Technologies that make cities smarter and better to live in
A key strategy for a more efficient and sustainable society in metro areas is the smart city concept, which introduces innovative applications in municipalities, utilities, transportation, and public services. For example, a smart city could reduce energy usage by employing smart meter technology—adding a connectivity infrastructure to easily monitor and control final user power consumption and energy grid loss; and introduce remote public light management services to a municipality for street lights by adding sensors and connectivity, thereby optimizing energy consumption and reducing maintenance costs; and using that same connectivity communication system to improve overall life quality by adding other multi-services for security, air and water pollution monitor and control, or even smart parking and smart waste management. On that score, improving the efficiency of garbage collection mainly in suburbs area, a smart system for waste management could send a pick-up request when a dumpster is full and needs to be emptied. A smart parking system could monitor parking spaces and direct drivers to open parking places, or offer the possibility to book a spot in advance.
The Internet of Things, the IoT, is a network of smart nodes, mostly low-power and low-cost sensor nodes, which senses data and communicates information to a cloud, without the need of direct human interaction. The web cloud collects, processes, and protects this information as data, and only shares it with designated people or as it pertains to provide services to utilities. The main target of the IoT is to use this technology to improve the day by day quality of life.
This IoT scenario includes four main application areas: Wearables, Smart Homes, Smart Cars, and Smart Cities. Smart city applications are emerging as driving markets in the Internet of Things trend. The smart cities scenario includes smart buildings, smart metering, street lighting monitor and control, traffic and mobility management, smart parking, environmental monitoring, smart garbage collection, and smart health services.
The wearable concept involves smart glasses, smart bands, and smart watches, as used in fitness and healthcare applications. The smart homes topic includes indoor smart lighting, smart appliances, and smart-plugs for energy monitor and control, safety, and security. The smart car idea introduces the concept of connectivity inside the vehicle to provide several services to the driver, such as remote diagnostics, real-time traffic information, and location-based services.
The topics of smart cars, wearables, and smart homes are excluded from this particular discussion.
The smart meters concept was one of the first successful trends in the Smart City scenario. The smart meter has assumed a key role thanks to Automatic Meter Reading (AMR), one way communications, and Automatic Meter Infrastructure (AMI), two way communications. The AMI makes it possible to exchange bidirectional data from each user meter to the appropriate Energy Service Provider, and exchange information about energy consumption and energy locally produced. With this technology, the Energy Service Provider can remotely read energy consumption in real time, collect information from all the meters to know the total energy load profile, dynamically select special price tariffs in agreement with the user, as well as monitor and maintain the complete system while also preventing faults and energy loss.
In these scenarios, communication is the key factor of a Smart Meter Infrastructure. Whether by Power Line Communication (PLC) or by wireless communication, by creating a local network, the smart meter would be able to send information to a data-concentrator where the data is collected and periodically shared with the Energy Service Provider. In the same case, the smart meter can also transmit using cellular network.
Power Line Communication (PLC) Technology is typically used for Energy Power Meters. For narrow band Power Line Modems, (PLM), there are several communication network protocols such as IEC 61334-5-1, Meters and More, PRIME, G3-PLC, as example.
In Europe, the European Committee for Electrotechnical Standardization (CENELEC) has defined carrier frequency bands to be used for power line communication: Band A is only for energy providers (from 9 to 95 KHz), Band B – C – D is open for end use applications (from 95 to 148.6 KHz). In the US, the Federal Communications Commission (FCC) have designated FCC Bands 10 KHz to 490 KHz, in China the Electric Power Research Institute (EPRI) have bands 3 to 90 KHz, and in Japan, the Association of Radio Industries and Businesses (ARIB) has bands 10 KHz to 450 KHz.
An international non-profit association comprised of leading technology companies and utilities, Meters and More, has developed an open specification protocol. The protocol provides efficiency, robustness, and security of communications, using n-PSK modulation to achieve a coded bit-rate up to 4.8kbps with automatic network configuration and management.
The PoweRline Intelligent Metering Evolution alliance, or PRIME, has defined an open narrow-band power line communication protocol using OFDM (Orthogonal Frequency Division Multiplexing) in combination with DPSK (Differential Phase Shift Keying) modulation in frequency. It employs self-organized network methodology to provide transparent communication services between concentrator and meters, and in a previous release, PRIME was working on carrier frequencies from 42 to 89 kHz, within CENELEC’s A band, with a data rate up to 128.8Kbps in D8PSK. There is a new release ongoing, designated 1.4, working at higher carrier frequencies (up to 471 kHz) in ARIB and FCC bands, with possible data rates up to 1Mbps.
The G3-PLC protocol, defined by G3-PLC™ Alliance, is similar to the PRIME protocol, working with PSD (power spectral density) in combination in DPSK in time on carrier frequencies from 35 to 91 kHz, with data rates up to 33.4 kbps in DQPS. The G3 protocol provides adaptive subcarrier allocation, offering the possibility to switch off sub-bands affected by communication noise.
As the numerous protocols attest, the trend is to implement a unique platform Smart Meter and PLC using a system-on-chip approach to meet the needs of specific protocols.
In same case for power meter are used also Wireless Communication technology, same that is used for gas and water meters, explained the follow paragraph