TEL: 1-608-238-6001 Email: greg@infinityturbine.com
Infinity Turbine PowerBlock 10 MW Supercritical CO2 turbine generator power supplying 10 MW of power for AI Data Centers and charging Tesla MegaBlock... More Info
|
Using Pressurized CO₂ and Dry Ice for Cold Energy Storage What if you could store cold like you store heat? This article investigates whether solar or geothermal-heated CO₂ can be converted into dry ice for long-term thermal energy storage—and what losses occur along the way. |
|
Using Pressurized CO₂ and Dry Ice for Cold Energy Storage: A Viable Alternative As the global demand for efficient cooling and energy storage rises, researchers and engineers are exploring new ways to store cold energy—a less commonly addressed counterpart to thermal (heat) storage. One novel concept proposes using solar, thermal, or geothermal energy to pressurize carbon dioxide (CO₂), then release it under controlled conditions to form dry ice, storing cold energy for later use. This article examines whether this method is viable, and how much CO₂ is lost during the process.How the Process Works1. Heat and pressurize CO₂:Solar thermal, geothermal, or waste heat energy is used to compress CO₂ into a supercritical or high-pressure liquid state.2. Release and expand CO₂:The pressurized CO₂ is then allowed to expand and drop in pressure, either by venting or by directing it through a nozzle into a collection chamber. This rapid expansion causes a portion of the CO₂ to solidify into dry ice.3. Capture dry ice in insulated medium:The dry ice can then be stored in bags, tanks, or insulated containers for later use in cold storage, refrigeration, or chilled water systems.Thermal Cold Energy Storage PotentialDry ice sublimates at -78.5°C, making it a highly concentrated form of cold energy.It can be stored in insulated environments with relatively low loss for hours to days, depending on insulation and volume.Upon sublimation, it absorbs 571 kJ/kg (136 BTU/lb)—useful for passive cooling.CO₂ Loss in the ProcessCO₂ loss depends on system design, especially the ability to capture and recirculate gas during sublimation.In open systems, 100% of the CO₂ will eventually be lost to the atmosphere as it sublimates.In closed-loop systems, it is possible to recapture the gas after sublimation and recompress it, reducing losses significantly.However, the initial release and solidification process can result in 30 to 50 percent loss depending on how well the system is insulated and enclosed.Pros and ConsAdvantages• High-density cold storage in small volumes• Leverages renewable heat sources (solar or geothermal)• Portable and modular• No electricity required to discharge cooling• No moving parts in storage phaseChallenges• CO₂ venting if not recaptured• Requires insulated containment• High energy input for pressurization• Safety concerns with CO₂ in confined areas• Not suitable for very long-term storage without continuous insulation or active managementUse Case Fit| Use Case | Suitability || ----------------------------| ----------|| Off-grid cold storage | High || Data center emergency cooling | Medium || Portable refrigeration units | High || Grid-scale cooling buffers | Low–Medium || Long-term seasonal cooling | Low |ConclusionUsing heated and pressurized CO₂ to create dry ice for cold storage is an innovative approach to storing thermal energy in the form of cold. It is technically feasible, particularly when paired with renewable energy sources like solar thermal or geothermal. However, unless used in a closed-loop system, CO₂ losses to the atmosphere can be significant.As a short-term, high-density cold storage solution, especially in off-grid or portable scenarios, this approach offers intriguing potential. For longer-term or large-scale storage, however, the energy input, gas loss, and handling complexity may outweigh its advantages unless system designs evolve to become more efficient and sealed. |
| CONTACT TEL: 1-608-238-6001 Email: greg@infinityturbine.com | AMP | PDF |