Abstract: An evaporator for a micro combined heat and power system. The evaporator includes a heat source, an enclosure with a heating chamber and a primary fluid flowpath, and tubing that can carry a working fluid through a secondary fluid flowpath that intersects the primary fluid flowpath. The tubing is grouped into stages, including a first, or proximal, stage situated closest to the heat source, a second, or intermediate, stage downstream of the heat source relative to the proximal stage, and a third, or distal, stage downstream of the heat source relative to the proximal and intermediate stages. The stages of the evaporator tubing, while preferably circuited in a hybrid co-flow and counterflow arrangement, can also be used with purely co-flow or purely counterflow configuration. The proximal stage can be made from a first, relatively robust material, while the distal stage can be made from a second, relatively high thermal conductivity material.

Abstract: A multi-category gaseous fuel-fired heating apparatus having a combustion chamber, a mixing chamber in fluid communication with the combustion chamber, and an induced draft blower in fluid communication with the mixing chamber whereby combustion air is drawn into the combustion chamber for combustion of the gaseous fuel and the flue gases are drawn from the combustion chamber through the mixing chamber and exhausted into either a high temperature flue gas vent or a low temperature flue gas vent. The mixing chamber includes a dilution air inlet which, in a high temperature vent mode of operation of the heating apparatus is sealed off by an orifice plate disposed between the mixing chamber and the induced draft blower, and in a low temperature vent mode, the dilution air inlet is open and a larger blower inlet orifice is used.

Abstract: A method, apparatus and system is provided for controlling the rate of insolation transmission through the roof of a building, such as a greenhouse. The roof is provided with translucent panels through which liquid containing opaquing material passes. Control is effected by varying the amount of opaquing material passing through the panels, according to preselected optimum fulfillment of the combined heating, cooling and insolation needs of the building under varying atmospheric conditions.

Abstract: Passive environmental heating and cooling systems are described, which utilize heat pipes to transmit heat to or from a thermal reservoir. In a solar heating system, a heat pipe is utilized to carry heat from a solar heat absorber plate that receives sunlight, through a thermal insulation barrier, to a heat storage wall, with the outer end of the pipe which is in contact with the solar absorber being lower than the inner end. The inclining of the heat pipe assures that the portion of working fluid, such as Freon, which is in a liquid phase will fall by gravity to the outer end of the pipe, thereby assuring diode action that prevents the reverse transfer of heat from the reservoir to the outside on cool nights. In a cooling system, the outer end of the pipe which connects to a heat dissipator, is higher than the inner end that is coupled to a cold reservoir, to allow heat transfer only out of the reservoir to the heat dissipator, and not in the reverse direction.