Human behavior is complex and can be very difficult to predict. This is one of the challenges of safe driving – what to do when right of way, for example, is ambiguous, or there are multiple players all interacting with each other? When people learn to drive they first master the rules, and learn their driving skills in controlled situations. As they progress they gain confidence driving in more and more complicated environments. Even still there are about 17,000 car accidents per day in the US.

It should not have been surprising, therefore, that autonomous or self-driving car technology would also find the task incredibly challenging. Self-driving algorithms not only have to learn the rules, and master the basic technology of sensing the environment with sufficient accuracy and in real time, but also to master increasingly complex and inherently unpredictable environments. A decade ago, when the technology was rapidly advancing, enthusiasts predicted that the technology would be essentially ready for the mass market by the early 2020s – so, now. But they realized that the last 5% or so of performance ability was perhaps more challenging than the first 95%. Some problems become exponentially more difficult to solve when new variables are added (we still haven’t solved the three-body problem). We have seen this with other technologies, like fusion, general AI, speech recognition, and some applications of stem cells, where early predictions were overly optimistic.

This is the challenge that AI specialists are working on now – how to get self-driving car AI systems to perform well-enough to handle the challenging situations that crop up with regularity while driving? The further complicate the issue, these systems have to function in real time, so the solution cannot involve a dramatic increase in computing that would slow down the whole system.

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According to the WHO, one third of the people in the world lack access to safe drinking water. They report that, “Globally, at least 2 billion people use a drinking water source contaminated with faeces.” Some locations (like the island of Bermuda) lack any supply of fresh water, and depend largely on rainwater. While a lot of progress has been made over the last few decades, this remains a huge problem. It is also likely to be exacerbated by global warming and an increasing population. A proper sanitation infrastructure is the ideal solution, but in the meantime anything that can supplement supplies of drinkable water will help.

One technology that has been around for decades and is often pointed to as a potential solution is desalination, taking the salt out of salt water. If we can economically do this, then we could just get our fresh water supply from the ocean or from brackish sources. There are plenty of commercial options available, like this one, that uses reverse osmosis and filtration to desalinate and purify water. Even in developed nations desalination plants are becoming more common, as demand increases, and also to create a reliable local source even during times of drought. California has 11 such plants, like this one north of San Diego that produces 50 million gallons of fresh water per day.

There is also a use for small portable desalination options in poor or remote regions that lack access to centralized sources of clean water. Portable options can also be useful during disasters, or when demand spikes due to heat waves or droughts. Portable “suitcase” sized desalination devices already exist and can be purchased commercially. The SeaWater Pro, for example, costs about $6,000 and comes in a portable hard case. It comes in two options, a plug-in and one run by a lithium-ion battery. The battery option could also be paired with a portable solar panel, which range from a couple of hundred to a few thousand dollars depending on how much power you need. This device produces 10 gallons of fresh water per hour, or 240 gallons per day (if plugged in). That is enough to serve a few families or even a small village.

A recent study examines a new approach to portable desalination, using “multistage electromembrane processes, composed of two-stage ion concentration polarization and one-stage electrodialysis.”  The study demonstrates that the technology works, producing drinkable water up to the WHO standard starting with either brackish water or sea water. The advantage of this system is that it does not require filters, so nothing that needs to be regularly replaced. It is therefore a more independent system. A battery-based system has been field tested, and the authors report that: “The demonstrated portable desalination system is unprecedented in size, efficiency, and operational flexibility.” Continue Reading »

As we try to transition as much as possible away from fossil fuels, jet fuel remains a tricky problem to solve. Jets, like rockets, require a fuel with a high energy density (energy per volume) and specific energy (energy per mass). For rockets the specific energy is far more important – mass is everything, due to the rocket equation – and so perhaps the ideal fuel for rockets is hydrogen, because it is so light. For jets, however, energy density is also very important because there is only so much volume in the fuel tanks, and making them bigger can be counterproductive.

Jet fuel has another requirement. O-rings are used to seal metal-on-metal joints in the fuel tank and engine. In order for these O-rings to work optimally they have to swell during engine operation, a property known as seal-swell. Currently aromatics are added to jet fuel because they cause the seals to swell. In fact, this has been a huge hindrance to the use of replacement and more sustainable jet fuels, because they lack adequate seal-swell properties.

A new innovation, however, may have solved this problem. The researchers developed a lignin-based jet fuel additive (LJF) with several desirable properties. Here’s the highlight: “A new LJF is reported primarily composed of C6-C18 mono-, di-, and tri-cycloalkanes.” They tested a 10% blend of their new LJF with conventional jet fuel and it increased the fuels energy density and specific energy, both highly desirable effects. But perhaps more importantly, the LJF additive had great seal-swell properties. It could therefore replace the aromatics in the jet fuel.

This is important for the project of creating sustainable jet fuels because the aromatics have a significant negative impact on the environment. They produce a lot of soot when burned and contribute to contrails.  Contrails contribute to global warming, perhaps even more than the CO2 released by burning jet fuel. Reducing or eliminating soot from aromatics and the resulting contrails could significantly reduce the contribution to AGW from jet travel. As a blend the LJF, which is a biofuel, displaces fossil fuel, and by making the fuel more energy dense reducing overall fuel use.

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Are we headed for a world in which most of the meat we consume was grown in a vat rather than in an animal? This is a fairly high-stakes question (pun intended). We have a growing population, we are already using most of the arable land available, and we are pushing the efficiency of agriculture. There is still some technological head room, mostly with GMO technology, to improve yields further. But we are already use more land than is optimal to feed ourselves, as well as a lot of water, and consuming a lot of energy, which has a carbon footprint. Anywhere we can achieve efficiency can have a huge impact, therefore.

The animal product industry is the focus of a lot of attention by environmentalists because of its inherent inefficiency. There are different ways to look at this. Cattle consume about 25 calories for each one they produce, pork is about 15, chicken 6, and fish is close to 1:1. But we can also look at calories produced per acre of land, in which case the comparison is not as clear.

One way to look at the issue is calories produced per acre of land. Here beef has the worst ratio, with 1.1 million calories produced per acre (I assume this is per year, although it is not explicitly stated in the linked reference). Potatoes are very efficient at 17.8 million calories per acre. But soybeans are also pretty inefficient at 2.1, while pork is more efficient than soybeans at 3.5. The ratio of efficiency between potatoes and soybeans is about the same as the ratio between wheat (6.4) and beef.

Some types of meat are more land-efficient than some plants, but yes, overall, plants are more efficient. The picture is also complicated because animals can produce high-quality nutrition and can use land not suitable for growing plant-based food. Simplistic comparison therefore breakdown when you look at a more complete picture. But I think it is scientifically non-controversial to say that the typical Western diet includes too much meat, and if we cut down it would improve the overall efficiency of our food production in terms of land, water, and carbon. This is a low-tech solution that is likely optimal for health and the environment.

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I am happy to announce that pre-orders are open for my upcoming book, The Skeptics’ Guide to the Future, which will be released by Grand Central Publishing on September, 27th. You can preorder your book here.

This was a particularly fun book to write, with my two brothers, Bob and Jay (who also co-host the SGU podcast with me). This is our second book, with Evan and Cara also contributing to the first one (The Skeptics’ Guide to the Universe). In this new book we explore futurism itself – what have we learned from past attempts at predicting the future and how can we use those lessons to perhaps do a little better? We explore, for example, what I call “futurism fallacies”, common errors in trying to extrapolate our world into a vision of the future. One common fallacy is to extrapolate current trends indefinitely into the future, even though this is generally not the path that history has taken. Disruptive technologies, changing priorities, the interaction among various types of technology, and evolving culture all introduce zigs and zags into the course of history, and therefore the future.

Is futurism, therefore, doomed to failure? This is actually a matter of scholarly debate, with critics and advocates. Overall I think predicting the future is similar to predicting the weather – while it is impossible to predict the details beyond a very short window, we can make broad predictions about the climate. Similarly we can say that technology will not only continue to advance but the pace of that advance is accelerating. We explore those individual technologies that are just emerging and most likely to have a profound impact on our future, such as genetic engineering, additive manufacturing, artificial intelligence, and metamaterials. There are also some established technologies that will continue to advance, expanding into new niches, such as robotics.

We also discuss technologies that are just in the conceptual stage, and give our opinion as to whether or not they are likely to ever come to fruition. We will likely have fusion power someday, but I doubt we will ever have a space elevator (at least not on Earth).

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Would you get a readable chip implanted in your hand? In a 2021 European survey 51% of people said that they would. What are the risks and potential benefits of the technology as it currently stands?

There are currently two main technologies for implantable chips that can be read at close range through the skin. The more familiar technology is RFID – radio frequency identification. There is also Near Field Communication (NFC) which is a type of device that uses short range connections, less than 4cm. Both NFC and RFID use radio frequency wireless communication. They are activated by coupling with an external antenna that allows one-way or two-way data communication. The devices are therefore passive, they do not require their own power, which is a huge advantage for something implantable.

This is the same technology used in wireless card readers or similar non-implantable technology. The real difference is that these chips are designed to be implanted, so that are small (slightly larger than a grain of rice) and are encased in a bioplastic that is tissue compatible. The first such chip was implanted in a person in 1998. They have been used routinely for implantation in pets. They are FDA approved for implantation in humans, and the data shows that they are medically safe. They are also MRI safe, meaning that (despite rumors) they won’t explode, overheat, or move if a person with a chip implant goes through an MRI scan. However, some brands may not be MRI compatible, meaning that the data on them may be wiped or destroyed by the MRI scan. This is likely a solvable problem, however. Chip designs could be made MRI resistant. It’s also theoretically possible to put on a glove that would shield the chip to reduce or avoid damage.

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Have you ever done the thought experiment where you imagine yourself back in time, in a technologically primitive society? What would life really be like, and what could you do to improve it? We are fairly dependent on our modern technology, and that does not give us the knowledge or skill to understand pre-industrial technology. Would you know how to design and build a flush toilet, for example?

But I have also come to realize that this thought experiment reflects my bias coming from an industrialized nation. You don’t have to go back in time to confront the challenges of lacking electricity, basic sanitation, or clean water. You just have to visit poor and developing parts of the world today. It’s not exactly the same situation, because the technology exists somewhere in the world, but that is not much help to the 1,800 children who die every day from diarrhea from contaminated water. This is another way that our developed-nation bias might manifest – I tend to get interested and excited about advances in technology at the cutting edge, squeezing another 10% out of the energy density of Li-ion batteries, for example. But the technologies that might help the most people are those that can bring basic affordable services to poor countries.

More attention is being paid to this problem. Low-income countries (LICs) lack the resources and institutional infrastructure to invest in the kinds of research most likely to benefit them, while high-income countries (HICs) are much better at leveraging research to improve their economies and standard of living. We tend to think of the X-Prize as progressing the most advanced technology, but even they are turning their attention to basic problems, such as literacy.

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There are many ways to generate energy, and as we try to wean ourselves off of fossil fuels researchers are exploring how to improve and expand upon our options. One category of energy production is bio-energy, deriving energy from a biological source. Currently this mostly comes in the form of biofuel. Plants evolved ways to make energy from sunlight billions of years ago, in the process of photosynthesis. The captured sunlight is essentially stored as high-energy molecules, and those molecules can be converted into other high energy compounds, like ethanol, that can then be burned as fuel.

The problem with growing and harvesting biofuel is that it is inefficient. The amount of energy produced per unit of land is lower than other forms of energy, arable land is in short supply and will only get shorter as our population grows. Further, the process uses a lot of energy and while we can generate net energy through biofuels, the ultimate yields can be quite low. For these reasons I don’t think biofuels will ever become a major contributor to our energy infrastructure. However, it will likely have a niche, if not to power cars than in industry, which also needs to be fed high-energy compounds for many processes. There are also opportunities to use as feedstock for biofuels organic matter that would otherwise be waste. Researchers are also working on growing microbes in vats to improve land efficiency, or growing plants in the ocean to use as feedstock. These methods will help, but we will still never be running the world on biofuels. The numbers just don’t add up.

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OK, I’m a sucker for juicy battery news, even though I know these advances are all incremental and not the dramatic “breakthrough” they are often presented to be. But cumulatively these incremental advances are significantly increasing the energy per mass and energy per volume of high-end batteries. This is a critical technology for our low-carbon future, and so these advances are worth tracking.

As I always point out when I write about battery technology, an ideal battery needs to have many features simultaneously: good specific energy, energy density, lifespan in terms of charge-discharge cycles, rapid recharge rates, sufficient power, use of cheap, abundant, and non-toxic materials, a good temperature range of operation, overall cost-effectiveness, scalable manufacturing, and stability (it’s nice if they don’t spontaneously burst into flames). Li-ion batteries are the current state-of-the-art because they are reasonable to good on all these parameters, but there is a lot of room for improvement. One of the many lines of research looking into alternate battery design is solid state Li-ion batteries. These use a solid rather than liquid electrolyte for conducting charge between the electrodes.

A solid state design could have twice the specific energy (energy per mass) and twice the energy density (energy per volume) as current Li-ion batteries.  This is because the solid electrolyte requires much thinner separators between the electrodes, and also because the lithium-graphite electrode can be replaced with a lighter pure lithium electrode. Solid state batteries also will likely have a longer lifespan and are more stable and therefore safer. Imagine essentially doubling the capacity of a lithium battery, for your cellphone, laptop, or electric vehicle. You could increase the range of an EV by 50% while still decreasing the battery weight by 25% (which would actually increase the range a bit more). I own an EV with a range of 350 miles, and going to a range of 500 miles would definitely reduce range-anxiety on long trips. That might be the sweet spot for EVs.

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One of the themes in my upcoming book (that I wrote with my brothers, Bob and Jay) about future technology (coming Fall 2022) is the frequent disconnect between science fiction visions of the future and actual future technology. We can look at past science fiction about today and see how they did, but we can also look at current science fiction about the future to see how plausible their vision is. It’s a mixed bag, but one area where the disconnect is very strong is space travel. The problem is that space travel really sucks, and is going to suck for the foreseeable future. This is not only true for interstellar travel, but even travel within our own solar system. But science fiction authors want their action to take place in space and have their heroes travel to different worlds. So essentially they either need to just ignore major hurdles to space travel or make up sci-fi technology to solve those problems even if that means ignoring current science. Even hard science fiction has to allow 1-2 “gimmies” to make the storytelling work.

I think all of the challenges of space travel are potentially solvable. But I also think those solutions are going to be more complicated, involve more trade-offs, and take much longer than science fiction authors generally imagine. Toward that end, NASA is funding innovative research projects to chip away at the technological challenges of space travel. While these are early (phase I and phase II) research projects, they give a much more realistic glimpse into what space travel might look like over the next couple of centuries. Here are some highlights:

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