Achieving cost-effectiveness in power transmission has been a major challenge to the global energy and utilities industry. In several regions where the generation cost could be minimized with induction of renewable resources, the levelized cost of energy (LCOE) increases due to the high cost of transmission. To address this, New Zealand based Emrod has developed a technology, which can deliver long-range, high-power, wireless power transmission (WPT) which can potentially replace the existing copper line infrastructure for transmission and distribution. The technology, if commercialized, can be lucrative for utilities across a number of regions globally, such as China and several countries in Europe, which have identified the right mix of energy generating resources to optimize the LCOE offered to the end users.
Emrod’s march as an anti-copper firebrand: The Emrod technology leverages electromagnetic waves to safely and efficiently transmit energy wirelessly over significant distances. The technology is presently in the prototype stage, which would need to undergo considerable modifications to be scaled up. However, the prototype was successful in securing some public funding in New Zealand. The Emrod team designed and built the protype in Auckland in collaboration with Callaghan Innovation, an innovation agency driven by the New Zealand government. Emrod has been working with Powerco, New Zealand’s second-largest power distributor, which has expressed interest in deploying a proof of concept of the technology. The exercise would be directed towards finding the level of compatibility of the technology with the existing distribution circuit operated by the utility.
Following stringent safety measures: Emrod leveraged a non-ionizing Industrial, Scientific and Medical frequency (ISM) band to execute the transmission in order to maintain high safety standards to be used around humans and animals. Furthermore, the technology has been equipped with a “low power laser safety curtain” which shuts down power transmission before any object, such as a bird or a drone can touch the main beam. The system also allows placing a meter anywhere to measure the usage of electricity.
High cost can stonewall adoption: The technology, once commercialized, would be appropriate for transmitting energy to remote locations with limited or no access to the grid. A full scale deployment would involve a one-time but a significant cost of several equipment including transmitting antennas, an array of relays and a receiving rectennas (i.e. a rectifying antenna which can convert microwave energy into electricity). Thus, the existing distribution grid infrastructure would remain unchanged. The transformers used in stepping down the transmission voltage (usually 110 KV) for directing it to the distribution grid would thus, be fed with the electricity converted directly from microwaves. A conventional rectenna can convert radio waves with low frequencies i.e. high wavelength to electricity. A sophisticated rectenna would thus, be required to obtain the necessary frequency, implying fabrication challenges. Also, the utility should have a series of such rectennas spread across the transmission path (typically, a couple of kilometers) which can bring down the financial viability of the technology.
Key Takeaway: The technology would be useful in case of unplanned outage events i.e., a truck equipped with a rectenna, driven to a visual range of a relay can establish a temporary wireless power connection. However, there are few segments of end-users who would not be influenced by the adoption of wireless power transmission. The zero-power home (where the house generates its own energy consumption and feeds the excess to the grid for monetary benefit) owners, for example, would require a very robust distribution network and would hardly be impacted by any change or disruption in the transmission lines. Also, end-users such as hospitals or military bases, which require high reliability in power supply are expected to continue with the traditional supplies, reinforced by appropriate energy storage systems as back-ups. The technology may replace small captive power plants for residential units in the years to come. Also, the technology promises potential for electric vehicle applications such as charging spots on highways.
Overall, the understanding of long-distance power transmission could be myopic. While the technology can obliterate the copper-based transmission, there are also associated costs to get the new technology aligned and integrated with the generation and distribution infrastructure. These ecosystems are quite hardwired into the overall power economy and thus, difficult to remove or replace. Thus, identifying key use cases would the key to profitability for any utility adopting this technology.
References:
New Atlas: New Zealand’s wireless power transmission: Your questions answered by Loz Blain, accessed 31 Oct 2020, accessible at https://newatlas.com/energy/long-range-wireless-power-transmission-new-zealand-emrod/
Medium: The dream of Wireless power transmission might soon become a reality, by Faisal Khan, accessed 31 Oct 2020, accessible at https://medium.com/technicity/the-dream-of-wireless-power-transmission-might-soon-become-a-reality-9b57f4bf7c57.
Authors
Avimanyu Basu
Lead Analyst with Information Services Group (ISG)
