I believe. At our work we are generally against auto sash closers because of complexity, first cost, and maintenance costs. Still searching!

 

[sophiecentaur]

During infectious times the laboratory is probably the safest place to be if it is run with 100% exhaust and 4+ air changes per hour (ACH).

Which makes conditions on public transport pretty laughable, imo. There are many more passenger changes per hour than air changes and so many of them either don't wear masks or have their own interpretation of what 'wearing' means.

As far as I can see, any running cost would be acceptable from now until the R number is very low. The real cost of the totality of infected people and the economic impact of lockdowns would be less than moderate improvements in ventilation.