Determining Thermal Parameters Of A Building

Abstract

Embodiments of the present disclosure include techniques for determining thermodynamic properties of buildings. In one embodiment, a method for determining a building UA-value comprises monitoring indoor and outdoor air temperature during a drift phase over a first time period, and monitoring a temperature control system run time during a second time period over which the temperature control system in the building restores indoor air conditions to an initial state at the beginning of the first time period. Additionally, an amount of heat energy change may be determined during the second time period. Embodiments may determine thermal resistance of the building from data obtained during over the two time periods, for example.

What is claimed is: 
     
         1 . A method for determining a building UA-value comprising:
 monitor indoor and outdoor air temperature during a drift phase over a first time period;   monitor a temperature control system run time during a second time period when the temperature control system in the building restores indoor air conditions to an initial state at the beginning of the first time period; and   determining the amount of heat energy change during the second time period.   
     
     
         2 . The method in  claim 1  wherein data for the internal and external air temperature, the temperature control system run time, and amount of heat energy change is used to determine a combined UA-value of the building and thermal energy distribution system. 
     
     
         3 . The method of  claim 6  wherein the combined UA-value is used to determine peak heating or cooling loads for the building. 
     
     
         4 . The method of  claim 1  wherein said monitoring steps use a data acquisition unit with an internet-connected thermostat. 
     
     
         5 . A method for determining thermodynamic behavior of a building comprising:
 during a first time period,
 measuring, from a first sensor located inside said building, a plurality of internal temperature values; and 
 measuring, from one or more second sensors located outside of, but proximate to, said building, a plurality of external temperature values, 
 wherein the plurality of internal temperature values correspond to a change in temperature inside the building from a first temperature to a second temperature during the first time period; 
   activating a temperature control system to change the temperature inside the building from the second temperature to the first temperature;   determining a duration of a second time period over which the temperature inside the building changes to meet the first temperature; and   determining a thermodynamic property of the building is based on at least said measuring steps and said determining step.   
     
     
         6 . The method in  claim 5  wherein determining the thermodynamic property of the building is based at least on initial and final internal temperature values, initial and final external temperature values, a duration of the first time period, a known energy capacity of the temperature control system, and a duration of the second time period. 
     
     
         7 . The method of  claim 5  wherein determining further comprises calculating one or more average differences between the plurality of internal temperature values and the plurality of external temperature values. 
     
     
         8 . The method of  claim 5  further comprising, prior to said first time period, maintaining a constant temperature inside the building to establish a temperature equilibrium between the temperature inside the building and the temperature outside the building. 
     
     
         9 . The method of  claim 5  wherein the temperature inside the building at the beginning of the first time period is approximately equal to the temperature inside the building at the end of the second time period. 
     
     
         10 . The method of  claim 5  wherein the first sensor is a thermostat. 
     
     
         11 . The method of  claim 5  wherein the thermodynamic property is a thermal resistance. 
     
     
         12 . The method of  claim 5  wherein the thermodynamic property is a peak heating load. 
     
     
         13 . The method of  claim 5  wherein the thermodynamic property is a peak cooling load. 
     
     
         14 . The method of  claim 5  wherein the plurality of internal temperature values are greater than the plurality of external temperature values, and wherein the temperature control system increases the temperature inside the building. 
     
     
         15 . The method of  claim 5  wherein the plurality of internal temperature values are less than the plurality of external temperature values, and wherein the temperature control system decreases the temperature inside the building. 
     
     
         16 . The method of  claim 5  wherein the temperature control system is a heating, ventilation, or air conditioning system. 
     
     
         17 . The method of  claim 5  wherein the one or more second sensors are from a weather station. 
     
     
         18 . The method of  claim 5  further comprising, during the first time period, measuring one or more internal humidity values and one or more external humidity values. 
     
     
         19 . The method of  claim 5  further comprising monitoring electricity consumption of the building during the first and second time periods, wherein determining the thermodynamic property of the building is further based on said electricity consumption. 
     
     
         20 . The method of  claim 5  further comprising determining solar energy absorption of the building during the first and second time periods, wherein determining the thermodynamic property of the building is further based on said solar energy absorption. 
     
     
         21 . A system for determining thermodynamic behavior of a building comprising:
 one or more processors;   one or more network interface units;   a non-transitory computer readable medium having stored thereon one or more programs, which when executed by the one or more processors, causes the one or more processors to perform a method comprising:   during a first time period,
 measuring, from a first sensor located inside said building, a plurality of internal temperature values; and 
 measuring, from one or more second sensors located outside of, but proximate to, said building, a plurality of external temperature values, 
 wherein the plurality of internal temperature values correspond to a change in temperature inside the building from a first temperature to a second temperature during the first time period; 
   activating a temperature control system to change the temperature inside the building from the second temperature to the first temperature;   determining a duration of a second time period over which the temperature inside the building changes to meet the first temperature; and   determining a thermodynamic property of the building based on at least said measuring steps and said determining step.   
     
     
         22 . A non-transitory computer readable medium having stored thereon one or more programs, which when executed by the one or more processors, causes the one or more processors to perform a method comprising:
 during a first time period,
 measuring, from a first sensor located inside said building, a plurality of internal temperature values; and 
 measuring, from one or more second sensors located outside of, but proximate to, said building, a plurality of external temperature values, 
 wherein the plurality of internal temperature values correspond to a change in temperature inside the building from a first temperature to a second temperature during the first time period; 
   activating a temperature control system to change the temperature inside the building from the second temperature to the first temperature;   determining a duration of a second time period over which the temperature inside the building changes to meet the first temperature; and   determining a thermodynamic property of the building based on at least said measuring steps and said determining step.