Abstract:
A solar hot air system is provided containing a solar hot air collector and an inlet duct connected to the solar hot air collector and a building fresh air intake. A sensor is connected to the building fresh air intake, configured to measure fan speed and damper position. In addition, a sensor is connected to the inlet duct, configured to measure air volume and temperature. Further, a sensor is connected to the solar hot air collector, configured to measure internal and ambient temperature. A means for calculating a periodic fee to a user based at least in part upon an amount of generated energy is also provided.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to copending U.S. Provisional Application entitled, “SOLAR AIR THERMAL ENERGY SYSTEM AND ENERGY PURCHASE AGREEMENT METHOD,” having Ser. No. 61/487,559, filed May 18, 2011, Which is entirely incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to solar energy and more particularly, is related to providing energy services. 
       BACKGROUND OF THE INVENTION 
       [0003]    The price of using fossil fuels and/or electricity to heat buildings has been increasing, is expected to increase and has negative environmental consequences. Many people are looking for alternatives to provide stable and lower costs for heating their facilities. 
         [0004]    A building&#39;s heating load can be offset using solar heat in passive and active technologies. Passive solar involves design elements allowing solar thermal energy to lower a structure&#39;s heat loads. Other technologies, such as geothermal provide additional methods for stabilized thermal needs but rely on electricity to drive the system and complicated retrofit construction. Active solar, through hot water collectors and hot air collectors can also lower heat loads, but all of these options are often not selected due to their higher upfront costs. 
         [0005]    In the field of solar hot water systems, one solution that has been tried is a business method for providing a utility and calculating a rate to charge the customer that is not based on energy usage. However, such a method only discusses solar hot water, and specifically that the rate charged is not based on the amount of energy used. 
         [0006]    Another example in the solar field involves photovoltaic solar power, not solar heated air. This example involves the creation of financial instruments to purchase, lease, and maintain consumer premises equipment, and provides for shutting off the power if the consumer stops paying. This method does not provide for the proper financial structure to create a third-party ownership method or a fee based on energy production or displaced through heating systems. 
         [0007]    Another example in the geothermal field involves a fee that is based on a base fee which results from the system installation cost and a periodic fee that is based on the geothermal energy used. This example is limited to geothermal energy and has a fee that is based primarily on the cost of the system and less so on energy used, and not based on the value of the energy displaced. 
         [0008]    None of these examples apply directly to solar heated air and none provide a mechanism to understand the value of the energy produced or the energy displaced as a factor in recognizing the cost of the system. What is needed, therefore, are systems and methods for overcoming the shortcomings described above. 
       SUMMARY OF THE INVENTION 
       [0009]    Embodiments of the present invention provide a solar air thermal energy system and energy purchase agreement method. Briefly described, in architecture, one embodiment of the system, among others, can be implemented as follows. A solar hot air system is provided containing a solar hot air collector and an inlet duct connected to the solar hot air collector and a building fresh air intake. A sensor is connected to the building fresh air intake, configured to measure fan speed and damper position. In addition, a sensor is connected to the inlet duct, configured to measure air volume and temperature. Further, a sensor is connected to the solar hot air collector, configured to measure internal and ambient temperature. A means fir calculating a periodic fee to a user based at least in part upon an amount of generated energy is also provided. 
         [0010]    Other systems, methods, features, and advantages of the present invention will be or become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a schematic diagram of a first embodiment of a system according to the present invention. 
           [0012]      FIG. 2  is a schematic diagram of a second embodiment of a system according to the present invention. 
           [0013]      FIG. 3  is a process flow chart showing a method under a third embodiment of the present invention. 
           [0014]      FIG. 4  is a diagram showing details of one of the steps of the third embodiment. 
           [0015]      FIG. 5  is a schematic diagram illustrating an example of a system for executing functionality of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    Reference will be made in detail to embodiments of a system and method that satisfies the need for financing the system cost and the installation of a solar hot air system and charging a periodic fee based on the energy output of the system or the energy displaced by the system from the existing building system. A first exemplary embodiment of a system according to the present invention includes perforated solar hot air collector panels, spacing dips, extruded vertical bars, duct work to connect to a ventilation system, decorative capping, sensors to determine air flow and temperature, calculating means for determining a periodic fee amount of energy produced, and means for turning off the system in the event fees are not paid. A method according a third embodiment of the present invention may include the steps of designing and installing a solar hot air system to a customer&#39;s building, calculating a periodic fee to be charged to the customer, measuring solar hot air system production, and charging the customer for the energy produced or displaced. 
         [0017]      FIG. 1  is a schematic diagram of a first embodiment of a solar hot air system  100  including a thermal collector  102  that allows air to enter the system  100  either at the collector surface via perforations, at the top, side or bottom of the collector cavity via appropriately sized intake vents, or from the interior of the space when recirculation of air through the solar hot air system is used. The thermal collector  102  captures solar energy by heating the air within the collector  102 , thereby transferring solar energy to the heated air. The air leaves the thermal collector  102  via a conduit, for example, a duct, grill, or wall penetration  103  connected to the thermal collector  102  and travels to a facility using the heated air, for example, a building. The heated air may enter the building, for example into an existing or fitted air intake system  104 . Such an air intake system  104  may already be present or may be added to the building to meet the fresh air demands of the building. As shown in  FIG. 1 , the heated air may be delivered into the building, for example, through an existing ventilation system  105  impelled via a fan  106 . 
         [0018]    The system  100  may have a motorized first damper  112  that may allow the thermal collector  102  to be bypassed, for example, when a temperature set point is exceeded thereby allowing the ventilation system  105  to draw regular air into the mechanical unit as conventionally designed without the solar system. The system  100  may also include a second damper  107  to bypass the building and provide heated air to a storage media  108  for usage on site for heating or other purposes or for use at a later time. Examples of the storage media  108  may include, but are not limited to pressurized or atmospheric storage vessels with water or other storage medium, ground storage for geothermal or other thermal storage systems such as masonry, brick, rock, water, or other effective forms of thermal mass. Examples of the exchange media may include, but are not limited to, copper tubing for direct or indirect hot water generation, air to water heat exchangers for hot water generation, air to water heat pumps for building heating or heat generation, and air to air heat pumps for building heating or heat generation. 
         [0019]    The thermal collector  102  may be a perforated cladding system, non-perforated cladding system, glazed cladding system, or any effective cladding system with a cavity and/or substrate behind it which is designed to maximize solar energy generation. The cladding itself may he constructed of metal, plastic, polycarbonate, glazing (single or double layered) or any material shown to provide effective thermal conduction or effective transfer of solar energy to the location where energy is drawn. 
         [0020]    The thermal collector  102  may be designed or provided in a variety of colors which may impact performance. Energy from the thermal collector may be generated in a number of different, or a combination of different methods which may include but are not limited to heat which develops on the surface of a cladding material, heat which develops on the back side of the cladding system and is then scrubbed from the back of the cladding via air movement, heat which is scrubbed from the back of a heated cladding surface and is directed through the solar hot air system to allow further temperature increases, transfer of energy to the interior air cavity via a clear cladding material designed to allow solar energy to heat a conductive surface behind the cavity, and heat which develops via a heated thermal mass at the back face of the solar hot air system. 
         [0021]    In the same or another embodiment, monitoring equipment  122  may be installed to measure the production and usage of the system  100  at the location where energy is delivered to the conventional space or heating system  102 . Examples of such monitoring devices may include, but are not limited to, commercially available pre-configured monitors, such as by FatSpaniel Inc., Onset Computer or any client computer monitoring network such as energy management systems or a dedicated system management application. All metering and sensor equipment may be compatible with site specific controls or conditions from project to project. Data loggers may be used to obtain trending information for remote interpretation or energy calculations such as Hobo U30 Data Loggers or similar. 
         [0022]    In the same or another embodiment, a sensor may be connected to the system  100  in one or more locations, for example, a duct sensor  123 , a damper sensor  124 , and an intake fan sensor  125 . Each sensor  123 - 125  may be configured to collect temperature measurements to measure and monitor the amount and temperature of pre-heated air that is delivered to the building and the amount of thermal energy delivered to the building. Such measurements may be used to form the basis for a calculation of the amount of thermal energy generated and/or displaced by the system. 
         [0023]    In the same or yet another embodiment, one or more additional controls may be attached to the system so that existing controls of the system  100  may be overridden to deliver thermal energy into a building, or through a bypass  107  into a storage medium  108  for use at a scheduled time to take advantage of available thermal energy at a later time. 
         [0024]    Furthermore, a means for turning off the system  100 , for example, if fees are not paid, may also be connected to the system  100 . The means for turning off the system  100  may be, for example, a control unit connected to the damper  112 . Another example of a means for turning off the system  100  may be a computer command issued to this device from a computer. 
         [0025]      FIG. 2  is a schematic diagram of a second embodiment of a system  200  according to the present invention. Referring to  FIG. 2 , the heated air from a solar thermal collector  102  may be directly piped into a building space  212  through a duct  203  and driven by a fan  204  into the space  212  through a distribution duct  213 . Such direct piping may displace the need for a fresh air system connected to the space  212  to provide lower temperature fresh air. The controls in  FIG. 2  may be connected to temperature monitoring devices and control units that may communicate with existing control technologies of the building to optimize the use of pre-heated air over conditioned air from the heating system of the building. 
         [0026]    In the same or another embodiment, commercially available pre-configured monitoring equipment may be installed to measure the production of the system  200  and usage at the collector  222 . 
         [0027]    In the same or another embodiment, one or more sensors may be connected at one or more locations within the system  200 , for example, a duct sensor  223  may be attached to the duct  203 , or an intake fan sensor  224  may be positioned near the fan  204 . Such sensors may collect, for example, temperature measurements to measure and monitor the amount of preheated air and the temperature of pre-heated air that is delivered to the building, and thereby, the amount of thermal energy delivered to the building, forming the basis for a calculation of the amount of thermal energy generated by the system and/or displaced. 
         [0028]    The system  200  may include a switch  205  that deactivates the fan  224  to insure the thermal collector  202  is not providing heated air to the space when a temperature set point is exceeded, thereby allowing fresh air into the building that is not preheated. 
         [0029]    A calculating means for calculating a periodic usage fee to a user based on the usage of the system  200  may also be provided. The calculating means may be a computer storage device or media electronically connected to one of the sensors  223 ,  224 , the computer storage media may be connected, for example, to the internet to permit remote calculation of the period fee, monitoring of the system&#39;s operation and other data. Other examples of access to the computer storage media may include, but is not limited to, access via a serial or parallel port, for instance, with a thumb drive, wireless access, such as Bluetooth or WiFi, or removable media, such as a portable hard drive. 
         [0030]    Referring to  FIG. 1 , a means for bypassing the system  100 , through override of the motorized damper  112  in the event fees are not paid, may also be connected to the system  100 . In  FIG. 2  a means employed for bypassing the system  200  may be a switch connected to the fan  204 . The means for bypassing the system  200  may include converting the fresh air system to the prior configuration where unconditioned lower-temperature air is delivered to the building through the pre-existing heating system. The means for bypassing the system could be, for example, at least one electric switch. The means for bypassing the system  200  could be a computer command issued to the controller for the damper. 
         [0031]    A third embodiment of the present disclosure is a method for providing the services of solar pre-heated air systems such as the first embodiment shown in  FIG. 1  and the second embodiment of  FIG. 2 . At least a portion of the method under the third embodiment may be executed, for example, by a computer. Under the method of the third embodiment, for example, customers may avoid the upfront cost of purchasing and installing a solar hot air system, while a vendor may generate a profit by, for example, installing a solar hot air pre-heating system, and metering usage of the solar hot air pre-heating system that would be the basis of billing. Turning to  FIG. 3 , a vendor may evaluate, design, and install a solar hot air system for heating fresh air to be delivered into a building (block  302 ). The designer may estimate energy the solar hot air system will produce for the building (block  304 ) and calculate a periodic fee (block  306 ). The vendor and customer may enter into a term contract before the vendor can complete installation and metering and delivery begins. In situations that do not allow accurate metering of energy production, actual energy savings can be compared with projections to confirm an agreed upon rate and agreed margin of error. 
         [0032]    The vendor may develop a periodic fee (block  306 ) reflecting the cost for energy produced by the system and the predicted amount of energy that will be produced (block  304 ) or the amount of energy produced by the system as actually measured (block  308 ) as credited against the estimated fee, although this fee will include additional charges for monitoring and measuring. 
         [0033]      FIG. 4  is a detail of elements that may contribute to a base fee  420  used to calculate the periodic fee of block  306  ( FIG. 3 ). The elements of the base fee  420  may include a cost of designing and installing the system  402 , an equipment cost  404 , a rate of return  406 , predicted energy production of the system  410 , and estimated service maintenance costs  412 . The rate of return  406  may includes the financing costs. The predicted energy production  410  may affect the length of the contract. 
         [0034]    The periodic fee may be based on payments as negotiated based on the method for calculating the periodic fee. The periodic fee may be calculated using a base fee  420 . This can be created, for example, at a time agreed upon between the client and vendor and may represent a total fee necessary to secure financing, form the basis for tax-based incentives, and generate profit for the vendor. 
         [0035]    While the system is in use, there may be sensors and meters that measure the energy produced  308 , delivered, and/or displaced while combining where available the savings provided to the client. This may include savings related to recaptured heat losses from the building, de-stratification savings in certain circumstances and displaced/combustion efficiency savings compared with fossil fuels. 
         [0036]    Finally, there may be a means of turning off the delivery of pre-heated air to the building heating system via the energy metering mechanism, for example, the damper sensor  124  ( FIG. 1 ). The delivery of pre-heated air may be turned off, for example, by opening a dampener  112  ( FIG. 1 ), or with similar equipment to by-pass the delivery of the heated air into the air delivery unit to the building. This may indicate to the metering mechanism that there is no air being drawn into the building from the solar hot air system, and therefore no energy being delivered that may be billed. 
         [0037]    As previously mentioned, at least a portion of the present system for executing the functionality of the third embodiment described in detail above may be a computer, an example of which is shown in the schematic. diagram of  FIG. 5 . The system  500  contains a processor  502 , a storage device  504 , a memory  506  having software  508  stored therein that defines the abovementioned functionality, input and output (I/O) devices  510  (or peripherals), and a local bus, or local interface  512  allowing for communication within the system  500 . The local interface  512  can be, for example but not limited to, one or more buses or other wired or wireless connections, as is known in the art. The local interface  512  may have additional elements, which are omitted for simplicity, such as controllers, buffers (caches), drivers, repeaters, and receivers, to enable communications. Further, the local interface  512  may include address, control, and/or data connections to enable appropriate communications among the aforementioned components. 
         [0038]    The processor  502  is a hardware device for executing software, particularly that stored in the memory  506 . The processor  502  can be any custom made or commercially available single core or multi-core processor, a central processing unit (CPU), an auxiliary processor among several processors associated with the present system  500 , a semiconductor based microprocessor (in the form of a microchip or chip set), a macroprocessor, or generally any device for executing software instructions. 
         [0039]    The memory  506  can include any one or combination of volatile memory elements (e.g., random access memory (RAM, such as DRAM, SRAM, SDRAM, etc.)) and nonvolatile memory elements (e.g., ROM, hard drive, tape, CDROM, etc.). Moreover, the memory  506  may incorporate electronic, magnetic, optical, and/or other types of storage media. Note that the memory  506  can have a distributed architecture, where various components are situated remotely from one another, but can be accessed by the processor  502 . 
         [0040]    The software  508  defines functionality performed by the system  500 , in accordance with the present invention. The software  508  in the memory  506  may include one or more separate programs, each of which contains an ordered listing of executable instructions for implementing logical functions of the system  500 , as described below. The memory  506  may contain an operating system (O/S)  520 . The operating system essentially controls the execution of programs within the system  500  and provides scheduling, input-output control, file and data management, memory management, and communication control and related services. 
         [0041]    The I/O devices  510  may include input devices, for example but not limited to, a keyboard, mouse, scanner, microphone, etc. Furthermore, the I/O devices  510  may also include output devices, for example but not limited to, a printer, display, etc. Finally, the I/O devices  510  may further include devices that communicate via both inputs and outputs, for instance but not limited to, a modulator/demodulator (modem; for accessing another device, system, or network), a radio frequency (RF) or other transceiver, a telephonic interface, a bridge, a router, or other device. 
         [0042]    When the system  500  is in operation, the processor  502  is configured to execute the software  508  stored within the memory  506 , to communicate data to and from the memory  506 , and to generally control operations of the system  500  pursuant to the software  508 , as explained above. 
         [0043]    The embodiments described above, linked directly to solar hot air system technology, provide mechanisms for buildings to displace heating fuels, usually fossil fuels, with solar energy captured in a collector. The system design, installation, and financing allows customers to adopt these systems quickly, without upfront costs, and allows the system to be owned, maintained and operated by a third party. Such arrangements have never been considered for solar hot air systems because of the complication in creating a structure for 3 rd  party ownership where the energy is not easily metered, as can be done with electric and hot water systems. Such an arrangement allows the system owner to indirectly benefit the system host by leveraging tax incentives which lower the system&#39;s installation and equipment cost. If ownership passes to the host, for example, as an option under the contract, the host may benefit from a free fuel (sunlight) for the life of the system. With the addition of thermal storage, the system and the savings may be expanded by allowing the building to use thermal energy stored on site during times when the system overproduces. 
         [0044]    It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.