Project details

Location: Haarlem - Kennemerplein

Cleaning up potential: 34,000 kg CO₂

In the centre

On the Kennemerplein

Behind the station, a kiss and ride strip has been constructed with greenSand olivine-rich semi-pavement.
This weathers and then incorporates CO₂ when it weathers, especially after a rain shower. The more you walk over the stones, the faster it clears CO₂.

In the Waarderpolder

A walking path and exit strip

At the Jacques Meuwissenweg is a beautiful footpath of greenSand Olivine. And our CO₂ clearing stones are also located on the exit lane at the car park on Claes Tillyweg.

Maarten and Jelle tell

* The video talks about olivine trails. This refers to paths of greenSand Olivine, which is made from olivine-rich rocks.

The story of Maarten and Jelle

The municipality of Haarlem attaches great importance to sustainability. This enabled the young Haarlem residents Maarten Hulsman and Jelle Brans to realize their dream of having CO₂ clearing paths built in their municipality. Below you can read their inspiring story.

Grandpa's knowledge

Maarten says that he was looking for ways to get CO₂ out of the air for a profile paper. When he visited his grandfather, he said that there are also rocks that remove carbon dioxide from the atmosphere. Maarten thought this was an interesting fact and delved into the matter of the weathering of rocks. He came across the publications of Professor Olaf Schuiling, who saw the mineral olivine as the way to solve climate problems.


Maarten really liked it. He persuaded Jelle to jointly publicize the solution to the climate problem. Starting in their own hometown. In November 2019 they pitched their plans in the Haarlem Initiative Café. Here all residents can put forward their ideas for the city. With their pitch and well-executable plans, the two won and earned an amount of 5,000 euros to carry out their plans.


Three paths have now been constructed in Haarlem with olivine-rich rocks of the greenSand. Maarten and Jelle have meanwhile started their studies. They partner with greenSand to promote the solution that has been used by the Earth for billions of years. So that more and more people can help clean up the surplus of CO₂. Maarten and Jelle say: "First we go for Haarlem and the surrounding area, then the Netherlands and then across the border."

Contribute your bit

Clean up CO₂ yourself

Help the Earth create more surface area. Discover all Olivine products.

Compensate your CO₂

We scatter the Olivine for you. In this way we create more surface area together.

Become a co-owner

Become part of the solution. Buy a registered share in greenSand.

from €15