Valerij Maisotsenko -- M-Cycle -- Indirect Evaporative Cooling -- Articles & Patents ![](0logo.gif) **[rexresearch.com](../index.htm)** --- **Valeriy MAISOTSENKO** **M-CYCLE** **( Indirect Evaporative Cooling )** --- ![](maisotsenko.jpg) **Dr. Valerij Maisotsenko** --- Atmospheric air is a clean renewable energy source, and it can be used for many applications, using the Maisotsenko Cycle or M-Cycle a revolutionary new breakthrough in thermodynamics. High degree of thermodynamic perfection of the M-Cycle allows atmospheric air to be cooled (without humidification) not the wet-bulb temperature, but the dew point temperature, and it increases psychrometric temperature difference and, consequently, energy resource of the atmospheric air. The M-Cycle has transitioned into the Coolerado Cooler from the conceptual stage to commercial applications which offers up to an 80% reduction of power for air conditioning of homes, commercial, and industrial buildings. The Coolerado Cooler has gained Federal recognition through the agencies of the Department of Energy at NREL and FEMP. Our coolers fall into a new category of an ?ultra? class cooler because of our extreme energy efficiency and ability to cool air below the wet bulb temperatures without compressor and CFC-ozone depletion. Today the M-Cycle assists Federal agencies reach their energy-use reduction goals and it has been successfully tested and researched for cooling applications by NREL (FEMP), Delphi, SMUD, PG&E, Sanwa, etc. Since then, this product received wide recognition from all over the world: Coolerado Cooler won the 2004 R&D 100 award, the US Green Builder 2006 Top Ten Product award, and just recently, the 2007 Sustainable Business Silver Medal of Honor award. --- **To: "Integrity Research Institute, Thomas Valone" ** **Date: Jun 26, 2007 2:39 PM** **Maisotsenko Cycle Recommended by NREL - Low power consumption** **Prof. Valeriy Maisotsenko** ( May 15, 2007 ) [**http://www.idalex.com**](http://www.idalex.com) [**http://www.coolerado.com**](http://www.coolerado.com) Renewable Energy is advance national energy goal to change the way we power our homes, businesses, and cars. The National Renewable Energy Laboratory (NREL) is the USA primary laboratory for renewable energy and it recommends utilizing the Maisotsenko Cycle for cooling applications. Atmospheric air is a clean renewable energy source, and it can be used for many applications, using the Maisotsenko Cycle or M-Cycle a revolutionary new breakthrough in thermodynamics (see our U.S. Patents No 6,497,10 7; 6,581,402; 6,705,096; 6,776,001; 6,779,351; 6,854,278; 6,948,558; 7,007,453; 7,197,887; 7,228,669; etc.). High degree of thermodynamic perfection of the M-Cycle allows atmospheric air to be cooled (without humidification) not the wet-bulb temperature, but the dew point temperature, and it increases psychrometric temperature difference and, consequently, energy resource of the atmospheric air. The M-Cycle has transitioned into the Coolerado Cooler from the conceptual stage to commercial applications which offers up to an 80% reduction of power for air conditioning of homes, commercial, and industrial buildings. The Coolerado Cooler has gained Federal recognition through the agencies of the Department of Energy at NREL and FEMP. Our coolers fall into a new category of an ?ultra? class cooler because of our extreme energy efficiency and ability to cool air below the wet bulb temperatures without compressor and CFC-ozone depletion. Today the M-Cycle assists Federal agencies reach their energy-use reduction goals and it has been successfully tested and researched for cooling applications by NREL (FEMP), Delphi, SMUD, PG&E, Sanwa, etc. Since then, this product received wide recognition from all over the world: Coolerado Cooler won the 2004 R&D 100 award, the US Green Builder 2006 Top Ten Product award, and just recently, the 2007 Sustainable Business Silver Medal of Honor award. However, this is only the first of many practical applications that the M-Cycle can be applied towards in reducing total energy consumption and pollution by increasing thermal transferal efficiencies (see attached 2). All of these power generation technologies can be improved through the M-Cycle. For instance, the M-Power Cycle enabled combustion engine will reduce environmental pollution from 75% to 95%, reduce fuel consumption by 25% to 40%, and have a minimum thermal efficiency of 55% (see attachment 3). Also, the M- Power Cycle should have many applications for increasing the efficiency of power systems because it utilizes the best heat recovery process for various forms of combustion engine. Today the M-Power Cycle promises better and cleaner generation technologies (see our U.S. Patents No 6,948,558 and 7,007,453). The M-Cycle is also the enabling technology around our prototype evaporative refrigerant condenser and is 60 percent more efficient than today's best condensers. The unique properties of the M-Cycle makes it the ideal candidate for advanced energy efficient vehicles and fuel cells, power plant systems and micro scale power plants, improve energy efficiency of buildings and solar, thermal, and wind energy based technologies. I believe it is a very logical step to extend the proven M-cycle heat and mass transfer technology towards environmentally-friendly and energy efficiency technologies. Please allow me a brief introduction of our companies. Idalex Inc. and Coolerado LLC are emerging technology firms. We have patented the M-cycle for many practical applications. The world leader in automotive thermal technology Delphi Corp. has since license the manufacturing right to produce the special heat and mass exchanger, which realizes the M-Cycle, and has just begun to mass-produce this product (Coolerado Cooler) for stationary building air conditioning, vehicular air conditioning, etc. I would like to meet with you and your colleagues in order to discuss the potential for a technology partnership in the pursuit of evolving breakthrough energy efficient products. I am convinced that the M-Cycle will provide with an opportunity for rapid development of new renewable energy technologies for cleaner environment and greater world. energy independence. [**http://www.idalex.com**](http://www.idalex.com) **Dr., Prof. Valeriy Maisotsenko** **Chief Scientist,** **Idalex Technologies Inc.** **4700 W. 60th Ave., #3** **Arvada, CO 80003,** **Phone: 303-375-0878** **Fax: 303-375-1693** --- [**http://www.energypulse.net/centers/author.cfm?at\_id=278 as**](http://www.energypulse.net/centers/author.cfm?at_id=278%20as) **Background** Dr. Valeriy Maisotsenko obtained a Graduate Engineering Degree (equivalent to a masters degree) from the Odessa Institute of Refrigeration Engineering in 1963; a candidate of science degree in technology (equivalent to a Ph.D.) from the Odessa Institute of Refrigeration Engineering in 1970; and a doctor of science degree in technology (equivalent to a U.S. post-doctorate degree) from the Moscow Civil Engineering Institute in 1988. Dr. Maisotsenko is the former director of the Thermal Physics Research Laboratory in Odessa, Ukraine. While in this capacity, he was recognized by the Communist government of the former Soviet Union as one of 11 top inventors in the USSR. This was the first time the Soviet Government ever publicly recognized any of its scientists. Dr. Maisotsenkos efforts rewarded him with more than 125 heat-transfer and thermodynamics patents. In 1992, Dr. Maisotsenko immigrated to the United States of America and became a U.S. citizen in 1999. Dr. Maisotsenko is a co-founder of Idalex Technologies in Arvada, Colorado. As Idalexs chief scientist, he has co-authored 12 patents for this research and development company. He also is the co-founder of Coolerado LLC, a company that is using the Maisotsenko Cooling Cycle to provide affordable cooling to the world. --- [**http://www.wapa.gov/es/pubs/esb/2005/june/jun057b.htm**](http://www.wapa.gov/es/pubs/esb/2005/june/jun057b.htm) **Energy Services Bulletin** **Thermodynamic Discovery Increases Energy Efficiency** In conventional indirect evaporative cooling, the working air stream passes through the wet channels of the heat exchanger only once. This cooler air draws the heat from the product stream passing through the dry channels. (Artwork by Idalex) Dr. Valeriy Maisotsenko, former director of the Thermal Physics Research Laboratory in Odessa, Ukraine, brought a new thermodynamic cycle with him when he came to the United States in 1992. *Humidity affects different air temperatures* To understand the Maisotsenko Cycle, or M-Cycle, it is first necessary to explain the thermodynamic concepts of dry bulb temperature, wet bulb temperature and dew point. The dry bulb temperature is the air temperature measured with a standard thermometer. A standard thermometer with a wet piece of cloth covering its bulb is used to measure wet bulb temperature. As air passes over the wet cloth, the water in the cloth evaporates, drawing heat out of the thermometer. The wet bulb temperature is therefore lower than the dry bulb temperature. Taken together, the dry and wet bulb temperatures are used to calculate the moisture or humidity in the air. The greater the difference between the two temperatures, the drier the air is. The dew point is the air temperature where moisture in the air begins to condense or change from a vapor to a liquid. For dew to collect on a surface like a glass of ice water or blade of grass, the surface temperature must be at or below the dew point temperature. The dew point temperature is always the coldest of the three temperatures. *Heat exchanger key to cycle* Theoretically, the wet bulb temperature is the lowest temperature any evaporative cooling system or cooling tower can achieve. However, the M-Cycle is able to use indirect evaporative cooling technology to cool well below the wet bulb temperature, almost to the dew point of the incoming air. In the Maisotsenko Cycle, both the product and working air are incrementally cooled by some of the working air that is fractioned off to absorb moisture and heat. Because the working stream gets colder as it progresses through the cycle, it is able to draw more heat out of the product stream. (Artwork by Idalex) This is accomplished with a wet- and dry-channel heat and mass exchanger that is geometrically very different from a conventional IDEC component. The uniquely designed plate-wetting and channel system splits the incoming air stream into product and working (exhaust) streams. The working stream is first pre-cooled in a dry channel, then split again into many streams and directed into wet channels. The wet channels cool and saturate the working air incrementally, with each stream benefiting from the cooling on the next increment. This cycle occurs multiple times in a short physical space within the exchanger, resulting in progressively colder temperatures. The product stream travels the entire length of the exchanger in dry channels. Heat from the product air transfers across a heat exchange plate and into the colder working air and water as it evaporates on the working, wet side of the plate. The heat and moisture are then rejected as exhaust. When it enters the space to be conditioned, the product air has been cooled below the wet bulb of the incoming air with no moisture added. *M-Cycle has many applications* This new thermodynamic cycle, once considered impossible by scientists, promises tremendous energy-efficiency gains in HVAC, water-cooling and power production. T he Maisotsenko Cycle is the foundation of the Coolerado cooler. In independent laboratory tests, a cooler cooled product air up to 22 percent below the wet bulb temperature, and to within 85 percent of the dew point temperature. Idalex, the company that patented the M-Cycle, is currently working on other applications for this thermodynamic breakthrough. A Maisotsenko combustion turbine is in the design phase and Idalex is testing the first prototype of a highly efficient refrigerant condenser using Maisotsenko technology. --- [**http://www.wapa.gov/es/pubs/esb/2005/june/jun057.htm**](http://www.wapa.gov/es/pubs/esb/2005/june/jun057.htm) **New Cooler Combines Comfort, Efficiency** A revolutionary new cooling technology that delivers the comfort of an air conditioner with the efficiency of an evaporative cooler is creating a big buzz among utilities and energy and facility managers. Coolerado, located in Arvada, Colo., puts a 21st century spin on evaporative cooling. R&D Magazines 100 Awards program hailed the system as one of the years most technologically significant products introduced to the world in 2004. Sacramento Municipal Utility District and the Colorado Governors Office of Energy Management and Conservation have partnered with the company on demonstrations. It cools as well as an air conditioner, and on a third the amount of electricity, said OEMC Senior Deputy Director Ed Lewis. It doesnt have a compressor, there are no greenhouse gas effects and unlike a swamp cooler, it doesnt release water into the air that enters the building. *Technology mimics air conditioning* Because the Coolerado cooler uses water to cool, people often mistakenly compare it to direct evaporative, or swamp coolers. The traditional, refrigerant-based air conditioner is a more apt comparison. The unit draws fresh outside air from the supply side. A heat and mass exchanger removes the heat from the product air similar to the way an air conditioner cools the air stream with refrigerant-filled cooling coils. Both the Coolerado Cooler and the conventional air conditioner reject heat into the atmosphere outside the building. The AC rejects heat as hot air, while the Coolerado unit rejects it as water vapor. Swamp coolers add moisture to the air and do not reject heat. Unlike conventional AC units, the Coolerado uses no ozone-depleting chemicals and has only one energy-consuming componentthe fan. Setting the Coolerado apart from traditional indirect evaporative coolers are a unique wetting system, a heat and mass exchanger made of unusual material and the way the air flows through the modular HMX. The heat and mass exchanger is what does most of the work, like the engine of the car, said company President Rick Gillan. The HMX is made of plastic-coated, cellulose blend fiber in a geometric design that cools both the product and working air streams. This cascading incremental airflow creates a new thermodynamic cycle called the Maisotsenko Cycle after Dr. Valeriy Maisotsenko who discovered it. Dr. Maisotsenko is a partner in Idalex Technologies, Coolerados parent company. *Consumer demonstrations show promise* Gillan estimates that more than half the worlds cooling applications could benefit from a Coolerado system. This product helps from both the power consumption and power production sides. Coolerados first commercial demonstration with the OEMC and Mount St. Vincent Home in northwest Denver illustrated the coolers consumer value. A project team installed a model C676 on the roof of the attic above the schools computer lab in 2003. The unit cooled the poorly insulated, century-old building to 74 degrees using 80 percent less power than an air conditioner. SMUD Project Manager Dave Bisbee met Idalex representatives at an evaporative cooling meeting where he was sharing his utilitys experiences with an indirect/direct system. The technology has been fraught with problems, he said. I told vendors that IDECs wont take off until the reliability improves. Gillan considered that a challenge and offered SMUD a Coolerado system to test. We decided to test the Coolerado at a school that has been experiencing chronic problems with their IDECs. They had nothing to lose, said Bisbee, and if it works, the school has the option of replacing all of its IDEC units with Coolerados. SMUDs Customer Advanced Technologies Program sponsored the replacement of an IDEC on a Sacramento school with the Coolerado in August 2004. The first thermal measurements were impressive, but the true test will be a full cooling season, said Bisbee. Were cautiously optimistic, he admitted. We would like to see a unit work reliably for three or four years." --- [**http://www.coolerado.com**](http://www.coolerado.com) **Coolerado LLC** **4700 West 60th Avenue, Unit 3** **Arvada, CO, USA 80003** **Phone: 303-375-0878** **Fax: 303-375-1693** Coolerado's Energy Efficiency Ratio (EER) of 40 has been independently verified, and is obtained by using a 21st century thermodynamic cycle. Other companies touting a SEER at 19.50\* as the highest efficiency air conditioners available use technology developed in the 1800s. Uses 80 Percent Less Power and No Chemical Refrigerants Atmospheric air is a clean renewable energy source, and it can be used for many applications, using the Maisotsenko Cycle or M-Cycle a revolutionary new breakthrough in thermodynamics (see our U.S. Patents No 6,497,10 7; 6,581,402; 6,705,096; 6,776,001; 6,779,351; 6,854,278; 6,948,558; 7,007,453; 7,197,887; 7,228,669; etc.). High degree of thermodynamic perfection of the M-Cycle allows atmospheric air to be cooled (without humidification) not the wet-bulb temperature, but the dew point temperature, and it increases psychrometric temperature difference and, consequently, energy resource of the atmospheric air. The M-Cycle has transitioned into the Coolerado Cooler from the conceptual stage to commercial applications which offers up to an 80% reduction of power for air conditioning of homes, commercial, and industrial buildings. The Coolerado Cooler has gained Federal recognition through the agencies of the Department of Energy at NREL and FEMP. Our coolers fall into a new category of an ?ultra? class cooler because of our extreme energy efficiency and ability to cool air below the wet bulb temperatures without compressor and CFC-ozone depletion. Today the M-Cycle assists Federal agencies reach their energy-use reduction goals and it has been successfully tested and researched for cooling applications by NREL (FEMP), Delphi, SMUD, PG&E, Sanwa, etc. Since then, this product received wide recognition from all over the world: Coolerado Cooler won the 2004 R&D 100 award, the US Green Builder 2006 Top Ten Product award, and just recently, the 2007 Sustainable Business Silver Medal of Honor award. --- [**http://www.idalex.com/technology/index.htm**](http://www.idalex.com/technology/index.htm) **A Technical Description of the Maisotsenko Cycle** **(Diagrams only)** ![](Flow-Figure-1.jpg) > > **Figure 1: Cross section sketch shows direct > > evaporative cooling.** ![](Psych-Chart-1a.jpg) **Figure 1a: Psychrometric chart of direct evaporative cooling.** ![](Flow-Figure-2.jpg) **Figure 2: Cross section sketch shows indirect evaporative cooling.** ![](Psych-Chart-2a.jpg) **Figure 2a: Psychrometric chart of indirect evaporative cooling.** ![](Diagram-of-Indirect-Evapora.jpg) **Figure 3: Diagram of indirect evaporative cooling.** ![](Flow-Figure-4.jpg) **Figure 4: Cross section sketch shows adiabatic heat and mass exchanger.** ![](Psych-Chart-4a.jpg) **Figure 4a: Psychrometric chart of adiabatic heat and mass exchanger.** ![](Flow-Figure-5.jpg) **Figure 5: Cross section sketch shows counter flow heat and mass exchanger** ![](Psych-Chart-5a.jpg) **Figure 5a: Psychrometric chart of counter flow heat and mass exchanger.** ![](Flow-Figure-6.jpg) **Figure 6** ![](V-Channel-opened-up.jpg) > > **Figure 7: Diagram of actual perforated cross flow > > heat and mass exchanger with air flow paths**. --- **US Patent # 6,497,107** **Method and Apparatus of Indirect-Evaporation Cooling** **Dec. 24, 2002** **Valeriy Maisotsenko, et al.** **Abstract** The within invention improves on the indirect evaporative cooling method and apparatus by making use of a working fluid that is pre-cooled with and without desiccants before it is passed through a Wet Channel where evaporative fluid is on the walls to take heat and store it in the working fluid as increased latent heat. The heat transfer across the membrane between the Dry Channel and the Wet Channel may have dry, solid desiccant or liquid desiccant and may have perforations, pores or capillary pathways. The evaporative fluid may be water, fuel, or any substance that has the capacity to take heat as latent heat. The Wet Channel or excess cooled fluid is in heat transfer contact with a Product Channel where Product Fluid is cooled without adding any humidity. An alternative embodiment for heat transfer between adjacent channels is with heat pipes. --- **US Patent # 6,581,402** **Method and Plate Apparatus for Dew Point Evaporative Cooler** **V. Maisotsenko, et al.** **Abstract** An improved method and apparatus for indirect evaporative cooling of a fluid stream to substantially its dew point temperature. Plate heat exchanger has perforations 11 and channels 3, 4 and 5 for gas or a low temperature for liquids on a dry side and wet side. Fluid streams 1 flow across the dry side 9, transferring heat to the plate. Gas stream 2 flows across the dry side and through perforations to channels 5 on wet side 10, which it then cools by evaporative cooling as well as conductive and radiative transfer of heat from plate. A wicking material provides wetting of wet side. In other embodiments, a desiccant wheel may be used to dehumidify the gas, air streams may be recirculated, feeder wicks 13 and a pump may be used to bring water from a water reservoir, and fans may be used to either force or induce a draft. The wicking material may be cellulose, organic fibers, organic based fibers, polyester, polypropylene, carbon-based fibers, silicon based fibers, fiberglass, or combinations of them. The device may be operated in winter months to scavenge heat from exhaust gases of a space and thus pre-heat fresh air, while simultaneously humidifying the fresh air. --- **US Patent # 6,705,096** **Method and Plate Apparatus for Dew Point Evaporative Cooler Using a Trough Wetting System** **V. Maisotsenko, et al.** **Abstract** An improved method and apparatus for indirect evaporative cooling of a fluid stream to substantially its dew point temperature. Plate heat exchanger has perforations (11) and channels (3, 4 and 5) for gas on a dry side and wet side. There is a trough formed in a portion of the plate that temporarily holds evaporative fluid which is in contact with the wick material on the wet side surface of the plate. The evaporative fluid flows through the trough by way of liquid perforations into the next trough. The trough of a plate with a wet side up, the liquid perforations are on the side creating a reservoir to wet the opposing wick materials. As streams flow across the dry side (9), transferring heat to the plate. Working gas stream (2) flows across the dry side and through perforations to channels (5) on wet side (10), which it then cools by evaporative cooling as well as conductive and radiative transfer of heat from plate. --- **US Patent # 6,776,001** **Method and Apparatus for Dew Point Evaporative Product Cooling** **V. Maisotsenko, et al.** **August 17,2004** **Abstract** The present invention relates to a method and an apparatus for providing enhanced indirect evaporative cooling of air, water, fuel, or other fluids while controlling the humidity. The design makes cooling down to the dew point possible without energy input other than the energy to produce the fluid flow needed. The design makes use of stacked composite plates (7) with channels (1, 2) for fluid flow between adjacent plates. On opposing surface areas of these plates, there are wet areas (4) or dry areas (3). The wet areas (4) provide cooling by conventional evaporation which is in turn used to cool the fluids in contact with the dry areas (3). The benefit is controlled heat transfer, which allows selected cooling of fluid flow such that the temperature as low as dew point are reachable. --- **US Patent # 6,779,351** **Fuel Cell Systems with Evaporative Cooling and Methods for Humidifying and Adjusting the Temperature of the Reactant Streams** **V. Maisotsenko, et al.** **Abstract** A fuel cell using fuel and oxidant resulting in the production of water and heat in addition to electrical power. The fuel cell employs an evaporative cooler and has methods to adjust the moisture and temperature for the fuel and oxidant flows to improve the fuel cell efficiency. The water produced by the fuel cell is used to provide the water for wet channels of the evaporative cooler. The evaporative cooler has separate product channels and dry working channels that are cooled by heat transfer across a heat exchanger plate. The heat exchanger plate forms part of each wet working channel on the wet side of the heat exchanger plate and part of the product channel and the dry working channel on the dry side. The fuel passes first through the dry working channel then the wet working channel becoming humidified by the evaporation therein and cooling the heat exchanger plate before going to the anode of the fuel cell. The oxidant is cooled by passing through the product channel before being directed to the cathode. In another embodiment, the evaporative cooler is incorporated with the fuel cell and is formed by an anode separator, with the fuel flowing by a dry side of the heat exchanger plate of the anode separator that is being cooled by the evaporation on the wet side. The evaporation adding moisture to the fuel as it passes by the wet side and the heat exchanger plate cooling the fuel on the dry side. --- **US Patent # 6,854,278** **Method of Evaporative Cooling of a Fluid and Apparatus Therefor** **V. Maisotsenko, et al.** **15 Feb. 2005** **Abstract** The operating efficiency of indirect evaporative cooling processes and indirect evaporative cooling apparatus employing a dry side channel and a wet side channel separated by a heat exchange plate are improved by placement of holes in the heat exchange plate. Further improvements are obtained when the flow direction in the wet side channel is cross-current to the flow direction in the dry side channel. Placement of desiccant materials in the dry side channel also serve to improve the operating efficiencies of these processes and apparatus. --- **US Patent # 6,948,558** **Evaporative Duplex Counterheat Exchanger** **27 Sept. 2005** **V. Maisotsenko, et al.** **Abstract** A duplex exchanger includes first and second heat exchangers each including a main flow channel and a cooperating counterheat channel. The first counterheat channel is joined to the first main flow channel for receiving a cooled primary stream therefrom. The second counterheat channel is also joined to the first main channel splitting the primary stream therefrom. An evaporative coolant is injected into the first counterheat channel, and an evaporative saturant is injected into the second counterheat channel. Heat from the initially hot primary stream in the first exchanger evaporates the coolant in the first counterheat channel for self-cooling the primary stream in the first main channel. Heat from a hot secondary stream channeled through the second main channel evaporates the saturant in the second counterheat channel for adding mass to the primary stream channeled therethrough. --- **US Patent # 7,007,453** **Power System and Method** **7 March 2006** **V. Maisotsenko, et al.** **Abstract** A power system includes a device for extracting energy from a hot gas stream to power a driveshaft. An evaporative duplex counterheat exchanger is disposed in flow communication with the energy extracting device. The duplex exchanger includes a first heat exchanger having a first main flow channel, and a counterheat channel joined in flow communication therewith. A second heat exchanger includes a second main flow channel adjacent the counterheat channel. And, an evaporative fluid is injected into the counterheat channel to evaporatively cool the flow through both main flow channels. --- **US Patent # 7,197,887** **Method and Plate Apparatus for Dew Point Evaporative Cooler** **3 April, 2007** **V. Maisotsenko, et al.** **Abstract** An improved method and apparatus for indirect evaporative cooling of a fluid stream to substantially its dew point temperature. Plate heat exchanger has perforations 11 and channels 3, 4 and 5 for gas or a low temperature for liquids on a dry side and wet side. Fluid streams 1 flow across the dry side 9, transferring heat to the plate. Gas stream 2 flows across the dry side and through perforations to channels 5 on wet side 10, which it then cools by evaporative cooling as well as conductive and radiative transfer of heat from plate. A wicking material provides wetting of wet side. In other embodiments, a desiccant wheel may be used to dehumidify the gas, air streams may be recirculated, feeder wicks 13 and a pump may be used to bring water from a water reservoir, and fans may be used to either force or induce a draft. The wicking material may be cellulose, organic fibers, organic based fibers, polyester, polypropylene, carbon-based fibers, silicon based fibers, fiberglass, or combinations of them. The device may be operated in winter months to scavenge heat from exhaust gases of a space and thus pre-heat fresh air, while simultaneously humidifying the fresh air. ---