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Liquid Desiccant Air Conditioning and Dehumidification (LDAC) has been emerging in the past 10 to 15 years as an energy-saving alternative design for applications that require high moisture removal and a Cleantech solution that has the potential to provide significant energy savings when applied to more broad markets. Buildings are the primary users of electricity in the U.S., consuming about 75% of the total electricity produced and about 40% of all U.S. primary energy use and associated greenhouse gas (GHG) emissions. A substantial portion of that energy is used for air conditioning and dehumidification. Furthermore, the U.S. Department of Energy (DOE) reports that U.S. buildings account for 35% of the U.S. carbon dioxide emissions that drive the climate crisis. One specific application that requires significant moisture removal is the indoor cultivation of legal cannabis. It is estimated by the DOE that by the end of this decade, electrical energy usage by indoor cannabis operations will be on par with the electrical energy consumed by either data centers or for the recharging of electrical vehicles. More recent projections indicate cannabis sales are expected to double from 2021 to 2030. As such, more efficient and economical methods of climate control are necessary for more widespread application in cannabis operations to reduce the energy requirements. The added emphasis should be on methods to first reduce the energy required before building the electrical generating infrastructure to support such growing industries. Climate control of indoor cannabis cultivation is one such aspect where energy-efficient air conditioning and dehumidification can contribute to reducing the projected energy usage by end of this decade. This paper gives an overview of a standalone LDAC system and a hybrid LDAC combined with an air handling unit. This paper will present indoor grow room case studies from a side-by-side installation of a hybrid LDAC unit and Desiccant Wheel (DW) air handling system in two identical cannabis grow rooms. Integration with a Combined Heat and Power (CHP or cogeneration) plant onsite supplying energy for both the technologies will be examined. Further, comparative energy analyses of LDAC, DW technology, and other widely used technologies in the HVAC indoor growing environment will be discussed. This will be the first comprehensive, side-by-side performance and energy analysis of competing desiccant (LDAC and DW) technologies in a controlled, indoor agriculture environment. [ABSTRACT FROM AUTHOR]

The climate crisis currently being faced by humanity is going to increase extreme weather events which are likely to make long-duration power outages for communities increase in frequency and duration. Microgrids are an important part of electrical resilience for connected communities during power outages. They also can have transactive potential to save energy on electric loads through coordinating distributed energy resources. Microgrids are expensive though. Making electric load coverage available nearly 100% of the time given known design basis threats and component failure statistics is one of the largest drivers of cost. Such high availability is non-negotiable for critical applications such as life saving equipment in a hospital but could perhaps be compromised for less critical loads. This paper documents an analysis that used the Microgrid Design Toolkit and EnergyPlus simulation results with two energy retrofit options exercised. The results show how increasing energy efficiency and reducing availability to 90% and 80% reduced the calculated price of a photovoltaic and battery storage microgrid in a New Mexico neighborhood by 63% and 70%, respectively. A microgrid with 80% availability with 48-hour islanded run-time capability is therefore suggested as a low-cost method for accelerating microgrid infrastructure penetration into the residential sector. Such an "underbuilt" microgrid will significantly increase resilience even though it will not guarantee energy security for the non-critical applications in residential households. This will in turn accelerate the growth of storage potential across communities providing greater grid flexibility. The results of the study also show how increased insulation applied to the proposed residential community can be less expensive than creating a larger microgrid that carries larger electric loads. The likelihood that energy retrofits are a better investment than a larger microgrid is inversely proportional to availability. Here, availability is a metric equal to the percentage of the demand load served by the microgrid during power outages, not including the startup period. [ABSTRACT FROM AUTHOR]