Integral storage collector solar heating system
AssigneeArthur D. Little, Inc.
InventorW. Peter Teagan
Life of this patent
Estimating the term…
Abstract
In an integral storage collector solar heating system, water heated in a conventional hot water heater is first preheated in an integral storage collector. The storage collector includes a heat storing medium, preferably clean water, in a storage tank. Water to be heated is forced by line pressure through heat exchange pipes immersed in the heat storing water. The heat of fusion of the storing water prevents freezing of the line water. To preclude excessive pressure in the heat storage tank with high temperatures of the heat storing water, a heat pipe is provided to act as a large heat leak at about the vaporization temperature of the water. Also, a pressure relief valve is provided. The system avoids freezing and contamination of the water and does not require temperature control circuitry or a pump.
Claims33
A solar heating system for heating water comprising:
- an integral storage collector exposed to solar illumination, the storage collector including absorber means for absorbing solar energy, a heat storage medium of large heat capacity and high thermal conductivity directly heated by said absorber means, and a water flow path in heat exchange relationship with the heat storage medium;
- a water outlet from said water flow path connected as a pressurized, heated water supply;
- and
- a water inlet to said water flow path connected to a primary pressurized water supply line such that line pressure forces fresh water through the water flow path of the integral storage collector as heated water is taken from the water outlet.
A solar collector for heating water comprising:
- absorber means for absorbing solar energy;
- a heat storage medium directly heated by said absorber means, the storage medium having a fusion temperature which is about the same as and not less than the fusion temperature of water;
- a water flow path in heat exchange relationship with the heat storage medium;
- and
- thermal insulation insulating the side of the heat storage medium opposite the absorber means.
A solar collector for heating water comprising:
- absorber means for absorbing solar energy;
- a storage tank for holding a volume of heat storage liquid directly heated by the absorber means;
- and
- a water conduit through the storage tank;
- the freezing time ratio of V/U being at least about one gallon-hour-.degree.F./BTU, where V is the volume of the storage tank per absorber surface area in gallons/square foot and U is the collector heat transfer coefficient in BTU/ft.sup.2 -.degree.F.-hr.
A solar collector having a heat transfer liquid therein heated by absorbed solar energy and further comprising:
- a heat pipe extending from adjacent the heat transfer fluid into a relatively low temperature region to act as a large heat leak from the heat transfer fluid at about the temperature of vaporization of a heat pipe fluid.
A method of heating water comprising:
- providing a solar collector having a heat storage medium therein and a water conduit in heat exchange relationship with the heat storage medium;
- exposing the solar collector to solar illumination;
- and
- directing line water at line pressure through the water conduit of the solar collector.
A method of preventing freezing of water in a solar collector comprising providing a mass of water in the collector having a freezing time ratio of M/U of at least about 8 pound-hour-.degree.F./BTU where M is the weight of water in pounds per square foot of collector surface area and U is the heat transfer coefficient of the collector in BTU/ft.sup.2 -.degree.F.-hr.
A method of preventing freezing of water in a solar collector located where the water is subject to freezing comprising providing a mass of water in the collector having a freezing time ratio of M/U selected according to worst case regional climatic conditions to prevent freezing, where M is the weight of water per absorber surface area and U is the heat transfer coefficient of the collector.
Dependencies are inferred from the claim text.