Energy Harvesting Mechanisms in a Smart City—A Review

Abstract

The issue of how to power the deployed Internet of Things (IoT) nodes with ubiquitous and long lasting energy in order to ensure uninterruptible optimisation of smart cities is of utmost concern. This among other challenges has continued to gear efforts toward energy harvesting research. With the outbreak of COVID-19 pandemic and the lockdown that nearly paralysed activities of everyday living in many nations of the world, option of human remote interaction to enforce social distancing became imperative. Hence, the world is witnessing a renewed awareness of the importance of IoT devices, as integral components of smart city, especially for the essence of survival in the face of lockdown. Energy harvesting is a possible solution that could enable IoT nodes to scavenge self-sustaining energy from environmental ambient sources. In this paper, we have reviewed most sources within city that energy could be harvested from, as reported by researchers in literature. In addition, we have submitted that energy sources can be application specific, such that, since there are many free sources in the city as presented in this review, energy should be scavenged within close proximity of need for various IoT devices or wireless sensor networks (WSNs), for smart city automation.

IoT-Enabled Smart Cities: A Review of Concepts, Frameworks and Key Technologies

“…Smart energy systems involve the intelligent integration of decentralized renewable and sustainable energy sources and their efficient distribution [91] and aim to optimize power consumption [92]. Smart grids take advantage of ICT and IoT technologies for the better management of power generation and distribution, exploiting, for instance, prediction models (developed from collected consumption data) and often ensuring the self-healing of the energy network supply [93].…”

“…Big data collection and analysis in healthcare contexts can be useful for monitoring critical cases, conditions and events [109], especially in the period of COVID-19 pandemic; • Quality Education: Smart education solutions contribute to creating innovative education services, as well as to enhancing the interaction between remote and real-world learning activities [66]; • Clean Water and Sanitation: Smart water solutions [100] are employed to monitor the quantity and quality of water distribution and aim to minimize consumption and manage wastewater treatments [101]. This represents an important step in the proper design and maintenance of quality water systems; • Affordable and Clean Energy: Smart energy solutions and energy grids [3,58,93,96,97] contribute to a more efficient energy distribution and usage [92], helping to minimize power consumption and consider innovative sustainable energy sources [91]; • Decent Work and Economic Growth: Smart governance solutions [3,38,39,[46][47][48][49][50][51][52][53][54] contribute to economic growth [38] since they are expected to provoke a strong push in the direction of smart and digital public administrations [39]. Moreover, smart economy solutions [83,84] can also contribute to allowing citizens, companies and smart city stakeholders to follow the market for smart applications and data economy, rethinking the flexibility of jobs and labors [84] and, thus, redefining the economic value associated with them; • Industry, Innovation and Infrastructure: Smart industry solutions [3,14,33,90] are establishing new and relevant digital infrastructures for sustainable industrial production [88]...…”

From Macro to Micro: Impact of Smart Turbine Energy Harvesters (STEH), on Environmental Sustainability and Smart City Automation

“…The device for STEH in this study is usually used to prevent birds from entering into the chimney, and it is available on most roof-tops of Portuguese homes. In [21], it is stated that there is a desire to harness energy from every available ambient energy in the environment and in close proximity to the load nodes. Hence, the interest in converting a chimney device to a table top Smart turbine of 18 vertical blades [38], is born out of the fact that ambient energy is wasting away from the continuous aerodynamic activity of this device which is constantly spinning without connecting any active device.…”

“…Meanwhile, the cost of establishing a macro or mini grid in order to scale (or step) down to the very small amount of energy required by these devices; which is usually micro-watts or milli-watts; the man power required; and the time consumed in achieving a scale down from generation through transmission; to distribution to the applicable load centres of IoT nodes, are not a good Return on Investment (RI). This is in comparison with the situations when the energy required to support these devices are in close proximity to, or embedded in the devices by means of energy harvesting techniques [21]. Hence, this study presents the use of smart turbine energy harvesters (STEH), as ideal 'Turbine Harvesters' to supply Internet of Things devices, and their importance as renewable sources of energy considering their ecological and environmental friendliness with respect to their capability for sustainability.…”

“…However, it has a social economic advantage in that several unit of this model can be deployed in the smart city at different locations at the same time with individual IoT nodes, hence hundreds of team players could be engaged in fabricating this same model at the same time within the smart city. Meanwhile, the choice of dynamo attached to STEH; which is as essential part of the set-up because turbines are not stand-alone harvesters [21], can pose a serious disadvantage if not carefully selected. This was evident in the initial choice of bicycle dynamo which was too weighty for the turbine to spin.…”