Energy saving opportunities - Smart Panels
From Electrical Installation Guide
Smart Panels are distribution switchboards which include the 3 key functions:
- Measure, with embedded and stand-alone metering and control capabilities,
- Connect, with integrated communication interfaces, ready to connect the electrical distribution system to energy management platforms,
- Save, i.e. provide Energy Efficiency benefits, through real-time monitoring and control, and access to on-line services.
With embedded metering devices, Smart Panels are the natural source of data within the electrical installation. Information can be made available on local display, or sent via communication network.
Interface devices are implemented so that communication is made simple and easy to install. The most advanced and efficient technologies are used:
- Modbus: for transmission of information inside switchboards, between components,
- Ethernet cable or wifi: inside buildings, connecting switchboard with computers,
- Ethernet on DSL/GPRS: connecting the electrical distribution system to on-line services.
How Smart Panels contribute to Energy Efficiency?
Smart Panels are designed to monitor electricity in the installation right at the sources. This is the best way to know how energy is used. They are adapted to a large range of power: from final distribution, up to the main distribution board. They offer large possibilities of visualization, from local, up to cloud based integrated solution.
They provide on-site real time monitoring and control. The most essential information can be displayed locally: power, energy consumption, status of equipment, alarms… Control of switchgear is also possible: open, close, reset of protection devices…
Key data and functions are provided on local screen, on-site computer, remote control room or cloud-hosted platform:
- Detect demand peaks or abnormal energy usage,
- Plan long term energy usage,
- Provide trends on energy consumption, making savings possible,
- Provide information for corrective, preventive or predictive maintenance.
Information is made available on PC for the site manager using web pages accessible with standard browser. Access is also given to external experts for analysis and optimization.
Examples of architectures with Smart Panels
Systems for monitoring and energy control are physically very similar and overlap with the electrical distribution architecture whose layout they often replicate.
The arrangements shown in Figure K29 to Figure K31 represent possible examples and reflect the requirements typically associated with the distribution involved (in terms of feeder numbers, the amount and quality of energy required, digital networks, management mode, etc.). They help to visualise and explain all the various services which can be used to promote energy efficiency.
In addition, these diagrams make it clear that the choice of components is determined by the choice of architecture (for example, the sensors must be compatible with the digital bus). The reverse can also happen, however, if a technicoeconomic assessment of components installation costs and expected results shows that a different architecture is more cost-effective. In fact, the cost (in terms of purchase and installation) of these components, which sometimes have the same name but different characteristics, may vary widely and produce very variable results:
- A metering device can measure one or more parameters with or without using calculations (energy, power, cos φ).
- Replacing a standard circuit breaker with a circuit breaker containing an electronic control unit can provide a great deal of information on a digital bus (effective and instantaneous measurements of currents, phase-to-neutral and phase-to-phase voltages, imbalances of phase currents and phase-to-phase voltages, frequency, total or phase-specific active and reactive power, etc.).
When designing these systems, therefore, it is very important to define objectives for energy efficiency and be familiar with all the technological solutions, including their respective advantages, disadvantages and any restrictions affecting their application (see Fig. K33).
To cover all the various scenarios, it may be necessary to search through various hardware catalogues or simply consult a manufacturer offering a wide range of electrical distribution equipment and information systems. Certain manufacturers, including Schneider Electric, offer advisory and research services to assist those looking to select and implement all these various pieces of equipment.
|Energy savings||Cost optimisation||Availability and reliability|
|Variable speed drives||+++||+||+|
|High-performance motors and transformers||+++|
|Supply for MV motors||+++|
|Power factor correction||+||+++|
|Outage-free supply devices||+++|
|Architecture based on intelligent equipment Level 1||++||+|
|Specialised, centralised architecture for electricians Level 2||+++||++||+|
|General/conventional, centralised architecture Level 3||+||++||+++|
Fig. K33: Solutions chart