US 8,738,327 B2 
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munication may in the form of a signal sent over the power 
lines themselves, or a wireless communication over a data 
network arranged by the utility. These meters allow utilities to 
accomplish a number of goals, including offering pricing that 
varies by time of day in order to encourage customers to move 
consumption away from peak demand hours. These Smart 
meters can cost hundreds of dollars, however, and require 
both a “truck roll' a visit from a trained service person— and most likely the scheduling of an appointment with the 
occupants, because Swapping the meter will require turning 
off power to the house. 
If the utility installs a smart meter at each house that con 
tracts to participate in a PDR program, it may be possible to 
verify that the NC is in fact switched off. But this approach requires two separate pieces of hardware, two separate com 
munications systems, and the ability to match them for veri 
fication purposes. 
It would be desirable to have a system that could both 
implement and verify residential peak demand reduction with 
reduced expenses. 
SUMMARY OF THE INVENTION 
At least one embodiment of the invention that includes 
system for predicting the rate of change in temperature inside 
a structure comprising at least one thermostat located inside 
the structure and controlling an HVAC system in said struc 
ture; at least one remote processor that is in communication 
with said thermostat; at least one database for storing data 
reported by said thermostat; at least one processor that com 
pares outside temperature at at least location and at least one 
point in time to information reported to said remote processor 
from said thermostat, and wherein said processor uses the 
relationship between the inside temperature and the outside 
temperature over time to derive a first prediction for the rate of 
change in inside temperature assuming that the operating 
status of the HVAC system is “on”; and said processor uses 
the relationship between the inside temperature and the out 
side temperature over time to derive a second prediction for 
the rate of change in inside temperature assuming that the 
operating status of the HVAC system is “off”; and said pro 
cessor compares at least one of the first prediction and the 
second prediction to the actual inside temperature recorded 
inside the structure to determine whether the actual inside 
temperature is closer to the first prediction or the second 
prediction. 
In one embodiment, the invention comprises a thermostat 
attached to an HVAC system, a local network connecting the 
thermostat to a larger network Such as the Internet, one or more additional thermostats attached to the network and to 
other HVAC systems, and a server in bi-directional commu 
nication with the thermostats. The server logs the ambient 
temperature sensed by each thermostat vs. time and the sig 
nals sent by the thermostats to the HVAC systems to which 
they are attached. The server preferably also logs outside 
temperature and humidity data for the geographic locations 
for the buildings served by the connected HVAC systems. 
Such information is widely available from various sources 
that publish detailed weather information based on geo graphic areas such as by ZIP code. The server also stores other 
data affecting the load upon the system, Such as specific 
model of HVAC system, occupancy, building characteristics, 
etc. Some of this data may be supplied by the individual users 
of the system, while other data may come from commercial 
Sources such as the electric and other utilities who supply 
energy to those users. 
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By using these multiple data streams to compare the per 
formance of one system versus another, and one system ver 
sus the same system at other times, the server is able to 
estimate the effective thermal mass of the structure, and 
thereby predict the expected thermal performance of a given 
structure in response to changes in outside temperature. Thus, 
for example, if the air conditioning is shut off on a hot after 
noon, given a known outside temperature, it will be possible 
to predict how quickly the temperature in the house should 
rise. If the actual temperature change is significantly different 
from the predicted rate of change, or does not change at all, it 
is possible to infer that the air conditioning has not, in fact 
been shut off. 
This and other advantages of the present invention are 
explained in the detailed description and claims that make 
reference to the accompanying diagrams and flowcharts. 
BRIEF DESCRIPTION OF THE DRAWINGS 
FIG. 1 shows an example of an overall environment in 
which an embodiment of the invention may be used. 
FIG. 2 shows a high-level illustration of the architecture of 
a network showing the relationship between the major ele 
ments of one embodiment of the subject invention. 
FIG. 3 shows an embodiment of the website to be used as 
part of the subject invention. 
FIG. 4 shows a high-level schematic of the thermostat used 
as part of the Subject invention. 
FIG. 5 shows one embodiment of the database structure 
used as part of the Subject invention 
FIGS. 6A and 6B show a graphical representation of the 
manner in which the subject invention may be used to verify 
that a demand reduction event has occurred. 
FIG. 7 is a flow chart illustrating the steps involved in 
generating a demand reduction event for a given Subscriber. 
FIG. 8 is a flow chart illustrating the steps involved in 
confirming that a demand reduction event has taken place. FIG.9 is a representation of the movement of messages and 
information between the components of the subject inven 
tion. 
DETAILED DESCRIPTION OF THE PREFERRED 
EMBODIMENTS 
FIG. 1 shows an example of an overall environment 100 in 
which an embodiment of the invention may be used. The 
environment 100 includes an interactive communication net 
work 102 with computers 104 connected thereto. Also con 
nected to network 102 are one or more server computers 106, 
which store information and make the information available 
to computers 104. The network 102 allows communication 
between and among the computers 104 and 106. 
Presently preferred network 102 comprises a collection of 
interconnected public and/or private networks that are linked 
to together by a set of standard protocols to form a distributed 
network. While network 102 is intended to refer to what is 
now commonly referred to as the Internet, it is also intended 
to encompass variations which may be made in the future, including changes additions to existing standard protocols. 
When a user of the subject invention wishes to access 
information on network 102, the buyer initiates connection 
from his computer 104. For example, the user invokes a 
browser, which executes on computer 104. The browser, in 
turn, establishes a communication link with network 102. 
Once connected to network 102, the user can direct the 
browser to access information on server 106. 
Appx99
Case: 23-1101 Document: 15 Page: 134 Filed: 05/09/2023