Smart metering with ZigBee

BANGALORE, INDIA: India's energy demands are skyrocketing and metering them smartly is the need of the hour.

“In India, thanks to high GDP rate and growing middle-class population, the energy demands are growing at high pace and as usual power generation lags behind it,” says Venki Venkataraman, head, Wireless Practice, Mindteck (India). He was speaking to CIOL in an interview recently. Excerpts:

The company has been a member of ZigBee Alliance since 2004 and provides engineering services on ZigBee protocol stack and smart energy profile development, network management system, network configuration tools and Smart Energy management products and systems.

CIOL: What is Smart Energy and how will ZigBee provide a solution?

Venki Venkataraman: Smart Energy is an advanced metering technology designed for efficient generation and consumption of energy sources such as electricity, gas and water.

The smart energy system consists of automated meter reading (AMR), real-time energy pricing and control of energy load by the consumer and utility companies. The smart energy technology is applicable to residential, commercial and industrial segments. Smart energy system needs bi-directional control and data communication network from utility companies to energy consuming devices.

Major energy consuming appliances in a typical home are refrigerator, electric oven, water heaters, A/C equipments and washing machine. These devices and electricity (or gas and water) meter need to be networked for communication, in order to achieve energy usage efficiency.

These networks are called Home Area Network (HAN) and, ZigBee, which is a low-cost, low-power, wireless mesh networking standard based on EEE 802.15 "wireless personal-area networks," or WPANs, meant for wireless sensor network applications, fits well to build HAN.

CIOL: What is the scope of this technology in India?

VV: ZigBee’s growth in India is very nascent, but is catching up! In India, the market is more focused on automated metering reading for billing and meter management and to prevent power theft. Pretty soon, I expect this market will evolve into full blown Smart Grid Management system.

The wired technologies have limitations due to high cost of wire installation, maintenance and scaling. In India, the technology needs to be implemented in two stages.

The first stage should start with real-time meter reading known as Automated Meter Reading (AMR) which will involve, building data communication infrastructure from consumer space to utility companies. This would help energy generating utility companies and transmission and distribution sub-stations to monitor consumption at real-time and adjusts peak energy load manually.

Next stage should involve networking other energy consuming appliances within a home, to the Smart Grid network. This stage will focus on controlling energy consumption by consumer and by energy generating utility or regulatory authorities.

CIOL: What are the advantages of ZigBee smart meter?

VV: ZigBee based devices are typically battery operated as they consume very less energy. Their long battery life, self healing and self forming mesh network and in-built support for security and smart energy applications, scores high compared to other sensor network protocols.

Since the technology is based on wireless, the installation and maintenance become easier. The typical installation cost savings of ZigBee based devices compared to wired devices are in the range of 30 per cent.

It improves energy efficiency by monitoring energy consumption at real time and by adjusting peak load consumption automatically. Within Home Area Network, appliances communicate using ZigBee.

The HAN network is connected to transmission and distribution (T&D) centre through cellular/WiFi technologies. The T&D centre is connected to Energy Utility network through long-range wireless communication technologies.

CIOL: What are the emerging trends in this space?

VV: In the residential HAN space, one would see other energy consuming appliances such as Power Hybrid Electric Vehicle (PHEV) getting added to the network. The Energy harvesting devices such as solar cell and windmill also will be added. The power generated by these energy harvesting devices will be subsumed within the consumer space and excess power will be fed back to the electric grid.

In the government-managed civic utility energy space, one would see street lighting management applications integrated into smart grid network.

In the commercial energy space, you will see commercial building lighting and HVAC network, IT data centre network, commercial solar panel power harvest network and electric vehicle charging stations network.

CIOL: Going forward, what kind of challenges do you see?

VV: The current ZigBee doesn’t support native IP communication protocol and its application objects, application protocol and security mechanisms are ZigBee specific. These limitations are being addressed in the new spec ZigBee + HomePlug Smart Energy Profile 2.0, which will have IETF compliant IP protocol support in ZigBee stack, will define IEC compliant App objects and will support W3C compliant Application Protocol communication.

Another factor is the price of ZigBee chip set, which is around $3 to $4 and for the technology’s mass adoption this should come down significantly! With growing adoption of ZigBee, one would require automatic tools to identify, configure and deploy smart energy devices and network. One also requires tools to monitor and control the smart grid network for operational efficiencies.