In January 2023 we set up one of the most ambitious greenhouse experiments for enhanced rock weathering. Since then a lot of things have been going on, including four near-disasters involving frost, fire, water and hail.

Here is a photo album diary of the first 7 months in the Carbdown greenhouse.

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Februar 11th 2023

The grass plants have started!

February 23rd 2023

The 3rd generation prototype of our automated fluxmeters is being tested in the greenhouse. This prototype is based on LEGO Mindstorms robotics.

March 1st 2023

For the first time we are taking leachate water samples and measure metrics like pH, electrical conductivity and total alkalinity, among others. This will be done once a month for all 350-400 pots.

March 12th 2023

Our 300 lysimeters got their first haircut: every few weeks we cut down the grass/biomass, dry it and store the leaves.

March 13th 2023

For each of the pots we collect (and accumulate) the hay separately for later weighing, inspection and analysis. Drying is done in small paper bags using our drying oven at 60°C for >48 hours.

March 13th 2023

Near disaster #1: Hail storm! A strong hail storm luckily did not damage the glas roof.

March 15th 2023

Progress was hampered a bit when our trustful old Kärcher vacuum cleaner sent white smoke signals, and had to be replaced.

April 23rd 2023

Near disaster #2: Frost! We burnt through the heating oil in the tank faster than anticipated and had to organize an emergency refill so our plants would not get hurt.

May 2nd 2023

The 4th prototype generation of our automated fluxmeters is ready for testing. This one already uses the controller and the CO₂ sensor of the final system.

May 26th 2023

Near disaster #3: No Water! The irrigation water system broke down and the pressure tank had to be replaced a few days later. In the meantime we had to come up with a makeshift irrigation system for our 350 pots.

June 16th 2023

We are engineering/building the 5th, heavily upgraded generation of our robotic fluxmeters for our greenhouse experiment. With 50 of these fluxmeters we will be able to monitor the CO₂ efflux from our 350 ERW experiments around the clock.

June 27th 2023

Our small army of custom fluxmeters (generation 5) for the greenhouse is being built. We are hand-building 50 of them in the CEO’s garage. Since the first protoype wie have continuously upgraded the sofwtare (we are now on version 5.80 of device firmware and cloud architecture) to make the devices autonomous and mostly failure-proof (otherwise running 50 or more of these boxes would quickly become a nightmare).

June 30th 2023

Our enhanced weathering experiment is now 150 days old. 350 lysimeters with 70 variations of 15 soils and 11 rock dusts are happily weathering while we take samples, measure leachate waters and monitor hundreds of metrics 24/7.

July 3rd 2023

We have moved our robot army to the greenhouse where we try to measure the speed of enhanced weathering with rock dusts like basalt, dunite or diabas on soils.

July 16th 2023

Every 2-3 days we groom the grass of the next 50 lysimeter experiments and then move over our robot army, a set of fully autonomous scientific fluxmeter instruments which measure CO₂/water-vapor flux, light and air pressure/temperature every 6 seconds. The transfer process takes >2 hours.

July 20th 2023

Near disaster #4: Fire! A motor of the aging roof-window-mechanic had caught fire. Luckily the fire did not spread to the sun shades and nothing else was harmed.

August 4th 2023

6 months of biomass/grass sampling in the greenhouse: More than 1000 dried gras/biomass samples. For each one of the 350 lysimeter pots and for each cutting event stored in an individual paper bag for later analysis.

August 28th 2023

Our grass plants needed some nitrogen, so we added a few milligrams of nitrogen fertilizer to each lysimeter (highly diluted in lots of water).

September 26th 2023

We have some illegal aliens in some pots, every once and while we need to remove rampant weeds.

October 4th 2023

A film team was in the greenhouse filming all the activities and details of our work.