The U.K.’s power grid is facing the greatest pressure in its history to meet rising energy demand and achieve net-zero carbon emissions by 2050. National Grid Electricity Distribution (NGED), along with Space Solar, is working together to create a large-scale pilot project to test whether high-powered radio-frequency waves (wireless power transmission) can move electricity through the power grid differently than we do today.
This is a timely effort because the U.K.’s existing power grid infrastructure is struggling to adapt to the expected demand over the next 30 years, driven by an anticipated doubling of electricity demand. To help meet the U.K.’s commitment to generate significant amounts of renewable energy, including primarily offshore wind farms and new nuclear facilities, the Government must invest heavily in developing new renewable energy sources. However, connecting these new renewable energy sources to the existing electrical grid is proving to be difficult at best; the bottleneck in connecting the new sources of renewable energy is slowing down the shift away from fossil fuels.
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The current electrical grid was developed using physical conductors such as copper and aluminum wires that were placed in towers or buried underground. While this method of moving electricity has been effective and reliable for nearly a century, there are many significant limitations to using physical conductors to transport electricity. One major limitation is the time required to plan and build new transmission lines. This process includes obtaining necessary permits and conducting environmental assessments which can add years to the completion date of a new transmission line. Additionally, building out the infrastructure to connect remote communities to the electrical grid can be very expensive.
One promising solution to the problems associated with the use of physical conductors is the use of wireless power transmission. Wireless power transmission works by using electromagnetic waves to transport energy through free space. Similar to how radio stations broadcast signals through the airwaves, but with much higher power levels, wireless power transmission can potentially allow for a new way to distribute electricity.
Sam Adlen, co-founder and CEO of Space Solar, notes that the advancements in wireless power transmission may hold the key to supporting the growth of the world’s electrical infrastructure by referencing the telecommunications revolution that took place when wireless communication technologies became available: “We have all seen the revolution that wireless technology enabled with communications. As the demand for energy grows, the advances in wireless power transmission provide us with tremendous opportunities to support the growth of our electrical infrastructure.”
How Wireless Power Transmission Works
The use of Wireless Power Transmission (WPT), as you know, is based upon the principles of Electromagnetic Field Theory, which is a topic discussed in detail by engineering students in their Electromagnetics courses. The basis of this technology is to convert electrical energy to electromagnetic waves, send those waves through space, and then convert them back into electrical energy at the receiving end.
The underlying principle of WPT is based upon Maxwell’s Equations, which provide a mathematical description of how electric and magnetic fields propagate through space. An AC current flowing through a transmitting antenna will create oscillating electric and magnetic fields that will radiate outward from the antenna as electromagnetic waves. The amount of energy carried by the electromagnetic wave is proportional to the square of the amplitude of the electric field of the wave; a relationship that is described by the Poynting Vector, which students learn about in Advanced Electromagnetics.
Typically, power transmission engineers operate in the microwave frequency range of 2.4 to 5.8 GHz. The reason for this is because this range provides a good compromise between efficient transmission of the signal through the atmosphere and the physical limitations of the antenna size required. A lower frequency would require an unreasonably large antenna, while a higher frequency would experience more loss in the atmosphere due to rain or fog.
The transmitting system uses a phased array antenna. Essentially, this means that hundreds or thousands of small antennas work together to produce a focused electromagnetic energy beam directed towards the receiver. By accurately adjusting the phase of the signals fed into each of the antenna elements, engineers can control where the electromagnetic energy goes and how tightly it is focused. This technique is known as Beamforming, and although it is similar to the one used in 5G cellular networks, it is done at much higher power levels and therefore has the potential to maximize transmission efficiency and minimize wasted energy.
On the receiving end, the electromagnetic waves received by the receiver are captured by a Rectenna Array (Rectifying Antenna Array). Each rectenna element includes a rectifying circuit coupled to an antenna, usually consisting of Schottky Diodes, which have very fast switching times and very low forward voltage drops. The rectifying circuit is responsible for converting the high-frequency alternating current induced in the antenna to a direct current, which can then be converted back to a grid-frequency alternating current.
However, the engineering challenges associated with developing practical WPT systems are significant. To maintain alignment between the transmitting and receiving beams requires complex tracking systems, especially when either the transmitter or receiver move due to wind or structural settling. In addition to ensuring beam alignment, engineers must also limit the intensity of the electromagnetic radiation within the beam so that no animals, including birds, flying through the beam exceed acceptable exposure limits. Exposure limits for the general public are set by the International Commission on Non-Ionizing Radiation Protection at 10 W/m^2. Therefore, maintaining such low power densities within the beam, while keeping the area outside the beam free of radiation, requires close attention to beam shaping and the establishment of exclusion zones.
Finally, there is the issue of efficiency. Laboratory demonstrations of WPT have shown that efficiencies of greater than 50% from DC-to-DC can be obtained over relatively short distances. However, as the distance and power level increase to be able to supply power to a utility grid, other sources of loss are introduced. These include, but are not limited to, absorption of the electromagnetic radiation by the atmosphere, “spill-over” of the beam, and inefficiencies associated with the conversion of the electromagnetic radiation to electrical energy at both the transmitting and receiving ends. All components of the system, from the power amplifier(s) powering the transmit array to the impedance matching network(s) in the rectennas, need to be optimized in order to obtain economical efficiency levels.
Wireless power transmission project funded by Ofgem's Strategic Innovation Fund is to be a methodical assessment of how this technology may interface with existing grid infrastructure. In contrast to a full replacement of the entire transmission network, wireless links are able to fill certain roles where the use of traditional infrastructure has proven too costly or difficult to install.
The most obvious application of this technology is remote communities. Many island and mountainous communities utilize long submarine cables or overhead lines crossing difficult terrain. A wireless link would allow for an added layer of redundancy and reliability to an area without the environmental impacts associated with additional physical infrastructure. Portable wireless transmission equipment could also rapidly restore power to an area when there has been damage to conventional lines resulting from a storm or some other disaster.
NGED Director of Strategy & Transformation, Tim Polack emphasizes the numerous advantages of such innovative technology: "Thinking innovatively is essential in enabling our transition to a greener energy future; and the Wireless Power Transmission project will look at how cutting-edge technology could revolutionize the electricity network to provide a resilient, cost effective and connected solution to customers."
This technology could help alleviate the current bottleneck of connecting renewable energy generation to the grid. Wind and solar farms frequently experience extended waiting periods before being granted a grid connection because of the time it takes to construct new transmission lines. Temporary wireless links could enable wind and solar farms to become operational prior to the completion of the permanent infrastructure thereby increasing the rate at which clean energy generation is deployed.
Ultimately the success of this technology depends upon its economic feasibility. If the cost of transmitting power wirelessly is less than the cost of transmitting power through existing physical infrastructure (including costs of installation, operation and energy loss), then wireless transmission could result in lower electric bills for consumers. Additionally, the fact that no physical infrastructure is required would eliminate aesthetic concerns regarding the visibility of the infrastructure and may assist in obtaining planning permission for new connections.
Designers and engineers must develop safe and compliant regulatory frameworks for the technology. Because wireless transmission involves sending high levels of power through free space, there are several concerns regarding the electromagnetic exposure to humans, aviation safety, and potential interference with existing radio services. Designers and engineers must develop safe systems that meet the same rigorous safety standards as do their counterparts working with traditional wired infrastructure but at a lower overall cost.
Space Solar and NGED are collaborating to bring together the expertise related to the terrestrial electrical grid with the expertise of advanced wireless power transmission technologies developed for space-based applications. Space-based solar power systems face much greater challenges in terms of transmitting large amounts of power (in excess of 1 GW) from a geostationary orbit down to the Earth’s surface. Therefore, the technologies and regulatory frameworks developed for space-based solar power systems are expected to directly apply to terrestrial applications.
Successful implementation of the Wireless Power Transmission project would likely make the United Kingdom a world leader in developing next-generation grid technologies. As part of the Energy Networks Innovation Taskforce, commissioned by Ofgem and Innovate UK in October 2025, wireless power transmission was recognized as a strategic opportunity for enhancing the electrical grid. In addition, the funding provided by Ofgem through the Strategic Innovation Fund clearly demonstrates the government’s commitment to evaluating alternative methods of providing electrical grid service.
There is still considerable work necessary to demonstrate that the technology works successfully under real-world conditions in the UK, can be integrated into an existing electrical grid control system, meets all applicable safety and regulatory standards, etc. However, if successful, wireless power transmission could provide the flexibility and ability to quickly deploy the amount of renewable energy generation necessary to meet the anticipated growth in renewable energy generation over the next few decades.
TLDR
- National Grid partners with Space Solar to test wireless power transmission using high-powered radio waves instead of traditional cables
- Technology aims to address UK grid infrastructure challenges as electricity demand doubles by 2050
- Wireless transmission uses electromagnetic waves at microwave frequencies (2.4-5.8 GHz) with phased array antennas and rectenna receivers
- Key applications include remote communities, emergency power restoration, and faster renewable energy connections
- Project funded through Ofgem’s Strategic Innovation Fund explores grid integration, safety, and economic viability
- Could accelerate renewable energy deployment while reducing visual impact and planning delays
- Technology builds on space-based solar power expertise for terrestrial grid applications
