In August 2017, Lavender Pond Farm, New England’s largest lavender farm located in Killingworth, CT, announced the installation of a solar SmartFlower, the first all-in-one, plug and play PV solar system.
Inspired by sunflowers and other phototropic plants that follow the sun across the horizon, the SmartFlower wakes up at sunrise, fans out its twelve solar “petals” to 194 square feet, and automatically cleans itself in preparation for capturing the sun’s rays. SmartFlower then turns to face the sun at a 90° angle and follows the sun throughout the day using dual-axis tracking to maximise solar energy yield. At night, the system automatically folds itself up for compact storage, then starts its professional cycle over the next morning. One SmartFlower produces the equivalent of a 4 kW rooftop system, thanks to these Sunbots, which give an aesthetically pleasing appearance to the solar industry.
In July 2022, Samsung released a television remote control that doesn’t require batteries as it draws power by harvesting otherwise wasted energy emitted by Wi-Fi routers. This new version includes a tiny antenna that can capture Wi-Fi signals from a distance of up to 40 meters, allowing it to charge even in dark rooms.
A pasta-shaped robot with no motors, batteries, or computers can roll over a range of surfaces and cross its pathway by harvesting heat energy and turning it into motion.
Don’t you hate it or feel sad when your phone battery dies? In the future, your cell phones will be able to recharge by graphene generators that harvest electricity from moisture in the air and your breath.
A wristband containing a thermoelectric generator can convert body heat into enough electricity to power it. In the future, the technology may be able to power smartwatches.
Blue-green algae, a type of cyanobacteria sealed within a container and placed on a windowsill, can power a computer continuously for six months by photosynthesis.
All of the above-stated examples undoubtedly give us a wonderful world of energy harvesting. Energy harvesting (also known as power harvesting or energy scavenging) is the process in which energy is captured from the environment and converted into usable electric power.
Power consumption and IoT network elements
Nowadays, scientists are much concerned with the power consumed by various engineering items. As we all know, the demand for power increases as the population grows, and technology advances. The peak power demand rose to 209.66 GW per day in February 2023. A 50″ smart TV consumes 50-60 Watts per hour, while a 50″ LCD TV consumes 70-80 Watts per hour. So, the power-driven world is quite frightful.
Now let us look into the power consumed by various elements of the IoT network.
| System | Component | Power consumption |
Wireless technology | Wi-Fi | 0.192kwh/day |
| Zigbee node | 36.9mW | |
| MiMax node | 75W (43″ Ultra HD Tv ) | |
| Bluetooth | 1W | |
| BLE | 0.01-0.5W | |
| Cellular | 0.1- 0.5 W | |
| LoRa | 100mW | |
Sensor devices | Temperature/ Humidity | 0.2-1 mA |
| IR | 20mA even during idle state | |
| Ultrasonic | 4-20 mA | |
| PIR | 65mA | |
| Light | O.65 micron A | |
| Camera | 270-585mA | |
IoT node/gateway | WASP mode | 9mA |
| Pi | 100-500mA | |
| Xbow | 17.5-19.7 mA | |
| Arduino | 3.87-13.92mA |
Different Energy Harvesting Methods
Piezoelectric, thermoelectric, electromagnetic, and photovoltaic techniques are some of the energy harvesting technologies available today.
Energy Harvesting Roads
Surprisingly, roads can nowadays charge EV vehicles as they move along it. The idea that a road can collect and harvest energy from the vibrations of passing cars, buses, and trucks existed only in science fiction. But now it is a reality!
Take Israel, for example. ElectReon, a startup firm from this country, is developing an in-road inductive charging system. Its charging solution powers EVs from electrical fields generated by copper coils under the asphalt. Receivers are installed at the vehicle bottom to transmit the energy directly to the battery while driving.
Elonroad, a firm from Sweden, has developed charging infrastructures for all EVs. These can be employed in cities, highways, parking spaces, and taxi lines.
Electric highways and India
Around 1.17 million EVs were sold in FY 2022-23, making up over 50% of the 2.27 million EVs on Indian roads. EVs are expected to draw 120 GW to 332 GW by 2030, accounting for the majority of the load on India’s power grid. As such, energy harvesting technologies are becoming prominent for Indian roads.
The Delhi-Jaipur highway is expected to be EV charging-ready and operational for the public by the end of this year. India is aiming to develop a smart E-highways network of 5,000 km by 2024.
Three Different Methods Likely to Be Employed in India to charge running EVs along electric highways
To charge running EVs along electric highways, three different methods are likely to be employed in India:
1. The pantographic model: A contact arm is attached to the top of the freight or electric vehicles. The arm gets connected to an overhead cable that is electrically charged along the stretch of the highway.
2. The conduction method: The contact arm for the motor vehicle is at the bottom and connects to the road to be charged. In the conduction method, the road is required to have an electromagnetic current.
3. The induction model: There is no contact arm, and the vehicle is charged wirelessly through an electromagnetic technology that has to be installed on both the roads and the vehicle.
At present, the lithium batteries driven world is impressive, but the disposal of such batteries at the end of their usable life is becoming more and more problematic. Energy harvesting is undoubtedly peculiar and offers the dream of perpetuity.
The author served as a lecturer in three different polytechnics for 10 years and is also a freelance writer and cartoonist.
