A hot water system might be set to keep water between 50°C and 60°C.
- If the water temperature is at or below 50°C, the water heater should be on.
- If the water temperature is at or above 60°C the water heater should be off.
Refrigerators, freezers, air-conditioners and space heaters can be automatically controlled having regard to:
- A lower temperature at which the appliance should be "on" (for heating appliances) and "off" (for cooling appliances)
- An upper temperature at which the appliance should be "off" (for heating appliances) and "on" (for cooling appliances)
- For any temperature that is between the lower and upper temperature, the appliance has a status of "Don't care if on or off".
|A ZigBee HVAC Application|
Controlling appliances in this way reduces the size and cost of energy storage.
- Excess energy being generated is added to any appliance that can use it.
- Peak energy use is lowered - when more energy is being used than is being generating - by automatically withholding supply from any appliance that can postpone its energy needs.
- When the battery charge is below 40 percent, charging should be "on".
- When the battery charge is at 100 percent, charging should be "off".
- When the battery charge is between 40 percent and 80 percent, charging can be considered to be "Don't care if on or off".
- When the battery charge is between 80 percent and 100 percent, the battery can be considered to be "Don't care if charging is on or off, OR if discharging is on or off". (That is to optionally SUPPLY energy to the home.)
A smart meter is not a requirement to implement such an energy management system.
|Integrated ZigBee low-cost controllers in a range of appliances from different manufacturers are a prerequisite.
If you are still connected to the grid, this level of control allows you to reduce the peak demand your household makes from the grid. This strategy helps:
- To reduce the need for network investment in extra poles and wires.
- To avoid the need for price increases for the electricity that you purchase from the electricity grid.