Do you ever get ridiculously sleepy in the middle of the afternoon?
Like, not normal sleepy.
I mean the kind where you’re sitting in a lecture, genuinely trying to pay attention, and suddenly your eyes are closing on their own.
And it is ALWAYS that one lecture scheduled at peak afternoon.
It doesn’t even matter how interesting the lecture is. At 2 PM, my brain has apparently decided that learning is no longer part of the day's agenda.
I looked around and realized it wasn't just me either.
Someone was asleep. Someone else was fighting for their life trying to keep their eyes open. Another person was staring at the professor while very clearly thinking about… well, absolutely nothing.
So there were only two possible explanations:
Either we had a collective inability to concentrate…
Or the environment was conspiring against us.
Now, I personally believe I am perfect and incapable of incapacity, so obviously I chose option two:
Find a way to blame the environment.
So I went down a Google rabbit hole.
And turns out, it actually can be the environment.
Not in the dramatic “the classroom is poisoning us” way.
But there is something called Sick Building Syndrome (SBS).
Basically, people can experience things like fatigue, headaches, dizziness, irritation and difficulty concentrating while spending time in a particular building, especially when indoor air quality and ventilation aren't great.
That, for the first time made me think about my classroom because it sounded suspiciously familiar.
With the windows shut and the AirCon working overtime with the poorly working vents,it sure does get stuffy.
Every breath adds more CO₂. As levels climb, that stuffy room can come with headaches, fatigue, sleepiness and difficulty concentrating.
But what does “ppm” actually mean and why do those numbers matter?
And it isn't just one study.
So while you're fighting to stay awake, the room might not exactly be helping.
A randomized study of 162 college students found that reducing indoor particulate pollution with air filtration improved scores on some standardized tests.
And it’s not just about what’s floating in the air. It’s also about what happens when that air stays trapped around us.
A 2025 study of 205 university students in Malaysia looked at indoor air quality and Sick Building Syndrome symptoms across different classrooms. SBS symptoms were reported more often in lecture halls than tutorial rooms, and factors including CO₂, particulate matter, carbon monoxide and fungal levels were associated with symptoms depending on the classroom type.
The researchers aren't saying, “CO₂ made these students fall asleep.”
It’s more complicated than that.
But it does suggest that the room we're sitting in might matter more than we think.
And that made me look around my classroom a little differently.
Because maybe the question isn't just:
“Why am I so tired?”
Maybe it's also:
“What is going on with the room?”
And this isn't just about CO₂.
Indoor air isn't exactly empty.
There can be particles, pollutants, chemicals, dust, humidity and biological contaminants floating around with us.
And some research has found links between indoor air quality and symptoms like fatigue, headaches and irritation.
So maybe half the class isn't asleep because we're lazy.
I’m not saying it’s the air.
I’m just saying I’m no longer blaming the professor.
Okay, so what do we do?
The obvious answer would be:
Go outside.
Get some fresh air, sit in a garden surrounded by greenery.
Great.
I'll just tell my professor:
“Sorry, can't attend today's lecture. I'm off to find a forest so my brain can function.”
Very practical.
The problem is that most of us spend a huge amount of our day indoors anyway, I’m talking like 90% of our time indoors, atleast that’s what US EPA says.
We complain about being indoors while continuing to be indoors.
So telling everyone to simply “go outside” isn't really a solution.
It made me (Technically company's founder) wonder about something else:
What if we made the spaces we're already in better?
Maybe nature doesn't always have to stay outside.
This is where I ended up discovering microalgae.
Microalgae are tiny organisms that have been photosynthesising for billions of years. Give them light, water and CO₂, and they get to work.
At AlGreen, we're interested in what happens when we take that very old piece of biology and rethink how it can be used indoors.
That's the idea behind VAYU, our compact living microalgae system.
It's a small, visible way to bring photosynthesis into the spaces around us and explore how living systems can play a role in the way we think about indoor air and carbon capture.
It's not a replacement for ventilation.
And no, we're not claiming it will magically keep you awake through your 3 PM lecture.
(Although I did write this in the afternoon with VAYU sitting right next to me, so I have my own theories.)
But it does raise a pretty interesting question.
We've spent decades making our indoor spaces smarter, more connected and more automated.
What if we also made them a little more alive?
And if you ever find yourself falling asleep in a perfectly good lecture again…
Maybe don't blame yourself immediately.
Find other things to blame.
Like the environment.
You know, for scientific purposes.
Curious about the little living system behind this idea?
Written By :
Krisha Mehta, BD & Marketing Intern
