Patent Number: 
Section: claims

1. A method of determining dehumidifier performance, the method comprising:determining a first humidity value of airflow entering the dehumidifier;measuring an electrical current drawn by the dehumidifier;using the measured electrical current, determining an efficiency of the dehumidifier;based at least in part on the efficiency of the dehumidifier, determining a second humidity value of airflow exiting the dehumidifier; anddetermining, with a processor, a difference between the first humidity value and the second humidity value. 2. The method of claim 1, further comprising:measuring a first temperature of airflow entering the dehumidifier;measuring a first relative humidity of airflow entering the dehumidifier, wherein determining the first humidity value comprises calculating the first humidity value based at least in part on the first temperature and the first relative humidity; anddetermining the efficiency of the dehumidifier based at least in part on a moisture removal rate of the dehumidifier. 3. The method of claim 2, further comprising measuring a second temperature of airflow exiting the dehumidifier and determining an enthalpy of airflow exiting the dehumidifier, wherein determining the second humidity value comprises determining the second humidity value based at least in part on the efficiency, the second temperature, and the enthalpy of airflow exiting the dehumidifier. 4. The method of claim 1 wherein determining the second humidity value comprises determining the second humidity value based at least in part on the efficiency of the dehumidifier and an energy balance of the dehumidifier. 5. The method of claim 1 wherein determining the second humidity value comprises determining the second humidity value based at least in part on the efficiency of the dehumidifier and a mass flow balance of moisture and air passing through the dehumidifier. 6. The method of claim 1 wherein determining the first humidity value comprises:measuring a first temperature of airflow entering the dehumidifier;measuring a first relative humidity of airflow entering the dehumidifier; andcalculating the first humidity value based on the first temperature and the first relative humidity. 7. The method of claim 1 wherein determining the second humidity value comprises determining the second humidity value without measuring a relative humidity of airflow exiting the dehumidifier. 8. The method of claim 1 wherein determining the efficiency of the dehumidifier further comprises determining the efficiency based at least in part on a moisture removal rate of the dehumidifier. 9. The method of claim 1 wherein determining the second humidity value comprises determining an enthalpy of airflow exiting the dehumidifier, wherein the enthalpy is based at least in part on the efficiency of the dehumidifier. 10. The method of claim 1 wherein the first humidity value is a first humidity ratio of a first mass of moisture and a first mass of dry air entering the dehumidifier, and the second humidity value is a second humidity ratio of a second mass of moisture and a second mass of dry air exiting the dehumidifier. 11. The method of claim 1, further comprising providing a performance value of the dehumidifier based on at least one of a moisture removal rate and energy consumed by the dehumidifier. 12. A method of evaluating dehumidifier performance, the method comprising:measuring an inlet temperature of airflow at an inlet of a dehumidifier;measuring a relative humidity of airflow at the inlet of the dehumidifier;determining an inlet humidity ratio of airflow at the inlet of the dehumidifier based on the inlet temperature and the inlet relative humidity;determining an outlet humidity ratio of airflow at an outlet of the dehumidifier using an efficiency of the dehumidifier, and wherein the efficiency is determined using a measured electrical current drawn by the dehumidifier; andcomparing, with a processor, the inlet humidity ratio with the outlet humidity ratio to determine an amount of moisture removed by the dehumidifier from airflow passing through the dehumidifier. 13. The method of claim 12 wherein determining the outlet humidity ratio comprises determining the outlet humidity ratio based at least in part on the efficiency based at least in part on a moisture removal rate and current drawn by the dehumidifier. 14. The method of claim 12, further comprising determining the efficiency of the dehumidifier based at least in part on a moisture removal rate and current drawn by the dehumidifier. 15. The method of claim 12, further comprising:measuring an outlet temperature of airflow at the outlet of the dehumidifier; anddetermining an outlet enthalpy of airflow at the outlet of the dehumidifier based at least in part on the efficiency of the dehumidifier, wherein determining the outlet humidity ratio comprises determining the outlet humidity ratio based at least in part on the outlet temperature and the outlet enthalpy. 16. The method of claim 12 wherein determining the outlet humidity ratio comprises determining the outlet humidity ratio based at least in part on a mass flow balance of moisture and air passing through the dehumidifier. 17. The method of 16, further comprising determining the efficiency of the dehumidifier based at least in part on a moisture removal rate of the dehumidifier. 18. A method of determining dehumidifier performance, the method comprising:determining a first humidity ratio of airflow entering the dehumidifier based at least in part on an inlet temperature and a relative humidity of airflow entering the dehumidifier;measuring an electrical current drawn by the dehumidifier;using the measured electrical current, determining an efficiency of the dehumidifier based on a moisture removal rate of the dehumidifier;determining a second humidity ratio of airflow exiting the dehumidifier based at least in part on the efficiency of the dehumidifier, wherein the second humidity ratio is determined without measuring an outlet relative humidity of airflow exiting the dehumidifier; andcomparing, with a processor, the first humidity ratio and the second humidity ratio. 19. The method of claim 18 wherein determining the second humidity ratio includes determining the second humidity ratio based on at least one of an energy balance of the dehumidifier and a mass flow balance through the dehumidifier. 20. An apparatus for determining a performance of a dehumidifier that includes a moisture removal device, the apparatus comprising a computer readable medium having stored instructions thereon that, when executed by a computing device, cause the computing device to perform a method to:determine a first humidity value of airflow upstream from the moisture removal device;measure an electrical current drawn by the dehumidifier;using the measured electrical current, determine an efficiency of the dehumidifierdetermine a second humidity value of airflow downstream from the moisture removal device, wherein the second humidity value is based at least in part on the efficiency of the dehumidifier; andcompare the first and second humidity ratios. 21. The apparatus of claim 20 wherein the computer-readable medium further includes instructions to:receive a first value corresponding to a first temperature of airflow upstream from the moisture removal device;receive a second value corresponding to a relative humidity of airflow upstream from the moisture removal device; anddetermine the first humidity value based at least in part on the first temperature and the relative humidity. 22. The apparatus of claim 21 wherein the computer-readable medium further includes instructions to receive a third value corresponding to the efficiency of the dehumidifier based on at least in part on a moisture removal rate of the dehumidifier. 23. The apparatus of claim 21, further comprising a housing at least partially surrounding the dehumidifier, wherein the computer readable medium is carried by the housing. 24. The apparatus of claim 23, further comprising:a first sensing module carried by the housing proximate to an inlet through which airflow enters the dehumidifier, wherein the first sensing module detects the first temperature and the relative humidity of the airflow;a second sensing module carried by the housing proximate to an outlet through which airflow exits the dehumidifier, wherein the second sensing module detects a second temperature of the airflow after the airflow passes the evaporator; anda processing module carried by the housing and configured to calculate the first humidity value, the second humidity value, and the difference between the first and second humidity values. 25. The apparatus of claim 20 wherein the apparatus is a portable apparatus that is movable relative to the dehumidifier. 26. The apparatus of claim 20, further comprising:a sensing module configured to determine at least one of a first temperature and a first relative humidity of airflow upstream from the moisture removal device, and a second temperature of airflow downstream from the moisture removal device; anda processing module to determine the first relative humidity, the second relative humidity, and a difference between the first relative humidity and the second relative humidity. 27. A method of determining dehumidifier performance, the method comprising:determining a first humidity value of airflow entering the dehumidifier;measuring an electrical current drawn by the dehumidifier;using the measured electrical current of the dehumidifier and an empirical performance factor, determining a second humidity value of airflow exiting the dehumidifier; anddetermining, with a processor, a difference between the first humidity value and the second humidity value.