Episode Summary:
5G is the enabling technology for a new generation of smart phones and IoT connected devices, promising low latency, high-bandwidth communications. The commercial potential for the technology is massive, and as it rolls out in the US, an unexpected consequence of 5G has emerged: interference with aircraft radar altimeters. Radar altimeters are safety critical, basic flight instruments for commercial airliners, and the use reflected beams of radiofrequency radiation there similar to the signals emitted by wireless service providers. 5G towers operating the vicinity of airports could jam radar altimeters signals during final approach to a runway, which in low visibility conditions could be safety critical. The FAA is scrambling to certify which radar altimeter models and aircraft are safe for use in 5G environments, but not all airplanes have yet been approved, and regional jets are still under study.
Small modular reactors represent the new wave of nuclear fission technology which promises to deliver clean, carbon free power at low cost. Compared to traditional light and heavy water reactor designs, SMRs are designed to operate without large containment structures or the complex and layered safety systems necessary for traditional reactors. Hyundai Engineering has taken a $30 million equity stake in Seattle-based Ultra Safe Nuclear Corporation, were building a test reactor to demonstrate the company’s novel single pass uranium fuel cycle. Using encapsulated TRISO fuel, the design will deliver 5 MW-e in HR transportable form factor that can be deployed almost anywhere. The reactors pre-fuels at the factory and is simply replaced after 20 years of operation. The high-temperature gas cooled design requires minimal human monitoring and shows interesting possibilities for process and space heating applications as well as thermal power generation. The test unit is scheduled to go online in 2026 at Chalk River in Ontario, Canada.
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Transcript of this week's show:
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Segment 1: It’s not very often that a new type of communications technology creates safety issues in a completely unrelated industry, but this week the US Federal Aviation Administration imposed restrictions on flight operations using some types of aircraft radar altimeters that are close to 5G mobile service areas.
5G, the current state-of-the-art in wireless technology, operates in C band radio frequencies, and commercial aircraft operators, airports and global aviation authorities are concerned that 5G radiation may interfere with the operation of aircraft altimeters during safety critical flight operations, especially during approach and landing in poor visibility. US 5G services launched widely on January 19, and as of date 78% of the US commercial aircraft fleet carried altimeters approved for low visibility approaches in 5G deployment areas. The remaining will operate with restrictions on low or zero visibility landings. The FAA has published a list of airports with potential interference issues, and it includes major hubs such as New York and Chicago. as well as airports in St. Louis, Houston, Detroit, Cleveland and Cincinnati.
To mitigate the highly disruptive effects of nationwide flight cancellations into airports where weather is a significant factor, the agency has aggregated 5G transmitter location and power level information from wireless companies and shared this data with the avionics industry. A limited workaround has been developed to use some GPS guided approaches at some airports, and as developed a process called the Alternative Method of Compliance (AMOC) for airlines to test their altimeters for reliability in a noisy 5G environment.
5G is not new, and other nations such as Japan and France have already rolled out significant 5G services without disruption to their aviation sectors. In France for example, 5G signal strength is 2.5 times lower than in the US, and 5G safety buffer zones around airports are restricted to interference over the last 96 seconds of final approach, compared to 20 seconds in the US. France requires that 5G antennas angled downward to minimize interference. Mitigation efforts in the US are expected to be similar at least in the short term, while the FAA approves avionics and test procedures to clear more aircraft types.
Most Airbus and Boeing aircraft are already cleared, with one notable exception at press time: Boeing’s flagship, the 787 Dreamliner. Regional jets, the backbone of the increasingly point-to-point system used today, are still under study by the FAA. It’s unknown how long it will take before all current equipment is approved for low visibility landings, but the telecom industry is cooperating the short-term with reduced power levels around airports. We’ll report back when the FAA announces a definitive solution.
Segment 2: CO2 reduction targets set by the Paris Accords is injected new life into technology that was once declining: nuclear fission. While conventional light water and pressurized heavy water reactors have been run successfully for over half a century, capital costs are very high both through the scale of your power pet projects and the need for complex engineering to ensure safety.
A new generation of small modular reactors offer hope for more favourable economics with enhanced safety, and South Korea based Hyundai Engineering has announced a $30 million equity stake in Seattle-based Ultra Safe Nuclear Corporation to develop and commercialize USNC’s novel reactor design. Ultra Safe as developed a high-temperature gas cooled reactor using a graphite moderator and a single pass uranium fuel cycle.
The company claims coolant outlet temperatures of up to 750 C, allowing practical use for tasks other than thermal electricity generation including process heat and hydrogen production through a thermochemical sulfer-iodine cycle. The key enabling technology for the reactor design is in the fuel. Ultra Safe’s design uses tri-structural isotropic or TRISO fuels, which encapsulate small pellets of fissionable material in layers of graphite and silicon carbide.
Encapsulation of the fuel not only eliminates the safety risks of fire or chemical reactions, but it allows Ultra Safe to preload fuel into a reactor core during factory assembly, with no need for on-site refuelling for the life of the reactor. Encapsulated fuel and careful reactor geometry makes the system intrinsically safe, greatly reducing overall system cost through the elimination of control rods and their associated actuators, for backup’s grams systems that poison the reactor.
In Canada, the provincial electricity generator Ontario Power Generation is entered into a joint venture with the company to install a 5 Mw-e reactor at a test site in Chalk River, Ontario the centre of Canadian nuclear research. OPG plans to use the technology for electricity generation, although the systems transportability and lack of reliance on a large body of water for cooling makes it practical for processor space heating applications in remote areas of the country as well.
If it proves cost-effective, the future of nuclear may be as much about heat as it is about power.