Rocket Stove

by Hein Kramer

1 Jan 2016

A highly efficient stove made almost entirely from reclaimed materials, Hein Kramer's rocket stove can easily reach 1000 degrees and is virtually non-polluting.


Rocket Stove - Hein Kramer's rocket stove is highly efficient and almost entirely made of reclaimed materials. Lisanne Groenewoud

The Rocket Stove

When you visit our restaurant, you will see a strange-looking stove. The large metal creation is the brainchild of Hein Kramer and is called a ‘rocket stove.’

Through a small window at the front of the stove, the first chamber can be seen in which hot glowing logs are slowly being devoured by the heat. Attached to the back of this are two stacked metal barrels with a fan on top, spinning with the rising hot air. The chimney of the stove comes out of the two barrels and travels first through a bench clad with scrap marble, before moving to the roof of the greenhouse.

The marble takes most of the heat from the air before it leaves the chimney. By using this system, only a very small portion of the initial infernal temperature inside the vortex is allowed to escape, making it an efficient and ecologically friendly stove.


Hein was inspired by hippies in the 1970s who turned oil drums into highly efficient stoves. These stoves were used to burn wood found among the undergrowth of the woods so that no trees would have to be cut down.

“When I saw these stoves I thought, 'This is interesting. I can improve this.'”

He laboriously set to work, using reclaimed materials such as old Heineken barrels and metal parts found on the scrapheap to create the maze of chambers and furnaces you see today. The stove is easily able to reach temperatures of 1000 degrees.


Rocket Stove - Hein Kramer working on his rocket stove: “It’s an on-going process, like going somewhere but discovering something new and fun along the way. It’s about the adventure an not so much about the destination.”

How it works

“The fire, unlike in normal stoves, doesn’t burn upwards, but moves from the first frontal chamber backwards to a cylindrical chimney inside the barrels where the fire gets an extra boost of oxygen from a small hole in the bottom. Then it swirls upwards until it can’t go any further so it falls down around the inner chimney before it can exit.”

If you peep through a small hole in the top of the barrels, it is as if you are looking right into the core of a volcano.

“Because the fire starts spiralling through the inner chimney it burns for longer, which means that more and more heat is being generated. This is more efficient than traditional stoves. The swirling of the fire makes sure that the heat generated can’t escape through the chimney.

I wound a pipe around the inner cylinder through which water is being pumped. The fire vortex heats the water that, in turn, heats several radiators. This way the heat is being taken from the stove and distributed through the space, rather than dispersed through the chimney.

What escapes through the chimney is only 30 degrees and the smoke you see is simply water vapour, as all particulate matter is destroyed by the intense heat inside the stove.”

Work in progress

Hein’s rocket stove is still a work in progress. “It’s an on-going process, like going somewhere but discovering something new and fun along the way. It’s about the adventure and not so much about the destination.”


HOT - The rocket stove can easily reach 1000 degrees, touching it is not recommended.

The Rocket Stove at Mediamatic ETEN.

Check our calendar for extended opening hours and events.