"The discussion of energy consumption for cryogenic & combined #DirectAirCapture systems is explored in the newly published thesis."ποΈ
Details are discussed in aπ§΅β¬οΈ
1/10
In this novel approach, "a thermodynamic model was constructed using psychometric theories to model the #desublimation of CO2 in a #DAC system. The system was modeled
to include a precooling heat exchanger & a deposition chamber where the desublimation
of CO2 occurs."
2/10
3οΈβ£ base systems studied:
πΈ NC (no precompression/turbine recovery)
πΈPC (precompression only)
πΈTR (precompression & turbine recovery)
at 3οΈβ£ different compression ratios, n=400, 800 & 2000.
Then, a combination #DAC system, PSA, was modeled."
3/10
"A dual-column, 4οΈβ£-step Skarstrom Cycle PSA (pressure swing adsorption & cryogenic distillation) unit was analyzed using Extended Langmuir Models & the
ideal gas law to simulate a CO2 conc. prior to the deposition chamber. The NC & PSA systems were assessed at Tamb= -50β¦C."
4/10
This study finds that "while increasing the compression ratio of the system, there is no net energy benefit when capturing CO2 given the current state-of-the-art in commercial compressor & #cryocooler capabilities."
5/10
"The assessment of the efficiency of a precooler versus TR finds that it is more advantageous to utilize a heat exchanger precooler than precompression with turbine recovery in a #DAC system. Combining DAC systems may yield a more efficient system."
6/10
"PSA combined with cryogenic capture is less energy intensive than cryogenic capture alone. In a combined #DAC system with PSA and cryogenic distillation,
the PSA unit has a significantly lower energy consumption than the #cryocooler."
7/10
"Increasing the concentration of CO2 entering the deposition chamber significantly decreases the required energy consumption of the #cryocooler."
8/10
Read the complete #Doctoral#Thesis entitled: "Atmospheric Carbon Capture: A Review on Current Technologies and Analysis of Energy Consumption for Various Direct Air Capture (DAC) Systems" here β¬οΈ commons.erau.edu/edt/728/
π¨Greenhouses can grow food in extreme climates, but they often depend on fossil-derived COβ inputs to maximize crop yields.
New study investigates whether Direct Air Capture (#DAC) could replace those emissions-intensive COβ sources by capturing C directly from air.π§΅1/13
2/ Researchers modeled a 1-ha sealed high-tech greenhouse in Jeddah, Saudi Arabia producing cherry tomatoes & lettuce under hot-arid conditions.
The system maintained ~1000ppm COβ conc, which are required to sustain high crop productivity in climate-controlled desert agri.
3/ The study evaluated two adsorption-based DAC systems:
β’ temperature-vacuum swing adsorption (TVSA)
β’ moisture-swing adsorption (MSA)
Both were benchmarked against conventional trucked liquid COβ enrichment currently used in commercial greenhouse operations
π¨Monthly Solar Geoengineering Updates (April'2026)π¨
From EU calls for an #SRM deployment moratorium & WHO-linked health-centered governance report, to Stardust publishing its own SRM rules, key SRM headlines you need to know from past month:
π
The private SRM company publishes voluntary rules and safety guidelines, but experts raise concerns over transparency, unknown aerosols, and private control of planetary-scale interventions.
1/12
2οΈβ£ WHO-linked report calls for health-centered SRM governance:
A pre-print urges SRM governance centred on human health, equity, and Global South inclusion, stressing SRM must never replace emissions cuts (βnon-substitutionβ principle).
π¨Is direct air capture (#DAC) really worth the investment?
A new Nature Climate Change study shows that investing in wind & solar delivers 2-3Γ greater combined climate + health benefits than direct air capture across most U.S. regions, under the same budget.
Detailsπ§΅1/11
2/ DAC is often promoted as essential for net-zero, removing COβ directly from the atm. But most studies assess it in isolation, asking: βDoes it work?β
This study asks a policy-relevant question:
βWhat are we giving up by funding DAC instead of alternatives?β
3/ Researchers modelled cost-equivalent investments across 22 U.S. regions (2020β2050), comparing:
Direct Air Capture vs Utility-scale wind & solar
Critically, they evaluated COβ reductions + air pollution + health impacts.
π¨What happens to tropical rainforests as COβ rises?
New research shows higher COβ boosts tree growth & C uptake by pushing roots to aggressively mine scarce phosphorus.
This strengthens the C sink now, but depletes nutrients, ultimately limiting long-term C storage.π§΅1/11
2/ Scientists tested this in the Amazon by exposing forest patches to higher COβ (future-like conditions) and tracking how trees, roots, and soils responded over time.
3/ Step 1: More COβ β faster photosynthesis
Trees produce more sugars, grow faster, and pull more COβ out of the air.
π¨Green roofs + enhanced rock weathering (#ERW) could turn cities into carbon sinks.
A new assessment finds Europeβs rooftops could remove tens of millions of tonnes of COβ by 2060, with global potential reaching hundreds of MtCOβ/yr under ideal conditions.
Detailsπ§΅1/12
2/ The work is a conceptual, literature-based assessment combined with geochemical scaling.
It estimates COβ removal using theoretical maximum reactivity (100% mineral conversion) and extrapolates across urban roof availability in Europe and globally.
3/ Roof availability is a key input:
The study uses estimates that roofs cover ~30β32% of urban land area, and up to ~50% of impervious surfaces in dense cities, highlighting a large, currently underused surface for carbon removal deployment.
π¨A new study details that the climate value of algae & cyanobacteria lies not in COβ uptake alone, but in their capacity to generate long-lived, chemically recalcitrant C compounds, such as algaenan & carbonates that may contribute to durable sequestration pathways.
π§΅1/11
2/ The study adopts a conceptual synthesis framework, integrating biochemical & geochemical evidence to examine carbon fate post-photosynthetic fixation, moving beyond uptake rates to study the thermodynamic and structural persistence of biogenic carbon.
3/ It constructs a functional distinction between:
1) Labile carbon fractions, which are rapidly cycled through microbial respiration
2) Recalcitrant fractions, which resist degradation & contribute to long-term carbon storage across terrestrial & marine systems.