By ADITHYA JAYAPRAKASH

AGENDA

• RECAP • CHALLENGES OF IoT• BATTERY LIFE• EXISTING SYSTEM• DIFFERENT TECHNOLOGY TO POWER IoT DEVICES• ENERGY HARVESTING • POWER MANAGEMENT • THINGS TO CONISDER • FUTURE WORK • CONCLUSION • REFERENCES

RECAP

The Internet of Things (IoT) is the network of physical objects—devices, vehicles, buildings and other items embedded with electronics, software, sensors, and network connectivity—that enables these objects to collect and exchange data.

CHALLENGES OF INTERNET OF THINGS (IoT)

Lack of Shared Standards and Infrastructure.

Data control and access.

Data security.

Battery life.

BATTERY LIFE

It is estimated that there will be twenty-four billion connected devices by the year 2020.

Currently, majority of the connected devices run on batteries, which have limited shelf life.

Given current energy availability, powering these devices will be impossible.

EXISTING SYSTEM

1. Sensors are powered either through in-line connections or batteries.

2. In-line power sources are constant but may be impractical or expensive in many instances.

3. Batteries may represent a convenient alternative, but battery life, charging, and replacement, especially in remote areas, may represent significant issues.

4. The technical and practical challenges facing energy storage in emerging IoT electronics cannot be met by any one incumbent technology.

DIFFERENT TECHNOLOGIES TO POWER IoT DEVICES

ENERGY HARVESTING

• Energy harvesting technologies use power generating elements such as solar cells, piezoelectric elements, and thermoelectric elements to convert light, vibration, and heat energy into electricity, then use that electricity efficiently.

• Although a number of energy harvesting technologies have been proposed and presented in the context of IoT recently, radiant and thermoelectric sources are the most engineering-viable options to power or charge a small electronic system.

POWER MANAGEMENT

Devices connected to a network consume power, and providing a continuous power source is a pressing concern for the IoT.

Depending on the application, a combination of techniques such as power-aware routing and sleep-scheduling protocols can help improve power management in networks.

Power-aware routing protocols determine the routing decision based on the most energy-efficient route for transmitting data packets.

Sleep-scheduling protocols define how devices can “sleep” and remain inactive for better energy efficiency without impacting the output.

THINGS TO CONSIDER

• Different Markets, Different Requirements

• Battery Efficiency and Wireless - Not Always an Obvious Choice

• Duty Cycle - How Often Does the Device Communicate?

• Space Constraints and Stored Power in the Design

FUTURE WORK Harvesting small scale energy from otherwise wasted ambient energy sources has attracted immense research efforts for battery-powered wireless sensor networks for various applications such as structural health monitoring, industrial condition monitoring and healthcare. The power level which those applications may reach ranges from microwatts to milliwatts. Energy scavenged from ambient sources may be able to recharge or even eliminate the battery to power up those devices perpetually.

Sources of energy for harvesting include, but are not limited, to light, thermal gradient, vibration, and radio frequency radiation.

Energy storage devices like rechargeable batteries or supercapacitors and efficient power management circuitry are indispensable to convert a dynamic environmental energy input into a stable power source.

This presentation reviews principles of energy harvesting and practices for small scale energy harvesters and self-powered wireless sensor modules developed recently.

Industry trends and possible research issues for further developments are discussed in order to give a technical insight into energy harvesting techniques and their applications.

While sensors often depend on batteries, energy harvesting of alternative energy sources such as solar energy may provide some alternatives, at a minimum providing support during the battery changing time.

However, energy harvesters that are currently available are expensive, and companies are hesitant to make that investment given the unreliability associated with the supply of alternative power.

CONCLUSION

REFERENCES

http://iot.ieee.org/newsletter/november-2015/powering-iot-devices-technologies-and-opportunities.html

https://www.technologyreview.com/s/517811/a-material-that-could-make-solar-power-dirt-cheap/