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It’s disheartening how much power gets generated and then promptly lost as it travels through grid networks. This leaking of electricity happens when it vanishes as heat as well as when it is pilfered by thieves and nonpaying customers. More than half of the countries that track these metrics lost at least 10 percent of their electricity in 2023, according to the World Bank. Losses topped 20 percent for 24 of those nations. Two countries lost more than half of what they generated. With numbers this high, cutting down on losses makes sense. Electricity demand is rising beyond what many grid operators can supply; reducing waste would help meet some of that demand without having to build new power plants. Plus, when the power comes from fossil fuels, any loss means emitting even more greenhouse gases into the atmosphere. And electric losses hit the bottom lines of power providers, which ultimately pass those costs on to everyone else. The trouble is, reducing electricity losses is a hard and expensive process that takes a long time. Typically, the less maintained the grid infrastructure, the more electricity that’s lost. And the more fragile the region’s law enforcement and government, the more prevalent the power theft. Natural disasters and war make things worse. Delhi’s Power Grid Comeback Fixing a power grid requires a systemic approach across many sectors. There’s no one technology that will solve the problem. At the outset, the obstacles to success may feel insurmountable. Equipment across entire grid networks must be updated. Multiple arms of government must agree to reforms and coordinate to ensure power providers are set up to succeed. Regulations must be written or revised, investments made, cultures changed. The city of Delhi did all those things. Over the past 25 years, it cut its electricity losses from about 50 to 5 percent. How the city pulled off that impressive feat is the focus of “The Epic Comeback of Delhi’s Power Grid” by Mini Shaji Thomas, an electrical engineer at the university Jamia Millia Islamia who has lived in Delhi since the 1990s. She gives us a view from the inside—as a resident and a power systems expert. Delhi is a shining example, but some other regions have significantly lowered electricity losses over the last quarter century too. The country of Georgia went from losses of over 16 percent in 2002 to about 8 percent in 2023. In Singapore, losses dropped from 6.6 percent to a nearly nonexistent 0.2 percent over the same time period. Global Electricity Theft Crisis But there are many parts of the world where electricity losses remain a problem or have gotten worse. In Jamaica, where power theft is rampant, losses have hovered between 21 and 28 percent for years. Argentina’s losses nearly doubled between 2015 and 2023, going from an all-time low of about 12 percent to an all-time high of nearly 24 percent. The main problem: Transmission and distribution companies lacked the capital to maintain and upgrade their networks, which left equipment operating under stress. A delay in the installation of smart meters has allowed thieves to more easily siphon power and tamper with meters. Thomas says she hopes her account of Delhi’s grid comeback will serve as a blueprint for others. It’s possible to replicate the sweeping changes Delhi made, she says. But it “requires a concerted effort from all stakeholders, customers, the utility, the government, and their employees.”
If you own an at-home server, a gaming computer, or just a laptop that doesn’t get much love, listen up. You can now put that spare computing power to use and earn some passive income in the process. AI companies are hungry for more compute to run AI inference—the process of using a pre-trained model to respond to queries—and they’re willing to pay you for it. “Imagine Uber or Airbnb, but for AI inference computing tasks,” says Ilman Shazhaev, founder and CEO of Far Labs, based in Abu Dhabi. The AI boom has spurred on construction of massive data centers, often damaging local communities by raising electricity prices, straining local water resources, causing environmental damage and noise, and being just plain ugly. Huge data centers are likely not going anywhere—training new frontier models and running AI models from leading companies will likely still be the purview of these behemoths. But now, several companies are providing AI inference on smaller, mostly open-source models. They are running inference on pre-existing computing power spread throughout homes and small businesses, and compensating owners. “Everyone thinks the only way to do it is data centers. And data centers are extractive for the communities in which they’re built, and they don’t return services or taxes or much of anything to the people there. So why not just turn this whole thing on its head?” says John Federico, founder and CEO of Evolving Edge, in Austin, Texas. “The compute power is out there. If you can orchestrate it, then you’re actually adding value to those communities directly.” The idea isn’t entirely new: From 1999 to 2020, a volunteer-based project called SETI@Home used spare computers to search for signs of extraterrestrial life in radio telescope data, for instance. But now, commercial companies are eager to use the same strategy. Shazhaev’s Far Labs is launching its platform Far AI in the coming weeks, while Federico’s Evolving Edge is currently in open beta. Other companies, like Bless Network, Salad, and Gradient have started to provide similar platforms over the last year. Connecting to the network Federico has been a computer hobbyist since youth, and he has amassed a whole server in his basement to run his projects. “It just hit me one day, there’s all this talk about not having enough compute, and I just thought, well, 92 percent of the country has broadband, and you have people like me who have mini data centers in a closet,” he says. Federico sees the potential hosts as people much like himself who have already invested in home servers, and he aims to make the process of selling spare compute as seamless for them as possible. “Sign up for the program, install an application,” Federico says. “All we want to do is run jobs on your machine when you tell us we’re allowed to. The only thing we do is monitor the resource usage. And of course, you can give us a schedule.” With a large enough network of devices, the platform would have compute available whenever it’s needed. Privacy and security are primary concerns for such hosts. To reassure the users that their local data is secure, and that no malware will be downloaded to their devices, the team open-sourced their scheduling software. “The node software is open source, so anyone can look at it, see what it does. All we want to do is run jobs on your machine when you tell us we’re allowed to,” Federico says. Far Labs’ Shazhaev explains that the company’s software is designed around a principle known as “least privilege”: granting both the host and the user the least access possible to accomplish the task. Inference runs as an isolated workload with authenticated, encrypted communication and explicit limits on the GPU, CPU, memory, storage, and network resources it may use. Customers do not receive arbitrary access to the host machine, and providers can inspect resource use, pause the node, revoke access, and remove the software at any time. The protection also works in the other direction. Workloads are segmented and only the minimum required information is exposed to an individual node. Sensitive enterprise workloads can be restricted to controlled hardware rather than routed through consumer devices. Divide and conquer Massive data centers still have advantages from the user perspective: top of the line GPUs and CPUs, high speed networking, thick cables, and sophisticated cooling. User devices are usually less powerful, more varied, and less reliably connected to one another. “This is quite a difficult issue from the science angle,” Shazhaev says. “You want to do a similar level of tasks that are happening in those high infrastructure data centers, and run them on the user device with limited capacity.” Evolving Edge’s Federico says this is an issue for the largest, state-of-the art AI models. But those are not always needed and are often not even preferred. “There are numerous companies, once they reach a certain scale, suddenly paying for tokens on a state-of-the-art frontier model [that] no longer makes sense for their needs,” he says. “Instead, they are fine-tuning open-source models for specific tasks that they have in their business. These models don’t require anywhere near the resources that some of the state-of-the-art models do. It’s just using the right tool for the job.” Smaller, open-source models can often fit on a single user device. But if that fails, there are tools to split a single inference task over multiple GPUs or CPUs. Evolving Edge is using an open-source tool called Ray to perform this splitting, while Far Labs has developed its own proprietary software that not only splits the workload, but wraps the splitting in a layer of security and reliability-providing software. “One thing we have done is we shared the model,” Shazhaev says. “We take the model, we cut it into many pieces, then these pieces will be distributed through different devices. And we have an orchestrator and a load balancer which manage the task flow, so each device processes a part of the task. Then we combine the answers in the main brain, the orchestrator.” Through a combination of using smaller, more task-specific models, and splitting larger models between disparate devices, the teams claim they can perform inference much cheaper than a traditional data center “because we don’t have capital expenditure,” Shazhaev says. Gaming PCs are a common source of spare computational power in the home. Dizzaract The distributed advantage Not only is it cheaper to run inference this way, it is also more reliable, Shazhaev claims. The companies have access to a distributed network of computing resources, rather than one giant device that can experience outages. Shazhaev compares this to cryptocurrencies, and their resilience through decentralization. “Today, to shut down Bitcoin, you need to nuke the whole planet. Here, we have the same concept,” Shazhaev says. Federico explains that this resiliency would be beneficial not just for AI inference, but for all kinds of applications, including smart cities, environmental sensors, autonomous vehicles, and more. During an Amazon Web Services outage in 2026, for example, smart beds were stuck in their upright positions and their users couldn’t adjust them. Federico says that a distributed network where everything doesn’t need to be routed through a single data center, say, in Ashburn, Va., would make those kinds of outages much less impactful. “We could lose 100 nodes in a network of 250,000 and it wouldn’t matter,” he says. If the network of user devices is substantial enough, every job can be routed to a nearby device, decreasing the latency. Far Labs claims a latency of 100 milliseconds or less on its platform. The lower cost and lower latency of this approach may even enable new use cases, such as in-game AI video generation, which is currently prohibitively slow and expensive. “OpenAI last year had $30 billion in revenue, but they closed the financial year at an $8 billion loss. Why? The official reason is due to the high cost of inference,” Shazhaev says. “And those are mostly text models. For gameplay, you have audio, video, animations: It’s heavy data, and you need real-time responses. So, we’ve been trying to solve this issue.” All of these companies are trying to tap into an untapped resource of local compute, and hoping it’ll benefit the device hosts and users alike. “All these big guys are running around building data centers,” Shazhaev says, “but I believe there is enough compute power that already exists in the world.”
When I started at Spectrum 25 years ago, a senior editor suggested that I find a “rabbi,” by which he meant someone who could mentor me in how EEs approach problems and evaluate potential solutions. I didn’t find one right away. Then in 2005 we decided to do a special report, focusing on the challenges of enterprise software development. I suggested we invite IEEE Life Senior Member Robert N. Charette, a self-described risk ecologist, prolific book author, and leading authority on risk management and software engineering, to explore in our pages the myriad reasons software projects fail. His seminal article “Why Software Fails” is still read in university engineering classes today. IEEE Life Senior Member Robert N. Charette is one of IEEE Spectrum’s most prolific authors.Robert N. Charette It was, as they say, the beginning of a beautiful friendship. I had found my rabbi, one who shared my love of writing. We settled into a rhythm that would last more than 20 years, talking on Friday mornings about a range of topics including the growing ubiquity of software in our lives. So when I became Spectrum’s website editor in 2007, he was the first contributor I tapped to start a regular blog (remember those?). The Risk Factor was born and over the course of more than 10 years and 1,750 posts, Bob chronicled hundreds of software debacles, culminating in “Lessons From a Decade of IT Failures,” which won a Jesse H. Neal Award for Best Infographics in 2016. Ironically, yet predictably, those infographics were created in a software package that is no longer supported and thus are lost to the bits of time. “I like the expression on the fish just before it’s going to be swallowed by the heron.”Robert N. Charette Bob, however, was not a one-trick pony. In between his full-time job running his two management consultancies and raising a future biochemist and a future civil engineer, his daughters Maura and Megan, he also wrote many deeply reported and insightful articles. These include last year’s “The Doctor Will See Your Electronic Health Record Now,” the eye-opening 12-part series and e-book The EV Transition Explained, and my personal favorite “Automated to Death,” about the deadly consequences of the automation paradox as manifested by the cyberphysical systems that pilot planes, trains, and automobiles. “The young bald eagle I photographed in September 2024 had bands that I could read which identified it as a female born in May 2024, near Lexington Park, St. Mary’s County, Maryland, about 65 miles away from where I live.”Robert N. Charette His main goal all along has been to make software visible, as he told me one Friday in July. “Software is all around us, but we don’t recognize it at all,” he said. “I really wanted my stories to help people better understand complex software systems. You can’t see software, you can’t touch it, you can’t taste it. You may feel the consequences of software failure, but you never see the reason itself.” When he told me that he was hanging up his hat as a contributing editor to focus on nature photography and to write a handful of fictional trilogies, including one entitled “The STEM Murders” featuring an engineer-turned-detective and his rabbi, I asked him which of his Spectrum articles had the biggest impact. “The hummingbird I caught with the yellow of a road curb behind it.”Robert N. Charette He singled out the 2013 feature “The STEM Crisis Is a Myth.” “Spectrum gave me a platform to question the assumption that we needed more STEM graduates. Until then, people didn’t really realize how much of the STEM crisis was a mythology that was perpetuated by employers and the academic community and was foisted on the IEEE community,” he said. Charette made a career of questioning assumptions. The best way to mitigate risk, he told me as our Friday chat drew to a close, is to be careful making assumptions in the first place. “My main risk maxim is assumptions made are risks accepted.”
“The lowest-cost place to put AI will be in space, and that will be true within two years, maybe three at the latest,” SpaceX founder Elon Musk told the World Economic Forum in Davos this past January, as his company was preparing to go public. Later that month, SpaceX filed an application with the Federal Communications Commission for an orbital data center constellation of up to 1 million satellites in low Earth orbit, 500 to 2,000 kilometers above Earth. And just three days before the IPO, he discussed some initial design specifications for a new AI-1 satellite data center in a video interview. Musk is prone to hyperbole when it comes to timelines. Full self-driving cars by 2017. First human mission to Mars in 2024. Ten thousand Optimus humanoid robots by the end of 2025. Et cetera. For orbital data centers, which he says will be a cost-effective alternative to terrestrial data centers within three years, the math won’t make sense for several years, if ever. Consider this: There are roughly 14,500 active satellites in orbit. Musk’s Starlink constellation accounts for about two thirds of those. Both the launch cadences and satellite-manufacturing capacity would have to scale up astronomically to deploy a million orbital data center satellites. For context, there have been roughly 7,000 orbital launches in all of human history. To loft 1 million satellites into low Earth orbit on SpaceX’s Starship, which is designed to carry up to 60 satellites per vehicle, would require 16,666 launches exclusively devoted to satellite deployments. Considering that SpaceX launched a record 165 orbital missions in 2025, even at 10 times that cadence, it would take a decade. And how long would it take to build 1 million satellites, given Starlink’s current pace of around 4,000 per year and a generous tenfold increase in capacity? Short of a manufacturing revolution, try 25 years. The reality is that the vision of massive constellations of orbital data centers is nowhere close to being realized. As this month’s cover story, “Why Orbital Data Centers Are So Hard” by Andrew Cavalier of ABI Research, makes clear, the reality is that the vision of massive constellations of orbital data centers is nowhere close to being realized. Dina Genkina, IEEE Spectrum’s computing and hardware editor, put the idea into perspective: “Starcloud (a startup that has applied to the FCC for an 88,000 orbital data center satellite constellation) sent one Nvidia H100 GPU in space so far. Their radiator was too weak to let the chip run at full power.” As Cavalier shows, cooling even a single Nvidia H100 GPU in space is difficult: It draws 700 watts, which will require 1.4 square meters of radiator at 60 °C. A 40-kilowatt rack of servers will need an 80-m² radiator; a 100-megawatt data center will require 2,500 of those radiators. Some astronomers are understandably concerned that a million satellites with giant radiative wings would blot out the stars. So if the economics doesn’t make sense, if the chips are at the mercy of the radiative ravages of space, and if humanity will lose its view of the stars, not to mention increasing the risk of triggering the Kessler syndrome, why are the hyperscalers hyping orbital data centers? Genkina offered the obvious answer: sweet, sweet moolah. “The Elon Musk part of it is honestly genius because he’s got xAI building the data centers, SpaceX sending them to space, and Tesla building solar panels,” Genkina says. “It’s almost like he’s paying himself.” Two Analyst’s Views of SpaceX’s Proposed AI1 Data Center Satellite Michael Pierce, Principal at Technology Strategy Partners Musk’s timelines are notoriously overly ambitious, but I think SpaceX’s orbital data centers might reach cost parity with terrestrial data centers in 5 to 10 years. The Starlink laser-link network already exists as the communication backbone for any SpaceX compute constellation, and that infrastructure is what no new entrant can replicate quickly. The chip-agnostic payload design probably reflects their disclosed difficulty securing AI silicon as much as any modularity philosophy. My view is that the only realistic near-term application is a SpaceX mega-constellation for inference. Training workloads likely cannot tolerate the synchronization and latency constraints of a distributed orbital system. Our report analyzed the market from the integrator’s vantage point, but AI1 is what it looks like when one player has assembled all the necessary advantages simultaneously. The question is whether the terrestrial data center industrial base will degrade or improve on economics. I don’t have insight into SpaceX’s internal costs, as opposed to public pricing, on all their components, so it’s hard to say if they’ll completely dominate or not. Even if they are not cost competitive with terrestrial data centers for another 5 to 10 years, it may simply be faster to get new compute that just happens to be in space. Matt Hasan, AI strategist and independent consultant My initial view is that AI1 does not fundamentally change the rationale for space-based data centers as much as it changes the timeline and scale. The underlying drivers remain the same: escalating AI compute demand, growing power constraints on terrestrial grids, and the desire to colocate energy generation with computation. What AI1 does signal is that the concept is beginning to move from theoretical discussion toward engineering and capital allocation decisions. The announcement adds credibility to the idea that hyperscale computing infrastructure may eventually expand beyond terrestrial constraints rather than simply competing for increasingly scarce grid capacity on Earth. That said, significant economic and technical questions remain. Launch costs, maintenance, hardware replacement cycles, thermal management, latency-sensitive workloads, and overall system economics will ultimately determine whether space-based data centers become a mainstream extension of AI infrastructure or remain a niche capability for specialized applications. The key development is not that these questions have been resolved, but that major industry players now appear willing to invest resources toward answering them.
Children born after 2013 are the first generation to grow up fully immersed in digital systems, which weren’t designed with them in mind. One‑third of the world’s Internet users are younger than 18, according to UNICEF, yet these systems shaping their daily lives were built for adults. They were optimized for engagement and designed long before people understood how profoundly digital environments influence children. For engineers and technical professionals, online safety is not an abstract policy debate. It is a design challenge that demands rigor, systems thinking, and ethical foresight. Governments around the world are also beginning to recognize the problem. Policymakers from across Australia, Brazil, the European Union, Indonesia, and the United States are responding to risks engineers have long understood: Addictive features, inappropriate content, opaque data practices, and algorithmic systems shape user behavior in ways that their creators did not fully predict. For years, technology moved faster than governance. Now governance is trying to catch up. Global Shift Toward Design Reform Supporting National Digital Ambitions In Athens this year I met with senior leaders of Greek government agencies and key national research institutions. Greece is moving quickly on digital transformation and responsible technology governance, and our discussions reinforced IEEE’s role as a trusted, neutral collaborator. We focused on supporting Greece’s ambitions in digital modernization and public‑sector innovation. We also discussed responsible AI and age-appropriate digital design in Europe and elsewhere. These engagements, grounded in shared values and long‑term commitment, strengthened IEEE’s presence within the European ecosystem and opened new pathways for collaboration on trustworthy AI and child‑focused digital well‑being. The European Union and the United Kingdom have been among the first to act, embedding age‑appropriate digital design into their broader children’s rights agenda. Drawing on IEEE expertise and global best practices, Indonesia is the first country in Asia, and Brazil is the first country in Latin America, to adopt age-appropriate design regulation. Australia is aiming to limit access to harmful content and addictive design features through age restrictions on certain platforms. And in the United States, in addition to federal efforts, states including California, New York, and Utah are enacting approaches including age-appropriate design principles. Across these efforts, a shared realization is emerging. Protecting children online is not simply about filtering content or adding parental controls. It requires rethinking the architecture of digital systems regarding how data is collected, how algorithms make decisions, how interfaces influence attention, and how AI interacts with the developing minds of young users. Engineers and technical professionals understand that design choices are never neutral. They encode values, incentives, and assumptions. When the user is a child, those choices carry greater weight. This is where IEEE’s work becomes more essential. Protecting Children Online For more than a decade, IEEE has been building technical and ethical foundations for safer digital experiences. The first IEEE standard on age-appropriate design in 2021 marked a turning point. It offers a structured, principled approach to designing with children’s rights in mind. The Institute’s 2022 article “Use a New IEEE Standard to Design a Safer Digital World for Kids” highlights how the standard helps translate those principles into engineering practice. Today the IEEE Standards Association’s (SA) Trustworthy Digital Experiences portfolio provides a practical, technically grounded framework for governments and industry. Spanning ethical design, data governance, algorithmic transparency, and child‑focused digital well‑being, it has already initiated discussions with government stakeholders around the world. This work helps bridge the gap between engineering realities and policy ambitions. No single country can solve these challenges alone. Many policymakers lack access to the combined expertise in technology, governance, and children’s rights needed to act quickly and effectively. This collaborative effort helps close that gap. The stakes are high. Without coordinated action, public policy will continue to lag behind technology, leaving children exposed to risks that could have been mitigated through thoughtful design. But with the right frameworks, governments can ensure digital systems respect children’s rights, support healthy development, and promote well‑being. IEEE’s emerging standards and collaborative technology policy work offer a path forward. By grounding national efforts in evidence‑based, rights-aligned design principles, IEEE is helping governments move from reactive regulation to proactive, coherent, and globally informed strategies for protecting children online. Safeguarding childhood in the digital age is both a moral imperative and an engineering challenge. And IEEE is helping to lead the way. —Mary Ellen Randall IEEE president and CEO Please share your thoughts with me: [email protected]. This article appears in the June 2026 print issue.
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[Note that this article is a transcript of the video embedded above.] If you have a fluid-filled system of pipes in your life, whether liquid or gas, (and who among us doesn’t?) there’s a very good chance that it passes through a simple device at some point on its journey to you. This device is almost unbelievably reliable for a purely mechanical system, and it has changed very little since the mid 1800s. So reliable that there’s a good chance you’ve probably never serviced or replaced one and maybe never even noticed one, despite them controlling so many aspects of our everyday lives. Of course, I’m talking about pressure regulators. But don’t let the jargon bore you, because these things are fascinating. They’re basically Victorian-era mechanical computers, and I cut one in half so we can see how it works. I’m Grady and this is Practical Engineering. “Control theory” is the branch of engineering that we use to describe managing dynamic systems, including the flow of fluids in pipes. I have a bunch of videos and demonstrations of just how dynamic those systems can get. A fundamental idea in this field is that, to garner any amount of control, you need some kind of feedback. And this is not a complicated idea. Say I want to control the pressure in my garden hose. I can put a pressure gauge on it, look at that gauge, and adjust the valve until I hit my setpoint. If something changes, like someone flushing all the toilets in the house simultaneously, I’m the feedback loop. I look at the gauge and make the change to get the pressure back to where it’s supposed to be. In fact, this exact situation (more or less) contributed to the pressure regulation equipment that we know and love today. The legend goes that in 1876, a massive fire broke out in Marshalltown, Iowa. William Fisher, a city engineer, spent all day and all night adjusting the throttle on steam-driven pumps by hand to manage the water pressure in the system to help the firefighters. Exhausted by the effort, he went on to develop the constant pressure pump governor, a precursor to the modern pressure regulators that are absolutely ubiquitous today. And I really mean that. Let’s take a little tour. One of the easiest regulators to find is on an air compressor. You generally want the reservoir as full as possible, which means pressurizing it to a level higher than what you would actually want out of the hose. Every air tool has its own maximum pressure, so you have a knob like this so that, no matter how much higher the pressure in the tank is, you get a consistent and controllable pressure out. If you use pressurized tanks of gas like oxygen, argon, or propane - exact same thing. You’re almost always going to see a regulator on top to control the pressure leaving the tank. Maybe you have a natural gas connection to your house. In most cases, residential plumbing and appliances are designed for very low pressures, like a half a psi or about 30 millibar. That’s great for getting gas from your basement up to your kitchen, but it’s hard to get gas to flow long distances at those pressures, so the lines feeding houses are usually at pressures quite a bit higher. You don’t want high pressure explosive gas in the walls of your house, so it has to be regulated down at the meter. That’s the pancake shaped device you often see outside. Even a standard pressure cooker has a regulator on top. A weight on top of a small pipe balances the steam pressure inside, providing only enough release to maintain a constant pressure inside. It’s not just gases either. The pressure in your water main can be too high for residential plumbing, so you might have a pressure reducing valve on your water service line. Most internal combustion vehicles have regulators that manage fuel pressure between the pump and injectors. And, of course, there are countless industrial applications of pressure regulators used in factories, power plants, and more. If you can find a pipe anywhere in the world, there’s a good chance that, no matter what’s in it, somewhere along it is a pressure regulating device. By the way, the stakes associated with pressure regulation are extremely high, particularly when it comes to natural gas. In 2018, the Merrimack Valley in Massachusetts saw over a hundred structures damaged by fire and explosions, 22 people injured, and 1 dead all as part of a single incident. It all came down to a mistake made during a pipe replacement project that kept the regulators from working correctly. This was a system where pressure was regulated down at a district level instead of each individual meter. The mistake sent natural gas into homes and businesses at pressures way above what the plumbing was designed to handle, ultimately resulting in one of the worst natural gas disasters in American history. I covered the whole story in a video a while back if you want to learn more after this. Here’s the thing: it’s not that complicated to reduce the pressure in a stream of fluid. Basically any kind of obstruction to the flow will do it. A simple way to do it is to put a flat plate with a hole inside the pipe. But a graph will show you why it’s not quite that easy. Let’s assume you have a constant pressure on the inlet side. If you graph the outlet pressure as a function of flow rate through the pipe, you don’t get a flat line, but a curve. And, critically, when there’s no flow, the pressure on the outlet side is the same as the inlet. There’s no reduction at all. If you let the pressure on the inlet vary, things get even more complicated. It’s easy to see why a static device, like an orifice plate, is not a very good regulator. There’s no feedback and no control. You definitely get a lower pressure in some situations, but if you need a consistent pressure that doesn’t exceed some maximum level, this is not going to work. Early gas regulators were bulky contraptions, but actually pretty simple. You could suspend an iron bell in a tank of water. A cast iron cone was attached to the top of the bell, sliding inside the inlet pipe. If the pressure inside the bell rose, it would float upward, pulling the cone too. The higher the cone is, the more restriction you get on the inlet pipe, decreasing the flow to maintain a consistent pressure leaving the device. It’s a pretty clever invention, but not entirely practical. The water level had to be maintained; it could freeze or get gross; the metal corrodes. And importantly, when it failed, it didn’t fail safely. If the bell sprung a leak or the counterweight cable broke, the cone would fall downward, fully opening the inlet. Modern regulators have a few features that improve on the original idea, and I happen to have a natural gas regulator so we can take a look inside. This is a used regulator that probably came from a large commercial building or a light industrial setting. And it’s actually built by Fisher Controls, the company William Fisher started after his firefighting pump throttling experience. Not a sponsor, but I like to think he would appreciate us cutting it up to learn more about it. I tried to be strategic about this to allow a look inside without it completely falling apart. From the outside, it kind of looks like gas would make a straight shot through, but when you cut it open, you can see that there's a separation here where the regulator connects to the line. I have it set where the discharge is pointed down. Gas has to pass through this valve to make it to the discharge side, and you can see that, past the valve, the discharge side is connected to this chamber in the main body of the regulator. Inside the chamber is this flexible membrane called the diaphragm sandwiched between the two sides of the housing. It’s a little floppier than usual, since I cut the whole thing in half, but hopefully you can still see how this works. This regulator has a stiffening plate attached to the diaphragm that acts against a spring at the top. The spring is a little too stiff for me to show you the full range of motion, so I’m going to take the seat off just to demonstrate. Let’s say there’s no demand for gas downstream. In that case, the pressure in the discharge line will build up, pushing the diaphragm upward. The diaphragm is connected to this lever, which is connected to a poppet, which pushes up against an orifice to close the valve, preventing gas from flowing. Let’s say someone opens a valve downstream, like a stove or a heater. As the gas flows out of the system, the pressure in the discharge line will fall, reducing the pressure on the diaphragm. The spring at the top will push the diaphragm down, lowering the lever, and opening the poppet so that gas can start flowing. If the demand increases, the pressure will drop further, lowering the diaphragm and opening the valve even more. And this system will constantly adjust to the downstream pressure, throttling the valve to keep it consistent - a completely mechanical control loop maintaining equilibrium. Any difference in the setpoint and actual downstream pressure creates a proportional movement of the diaphragm and poppet valve. And it’s adjustable too: The compression of the spring at the top can be increased or decreased, which allows you to dial in the exact pressure the regulator will supply. This is just so impressive to me. It’s a dead simple idea, but it does such an important job. But one of the difficulties, especially with natural gas, is that, like all mechanical devices, there’s some friction in the system. I mentioned that the downstream pressure of natural gas is pretty low. This regulator has an outlet range of about 1.5 to 3 psi above ambient air pressure, or about 100 to 200 millibar. Force is pressure times area. If the area of the diaphragm was small, the total force from the gas pressure acting against the spring would be practically indistinguishable within that range, especially when you consider the friction of the lever and valve. That’s why the diaphragm in natural gas regulators is so big. Even small changes in pressure create large difference in force, so you get more sensitivity, and the valve positions are more closely tied to the actual changes in pressure. You might see an issue with this design though: For the valve to open wider to allow more flow, the diaphragm must move down. For the diaphragm to move down, the pressure holding it up (the downstream pressure) must drop. Engineers call this droop, which I love. But there is still some variability in the downstream pressure. Pressure is tied to the valve position, so it’s necessary that it be allowed to fluctuate some. It will never be rock solid in this model. If you need that, the solution is usually a pilot-operated regulator. In this design, the downstream pressure is connected to a tiny, ultra-sensitive pilot regulator, and that regulator basically uses the higher-pressure inlet gas to move the main valve. In this way, you can go from 0 percent to 100 percent flow with almost no change in downstream pressure. Regulators can also be sensitive to inlet pressure. You can see on my model that the inlet pressure acts against the spring to open the valve. Of course the valve is a lot smaller than the diaphragm, so the effect isn’t as big, but there’s still a relationship between inlet pressure and outlet pressure, which isn’t always ideal. A lot of regulators work the opposite way, where the inlet pressure acts to close the valve. If you use a regulator on a tank, this can cause the counterintuitive issue of discharge pressure spiking as the tank empties, since the inlet to the regulator isn’t pushing as hard to close the valve. If you want to reduce this sensitivity, you can use a two stage regulator where you drop the pressure in steps. Let the first stage handle the coarse reduction, providing a more consistent inlet pressure to the second stage which can then keep the discharge pressure rock steady. One thing this regulator doesn’t do is fail closed. If this diaphragm rips, the outlet pressure won’t be able to push it upward to close the valve. So we have to account for that potential in other ways. Lots of gas systems will use a secondary, redundant regulator set to a slightly higher pressure that will take over if the primary fails. There is also a circuit breaker equivalent for gas systems called an overpressure shut-off or slam-shut. This model uses another option: an internal relief valve. Say the pressure on the discharge end somehow got too high. Maybe something got stuck in the valve, keeping it from fully closing. Or maybe the discharge line was exposed to sunlight, expanding the gas inside. In this case, the diaphragm can bottom out and act against this secondary spring, lifting off this plate. Gas is allowed to escape through a hole in the center of the diaphragm into the top half of the casing and out of this vent hole. And here we have another valve called a flapper. It can open inward to balance the pressure inside the regulator. And it can open outward if the relief valve activates, letting the excess pressure escape. The regulator would normally be mounted like this so the vent points downward, keeping rain out. And it has a screen so bugs don’t make a home inside. Obviously, this has some tradeoffs. This regulator has to be mounted outside or be attached to a ventilation pipe running outdoors to make sure it’s not releasing gas into a closed space. Even so, you don’t necessarily want to vent a bunch of natural gas outside. But because of the odorant that’s added to it, the idea is that someone would notice pretty quickly that some part of the system is malfunctioning and shut the line down for repairs. Like every part of engineering, it’s a game of tradeoffs: pressure versus flow, capacity versus cost, accuracy versus redundancy, and safety here versus safety there. I just love that there’s stuff like this out there, pretty much anywhere you’re willing to look, doing an essential job that few people even consider, and that their basic function really hasn’t changed in centuries. Samuel Clegg, one of the early engineers in natural gas systems had this to say about the pressure regulator: “Its use is nowhere sufficiently appreciated. Had it been a complicated piece of machinery, or expensive in its first cost and after application, objections to its adoption would not have been surprising; but it is perfectly simple: its action is certain and unvarying, and its first cost inconsiderable.” Nearly 200 years later, I couldn’t have put it any better myself.
TLDR: yes, models are getting funnier over time I love laughing. Well, who doesn’t? Good jokes have a certain notion of cleverness to them and I do believe that great comedians display high intelligence. Cracking a good joke requires astute observations about odd situations, and linking them to something we find familiar. Jokes are hard!… Read More The post How funny are the frontier AI models? appeared first on Inverted Passion.
The biggest empire the world has ever seen was run by a small elite who partied all night, drank liters of port, and stayed in bed until the afternoon.
Turbulence is all around us: bumping our planes, roiling our rivers, swirling milk into our coffee. These systems quickly become extremely chaotic and complex. On this episode of The Quanta Podcast, host Samir Patel speaks with contributing writer Stephen Ornes about a recent study that used sea monkeys to complicate one of turbulence’s many mysteries. This topic was covered in a recent story for Quanta Magazine. Each week on The Quanta Podcast, hear the people behind the award-winning publication navigate through some of the most important and mind-expanding questions in science and math.
The past and future of the “world’s back office.”