Our response to critical challenges
Under Frequency Load Management
Special circuitry installed within three phase/HT/MV meters, and installed on feeders, and distribution transformers continuously monitors frequencies and reacts with 70ms to frequency variations nearing full capacity by activating a digital output to connect or reconnect certain lines exceeding configurable value. Automatic reconnection occurs after a configurable period if power consumption is within limits. Customizable limits are configured remotely on individual or groups of consumers.
Utilities typically installed expensive (000’s of USD) under-frequency devices within the sub-stations, which disconnected high voltage lines, and disconnected all consumers at the same time. This general disconnection caused a massive energy pulse created by the immediate disconnection of a sizeable load in zero time. It caused instability in the grid and significant fluctuations in the demand side as a result.
The implementation of under frequency meters over the Low/Medium Voltage network, disconnects individual consumers /loads (direct or CT connection) at varying frequency levels. The disconnection levels are remotely configured from within the MDM system software, and each customer can be predefined by a different frequency value. This allows differentiated and graduated load shedding for more balanced load management. With the ability to randomly configure the disconnection under-frequency threshold for each customer, black-outs will not affect the same consumers as is common practice until now. With the ability to load limit each individual consumer separately, utilities have the option to offer preferred/at risk supply contracts and charge premiums/give discounts accordingly.
Load Control Elements
Industrial and commercial customers where significant non-critical power usage justifies the cost, load control devices (APM) with a relay, isolate and disconnect non-critical machinery remotely. The machinery/appliances themselves do not need any smart nodes built–in, the remote disconnection and sub-sequent reconnection are enabled by the din-rail APM device which communicates via the smart meter to disconnect specific lines. The devices can be part of a direct load control program which provides the ability for utilities cycle machinery such as air conditioners and water heaters on and off during periods of peak demand in exchange for a financial incentive/lower electric bills.
I-max is a predefined setting within the smart meters which protects the circuit breakers belonging to the utility. If consumption exceeds a critical threshold (i.e. 100 amps) automatic disconnection occurs.
I-critical is a predefined setting within the smart meters which imposes electricity usage limits (i.e. automatic disconnection above 60 amps) when the transformer is supplying near maximum capacity. Customers can be limited at varying power levels, with preferential values assigned to priority customers (frail/elderly and emergency services).
Multi-Tariff Support – TOU/Step Inclined Tariff
Implemented in the system is multi- tariff support (time of use and step-inclined tariff) providing an opportunity for consumers to play a significant role in the operation of the electric grid by reducing or shifting their electricity usage during peak periods in response to time-based rates for balancing supply and demand. Power-C Metering Africa is also working on advanced methods of engaging customers in demand response efforts including supply/demand based rates such as critical peak pricing, dynamic pricing, and critical peak rebates.
In-Home Displays and Customer Portal
Consumers have access to their real-time consumption data via Power-C Metering Africa’s online customer portal and In-Home Displays. These energy efficiency measures provide readily available information to the consumers of their current tariff and cost, as well as the option for utilities to communicate real-time pricing variations to (dis)incentivize consumption for a more balanced load.