A system (500,700) for determining states of devices (320, 330, 340, 350, 360, 160, 165) in a building, the system (500,700) comprising: at least one computer comprising at least one processor and at least one memory, the at least one computer configured to: obtain a power monitoring signal by measuring an electrical property of a power line in the building, wherein the power line provides power to a first device and a second device in the building; determine a state of the first device by: a. processing a first power event of the power monitoring signal with a plurality of power models to generate a score for each power model of the plurality of power models, and b. selecting a state of the first device from a plurality of possible states using the scores; characterized in that the at least one computer is further configured to: receive first network data from a server computer, wherein the server computer transmitted the network data based on information received from the second device; determine, using the first network data, that the first network data corresponds to the second device; and select, using the first network data, a state of the second device from a plurality of possible states for the second device. at least one computer comprising at least one processor and at least one memory, the at least one computer configured to: obtain a power monitoring signal by measuring an electrical property of a power line in the building, wherein the power line provides power to a first device and a second device in the building; determine a state of the first device by: a. processing a first power event of the power monitoring signal with a plurality of power models to generate a score for each power model of the plurality of power models, and b. selecting a state of the first device from a plurality of possible states using the scores; obtain a power monitoring signal by measuring an electrical property of a power line in the building, wherein the power line provides power to a first device and a second device in the building; determine a state of the first device by: a. processing a first power event of the power monitoring signal with a plurality of power models to generate a score for each power model of the plurality of power models, and b. selecting a state of the first device from a plurality of possible states using the scores; a. processing a first power event of the power monitoring signal with a plurality of power models to generate a score for each power model of the plurality of power models, and b. selecting a state of the first device from a plurality of possible states using the scores; characterized in that the at least one computer is further configured to: receive first network data from a server computer, wherein the server computer transmitted the network data based on information received from the second device; determine, using the first network data, that the first network data corresponds to the second device; and select, using the first network data, a state of the second device from a plurality of possible states for the second device. receive first network data from a server computer, wherein the server computer transmitted the network data based on information received from the second device; determine, using the first network data, that the first network data corresponds to the second device; and select, using the first network data, a state of the second device from a plurality of possible states for the second device.