Mold damage in Department of War (DoW) facilities is costly and disruptive. Effective management of indoor air relative humidity is critical for meeting DoW’s strategic recruitment, deterrence, and modernization goals. Dehumidification plays a key role in the air conditioning (AC) process and can account for >50% of AC energy in humid zones. It also strongly influences perception of comfort. Consequently, an AC system that addresses humidity first can achieve significant energy savings and superior comfort. To efficiently control moisture, a novel Regenerating Desiccant Dedicated Outdoor Air System (ReD-DOAS) will be demonstrated at two DoW facilities in warm or hot, humid zones. A successful project will enable efficient and effective moisture control in DoW facilities through heating, ventilation, and air conditioning retrofit or new construction.

Transaera's ReD-DOAS is expected to reduce space cooling energy consumption in warm- and hot-humid zones by around 45-50% (and more in mixed-humid and cold-humid zones) relative to best-in-class conventional DOAS units. The Transaera ReD-DOAS achieves energy savings without increasing system size or weight (same rooftop mounting curb) by leveraging industry-standard installation and maintenance practices, making it a high-efficiency, drop-in replacement for conventional DOAS units with rated supply airflow of 4,000 to 8,000 cubic feet per minute and capacity of 20 to 40 tons.

Using a novel solid-desiccant material called metal-organic framework (MOF) that adsorbs moisture from air, the unit requires appreciably less energy to adsorb and desorb moisture than conventional desiccants. The MOF coats a honeycomb substrate on a wheel that rotates between the outdoor air to be conditioned and the exhaust airstream rejecting heat from the building. As outdoor air passes, the MOF adsorbs the moisture, resulting in a drier air stream which is then cooled with a conventional vapor-compression cycle. This approach can meet both supply air dry bulb and dew point targets independently, allowing mechanical systems designers to optimize cooling loads in occupied spaces in a way that dew-point cooling technology cannot. To maximize efficiency, it uses heat rejected by the cooling process to regenerate (i.e., dry) the MOF so it can adsorb additional moisture. In shoulder and heating seasons, the ReD-DOAS operates like a conventional energy recovery wheel.

The ReD-DOAS system is expected to result in the following DoW benefits:

1. Reduced space cooling energy consumption (kWh) by at least 40%. 
2. A simple payback period of <4 years. 
3. Consistent supply air dew point temperature below 55°F, without reheat energy. 
4. Improved indoor environmental quality. 
5. Clear paths to adoption in DoW facilities

(Anticipated Project Completion - 2028)