Domestic electric energy control

• US 5,956,462 A
• Filed: 09/24/1997
• Issued: 09/21/1999
• Est. Priority Date: 09/26/1996
• Status: Expired due to Fees

• Current Assignee: Aquabeat Pty Limited
• Original Assignee: Aquabeat Pty Limited
• Inventors: Langford, Newton
• Primary Examiner(s): Walberg, Teresa
• Assistant Examiner(s): CAMPBELL, THOR S
• Application Number:
  US08/936,816
• Time in Patent Office: 727 Days
• Field of Search: 392/449, 392/450-454, 392/498, 340/870.17, 307/31-35, 307/38-40, 307/96-97
• US Class Current: 392/449
• CPC Class Codes: F24D 2220/042 Temperature sensors
• CPC Class Codes: F24D 2240/26 Vertically distributed at fixed positions, e.g. multiple sensors distributed over the height of a tank, or a vertical inlet distribution pipe having a plurality of orifices
• CPC Class Codes: F24H 15/144 Measuring or calculating energy consumption
• CPC Class Codes: F24H 15/168 Reducing the electric power demand peak
• CPC Class Codes: F24H 15/225 at different heights of the tank
• CPC Class Codes: F24H 15/37 of electric heaters
• CPC Class Codes: F24H 15/407 using electrical switching, e.g. TRIAC
• CPC Class Codes: F24H 15/414 using electronic processing, e.g. computer-based
• CPC Class Codes: F24H 15/443 using a central controller connected to several sub-controllers
• CPC Class Codes: F24H 9/2021 Storage heaters
• CPC Class Codes: G05D 23/1923 using thermal energy, the cost of which varies in function of time
• CPC Class Codes: H02J 13/00004 characterised by the power network being locally controlled
• CPC Class Codes: H02J 13/00022 using wireless data transmission
• CPC Class Codes: H02J 2310/14 The load or loads being home appliances
• CPC Class Codes: H02J 3/14 by switching loads on to, or off from, network, e.g. progressively balanced loading
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02B 70/3225 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y04S 20/222 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 20/244 : the home appliances being or involving heating ventilating and air conditioning [HVAC] units
• CPC Class Codes: Y04S 40/126 : using wireless data transmission

Abstract

An electric power distribution system that utilises radio signals from the power distributor to an appliance such as a water heater 1, to inform via a receiver 12, a micro processor 10 of the energy priority rating of the power distributor. The water heater has an array of temperature sensors 5 that determines the average temperature of the tank and enables the microprocessor 10 to generate an energy needs rating for the water heater. The microprocessor is programmed with a decision algorithm that uses the needs and priority ratings to either switch the appliance on or off.

Claims

1. A power distribution system for electric water heaters comprising

a) a plurality of electric water heaters each including a storage tank, a heating element, a thermostat, a set of operational settings and a power switch;

b) a central controller at a power utility having means to monitor power consumption and calculate a power availability priority;

c) a transmitter associated with said central controller for broadcasting signals containing data representative of said power availability priority calculated at said central controller;

d) sensing means on each of said water heaters for sensing the temperature of the water stored in the storage tank of said water heater;

e) a data processor connected to said water heater programmed to process water temperature data generated by said sensing means and said operational settings of said water heater to generate an energy need category code for said water heater; and

f) a receiver connected to said data processor to receive said power availability priority data signals sent from said transmitter;

g) said data processor connected to said water heater being programmed in accordance with a predetermined decision algorithm to decide whether to switch the water heater on or off jointly based on both said energy need category code generated by said data processor connected to said water heater and the power availability priority data by said receiver.

2. A power distribution system as claimed in claim 1 wherein said predetermined decision algorithm is X=P-N, wherein P is a power availability priority category code transmitted from said central controller and N is said energy need category code generated by said data processor connected to said water heater, a value of X greater than or equal to 1 resulting in said power switch at the water heater being switched on and a value of X equal to zero or a negative number resulting in said power switch at the water heater being switched off.

3. A water heater controller for a water heater which includes a storage tank, a heating element, a set of temperature sensors in a wall of the water heater storage tank, a set of operational settings and a water heater power switch, said controller including

a) a data processor connected to said water heater programmed to process temperature data provided from said sensors and said operational settings of the water heater to generate an energy need category code for the water heater;

and

b) a receiver connected to said water heater to receive power availability data from a remote power utility to be used by said data processor;

c) said data processor connected to said water heater being programmed to decide how to operate said power switch jointly based on both said energy need category code calculated for the water heater and said power availability data received by said receiver from the remote power utility.

4. A water heater controller as claimed in claim 3 wherein said data processor connected to said water heater is programmed to operate in accordance with a decision algorithm X=P-N, wherein P is a priority category established by the remote power utility and provided in said power availability data from the remote power utility, and N is said energy need category code generated by said data processor connected to said water heater;

a value of X greater than or equal to 1 resulting in said water heater power switch being switched on, and a value of X equal to zero or a negative number resulting in said water heater power switch being switched off.

5. A water heater controller as claimed in claim 4 wherein said water storage tank has said heating element located in a lower portion of said storage tank and a hot water outlet located in an upper part of said storage tank, said storage tank being arranged to have stratified layers of water of different temperatures with the hottest strata being adjacent said hot water outlet.