The Science Behind The BioLite CampStove

May 14, 2020
Filed Under: gear orientation

A Mini STEM Lesson From The BioLite Team

In This Lesson

Total Estimated Time For Lesson: 30-45 minutes, 1.5 hours with guided burn

How Does The CampStove Work?

In this video, BioLite engineer Ben walks you through how we get wood to burn very efficiently and how we turn heat from the fire into electricity.

Energy In Many Forms: Heat, Electricity, and the CampStove

One of the coolest things about the CampStove is its ability to help you extract energy from unexpected places and turn it into different kinds of energy for different purposes.

Those sticks lying around in your backyard? They’ve got energy inside them, waiting to be used - same deal if you’re using wood pellets! The CampStove unlocks that energy by combusting those sticks as fuel (combusting = burning) which creates heat. The heat of your fire is a form of energy that you can use to boil water, make a meal – or roast a nice marshmallow.

But what if you needed energy to charge your phone, or your watch, or maybe a headlamp? Putting your watch in the fire is definitely a bad idea, and it definitely won’t charge it! So it’s time to transform that energy again into something else: let’s turn it into electricity.

As Ben mentioned in the video, the CampStove has something inside of it called a thermoelectric generator (aka a TEG). Have you ever used a solar panel? Well, what a solar panel does with the sun…a TEG does with heat! It takes one form of energy… and turns it into another form of energy. So while you’re roasting your marshmallow or boiling your water, a small portion of the heat of your fire gets converted through the TEG into electricity which does two neat things:

  1. It powers the internal fan in the CampStove (which helps it burn without nearly any smoke)
  2. It flows to the USB Port, and that’s where you can access that electrical energy to charge your phone, watch, or headlamp!

And it all starts with a handful of sticks -- Pretty cool, huh?

How Many Scientists* Does it Take To Make a CampStove?

*and anyone else using science, technology, engineering, and mathematics to help make our stove come to life!

Mindy BioLite's Industrial Desinger
BioLite Engineers inside the lab

Did you know we have an actual rocket scientist on the BioLite team?

Seriously! We do! (It’s Ryan, and here he is giving a lab tour ← BONUS VIDEO!)

Our team of engineers and designers come from a wide background of experiences and studies. Together, we apply our collective knowledge to create products with the goal of making them easy to use, reliable, and efficient. This means a lot of hard work from a lot of teammates.

Here are some of the different roles that go into making something like the CampStove:

Industrial Design & Mechanical Engineering: These team members work on the physical structure of the CampStove: how it looks, the materials used, and how different pieces come together in both the manufacturing process and in the operation of the actual unit. A lot of early work may start with hand-drawn sketches and then it moves into digital models known as renders, which help the team understand how the product might look in a three-dimensional space. This often means using computer-aided design (aka CAD) software to help create technical drawings and illustrations. Industrial designers and mechanical engineers work closely with the combustion team to understand how the physical design impacts burn performance and with the electrical team to ensure that the design can safely house the electrical components required for operation.

See the hexagon metal pattern on the outside of the CampStove burn chamber? That is called Heat Mesh and it got designed using CAD software!

Combustion Engineering: These team members work closely with the industrial design and mechanical engineers to ensure that our CampStove is delivering on its promise of burning without nearly any smoke and successfully converting some of its heat into usable electricity through the thermoelectric generator. The combustion team uses tools like thermal imaging to measure temperatures inside the CampStove and see if there are hot spots, cold spots, or a uniform temperature (hot tip: we WANT a hot temperature across the entire burn chamber, and we rely on airflow from our fan to help make that happen). Ever go camping and have to shuffle around a campfire that has lots and lots of smoke? That smoke means the fire isn’t burning as efficiently as it could be. We’re on a mission to fix that.

Think about it this way: when you go for a drive and get stuck behind an old truck that has a bunch of smoke coming out of its tailpipe, it probably means that truck is ready for a trip to the mechanic, right? Well guess what – a super smoky fire is just a fire that needs a mechanic to help it run better! And in our case, those “mechanics” are our combustion engineers. To make sure our stove is fully tuned up and burning well, the team runs tests in our burn lab and uses a special ventilation hood to measure the emissions (aka the smoke) that come off our CampStove. That helps us learn quickly if the system and design is working properly.

CampStove 2 Thermal Technology

See the holes inside the burn chamber of the CampStove? When the fan turns on, those become air jets, forcing air into the fire at specially located points. The combustion engineers worked closely with the mechanical engineers to determine exactly where those holes should be so that the fire gets properly mixed with oxygen for a super efficient burn (and efficient means all the fuel burns up and turns into flames before it can escape and turn into smoke!).

 

Electrical Engineering: Lots of stuff inside the CampStove needs to talk to each other, and to you, the user. That’s where electrical engineering comes in. This team programs something called a microcontroller, which is essentially a tiny computer, and it lives on a printed circuit board inside of the product. By activating that tiny computer, electrical engineers can tell a light when it’s supposed to flash, command a fan to turn a level up or down at the push of a button, and tell you, the user, how much power you’re generating. And speaking of power, the electrical team also helps regulate the flow of energy inside the CampStove so that you can convert it (when the TEG transforms heat into electricity) and then use it (when you plug something into the USB port) safely and easily.

See the LED dashboard on the orange power pack? The Electrical team works closely with the combustion team to ensure that the performance of the fire is accurately measured and represented by the orange set of LEDs, and that the thermoelectric generator is working properly and producing electricity which is represented by the green LEDs. They also work closely with the mechanical engineers to determine how users can interact with the airflow system, represented by the blue LEDs: with the single button located at the bottom of the power pack, users can push the airflow through 4 different speeds which can impact the intensity of your fire – all that is made possible by electrical engineering!

Engineering Is Awesome.

We asked our team what they love about being an engineer - here is what they had to say:

Anthony I Senior Electrical Engineer

"I loved playing with LEGOs when I was a kid. When you're an engineer, the whole world becomes LEGO. Everything is made from building blocks. Everything can be taken apart, fixed, or built into something new. An alarm clock might be a quartz crystal, display controller, and piezo buzzer. A lawn chair might be 5 pounds of plastic and 2 years of CAD. The objects we use every day all have secret stories to tell, and an engineer is someone who's been listening - and writing."

Melisa I Test Engineer

"I love that an understanding of the basic principles of engineering, design thinking, self teaching, and some scrappiness can give you the ability to take a concept that doesn't exist and make it exist. It's a physical (or digital) representation of the idea that you don't have to accept what's given to you and you don't have to accept the world as it is now. Whether it's making a wacky single-function robot or website for fun, or creating a solution for some under-served problem or population, or recreating the functionality of something that's not accessible to you, just being able to proudly say "I made this thing and it does X, Y, and Z" can be deeply satisfying and empowering."

Robin I Electrical Validation Engineer

 

"I love the way even a little bit of basic knowledge gives you almost infinite ways to repurpose things. I am inspired by up-cycling of old electronics fixing something broken and finding creative ways to modify or hack something to solve a problem as a proof of concept and then the hard work involved to bring a great idea to market."

Optional: Guided CampStove Burn

****Operation Required By An Adult****

Got a CampStove? Well take it outside and fire it up! Here are some pointers on how you can apply this STEM lesson in real-time:

  1. Look at the flame: Do you see it burning and twisting in a vortex, kind of like a tornado? That’s the airflow system hard at work, injecting the fire with oxygen through all those holes inside the burn chamber.
  2. Look at the probe inside the burn chamber: That’s collecting heat to pass through the thermoelectric generator. Do you see a lot of flame or a little flame on the probe? How do you think that is informing the LEDs showing up on the power pack?
  3. Look at the orange LEDs on the burn chamber: How strong is your fire? What happens when you push the button and turn the airflow up? What happens when you turn it down? What happens when you add more fuel to the chamber?
  4. See some green LEDs? Plug in the FlexLight and tap it on! You turned fuel into heat… heat into electricity… and now electricity into LIGHT!
  5. Experiencing any smoke? Two things to investigate:
    1. Have an adult safely adjust the fuel inside the burn chamber with a stick so the 51 air jets can better mix the fire. When you give it a bit more room to breathe, what happens? Are your sticks fully inside the burn chamber or are they extending past the top? Keep them inside so the air jets can reach them!
    2. What kind of fuel are you using? Is it wet or dry? Wet fuel will generally create a smoky situation because it makes it really difficult for temperatures to rise… the higher the temperature, the stronger the combustion.