This invention is related to the field of grid independent energy systems. Specifically, this is related to heating systems that do not require electricity or hydrocarbon provided by the grid to warm houses or buildings in isolated and remote areas. Even more, this invention relates to systems that can be manufactured at relatively low costs and can be assembled on site. Since one embodiments of the system can use rocks inside a container to store the collected thermal energy, it makes easy to make without sophisticated manufacturing processes. There are several expressions of previous art, but none of them have the key innovative characteristics of this one, all in one system: namely:
A Trombe wall is a massive Equator-facing wall that is painted a dark color in order to absorb thermal energy from incident sunlight and covered with a glass on the outside with an insulating air-gap between the wall and the glaze. http://hiddenarchitecture.net/ungreen-trombe-wall/Some of the differences between US20050061312A1″Wall integrated thermal solar collector with heat storage capacity” and this patent are that the US20050061312A1: 1) is not modular and does not allow to dimension the collector and accumulator depending on the geographical position where the house or building is; 2) does not allow to accumulate thermal energy for more than one night of use or for variability of the solar radiation during the days; and 3) is not easy to dimension and manufacture, and assembled on site by mostly unskilled people. The Solar energy collector and thermal storage device WO2011044014A1 has the same limitations as US20050061312A1, and in addition: 1) it cannot store enough thermal energy to warm a house for more than a few hours; and 2) it does not allow to orient the collector in the optimum direction with respect the north-south line and it cannot be inclined with respect to the horizontal plane to maximize the transformation to solar radiation into thermal energy. The Trombe wall has all the limitations of the first two just analyzed above.
This invention distinguishes from other inventions and from what is old in that it is modular; can be dimensioned to provide with enough thermal energy for more than one day to warm a house or building that is not connected to the grid; can be assembled on site; can be manufactured with mostly inexpensive materials, which makes it a good solution for mostly deprived or isolated areas; its collector can be easily and optimally oriented with respect to the north-south line and with respect to the horizontal plane to maximize exposure to solar radiation and thermal energy generation.
This patent (1) discloses a system and a method to maintain the temperature inside a building or house within comfort levels independently of the Grid. The system has three main components: a collector (C), an accumulator (A), and transformer (T). The method consists on transforming energy from solar radiation through a collector (C) into thermal energy, accumulating that energy into an accumulator (A), and transforming that accumulated energy into thermal energy to later warm the internal environment of buildings. One embodiment of the system has two loops. The first of those two loops functions between dawn and sunset and includes only the collector (C) and the accumulator (A). The second loop includes only the accumulator (A) and the transformer (T) and operates primarily between sunset and dawn. The first embodiment has only one of the two loops working at a time. In the first loop, its collector (C) uses a blackened surface that transforms the energy coming from the sun in the form of radiation into thermal energy that increases the temperature of air that is in contact with the blackened surface. The air whose temperature has been increased in the collector is moved to an accumulator (A). One embodiment of the accumulator (A) uses rocks in which the heat is conserved during the day; however, this does not exclude other materials to be used to store the thermal energy inside the accumulator (A). When the accumulated thermal energy is needed to warm up the interior of a building, which we refer to as the transformer (T), the second loop is activated between the accumulator and the building into which the energy is transferred to increase its internal temperature with respect to the surrounding ambient.
This invention brings several unique innovative characteristics that are not found integrated in an integrated system in previous art; namely, the system of this invention can operate independently of the grid. Besides, the system and method of this invention can help to deliver clean energy to historically overburdened and underserved communities worldwide. Additionally, the system of this invention is modular, and each of its three main modules, the collector (C), the accumulator (A), and the transformer (T) can be dimensioned and built separately and integrated in the full system to perform depending on the requirements determined by the user. Besides, the modules and therefore the system can be built with relatively inexpensive material. The system of this invention can be utilized in extremely cold and isolated areas where there is not access to the Grid; does not rely on solar panels (SP) to generate the thermal energy; and its modules or the entire system can be constructed and assembled on site.
In its main embodiment, the collector (C) is a box with three parallel surfaces. The top an outer most surface and the one next to it have a gap between them. The top and outer most surface is made of a transparent material that allows for the sunlight and radiation to cross it. The middle surface is black in color on the side that faces the top and outer most surface. The gap between both surfaces uses the greenhouse effect to transform the solar energy that arrives as radiation into thermal energy that warms the black surface. Behind the middle surface, between it and the third and last surface, there is air, which is warmed as it gets in contact with the back side of the back surface. (Rectangular funnel) The air behind the blackened surface increases its temperature. There is a loop that connects the collector and the accumulator (A). In its main embodiment, this loop connects the collector (C) with the accumulator (A) by means of conduits through which the air flows from the collector (C), traverses the material inside the accumulator from top to bottom, which in its main embodiment is rocks; runs back from the bottom of the accumulator (A) into the collector (C); and after the air circulates through the collector (C), it is sent back to the Accumulator (A). This loop is kept running between dawn and sunset. This process warms the material inside the accumulator (A), increases its average temperature above the ambient temperature, allows to accumulate the thermal energy collected by the collector inside the accumulator (A), so it can be used to warm the building—the transformer (T) when needed. The system has valves (V) that allow to turn on or off the loops as needed. This allows the collection and accumulation of energy, between the collector (C) and the accumulator (A); and the warming of the building interior when passing the accumulated energy from the collector (C) to the transformer (T) when needed.
The best performance is achieved when the collector (C) is placed in a specific alignment, when its longitudinal axis is aligned along the North-South orientation, and an it has an inclination with respect to the horizontal plane as a function of the Longitude and Latitude coordinates of the place where the building to be warmed is. The collector (C) can be placed in almost any place near the building including on top of its roof; however, it is recommended to avoid as much as possible a position that occludes the sunlight due to shades produced by buildings or other elements between dawn and sunset. The accumulator (A) can be placed in any place outside and near the building that it will warm; however, it can also be placed inside the building. Whatever relative position between Collector (C), Accumulator (A) and Transformer (T), it is recommended to minimize the length of tubing that connects them so as to minimize energy loses due to the exposure of the tubing to differential temperature across its walls. This system is modular, which allows a variety of combinations to handle different heating energy demands for different environment temperatures and climates. Besides, the system can be made with relatively inexpensive materials, which allows it to be used in relatively deprived areas in the world as well as isolated areas at high altitudes where other sources of energy are not available such as electric or hydrocarbons-based energy. Its modularity allows it to be sized to address energy heating demands of distinct types and sizes of buildings.