High-performance multimode elastocaloric cooling system.

Developing zero-global warming potential refrigerants has emerged as one area that helps address global climate change concerns. Various high-efficiency caloric cooling techniques meet this goal, but scaling them up to technologically meaningful performance remains challenging. We have developed an elastocaloric cooling system with a maximum cooling power of 260 watts and a maximum temperature span of 22.

Fatigue-resistant high-performance elastocaloric materials made by additive manufacturing.

Elastocaloric cooling, a solid-state cooling technology, exploits the latent heat released and absorbed by stress-induced phase transformations. Hysteresis associated with transformation, however, is detrimental to efficient energy conversion and functional durability. We have created thermodynamically efficient, low-hysteresis elastocaloric cooling materials by means of additive manufacturing of nickel-titanium.

Electrochemical ammonia compression.

Every year a large amount of ammonia is mechanically compressed with a low efficiency (∼65%) as an environmentally friendly chemical for fuel storage, transportation, food preservation and air conditioning. Electrochemical compression with a high efficiency (93%) offers an opportunity for substantial energy savings. But ammonia is never considered electrochemically compressible because of the known decomposition at high applied potentials.

Energy consumption analysis on a dedicated outdoor air system with rotary desiccant wheel.

A dedicated outdoor air system (DOAS) with rotary desiccant wheel is the combination of a desiccant dehumidification system and a vapor compression refrigeration system. An energy consumption model of this hybrid DOAS is established for its analysis. Coefficient of performance, , is appropriately defined for evaluation on performance of the hybrid DOAS.