omenti

a watson lecture with carver mead

Carver is one of the most important engineers of the 20th century - a great lecture on some of the events that occurred around him at Caltech over the years.  He's 90..  the lecture is a few months old. Highly recommended - particularly if you're interested in invention, innovation and transformation.

creating the arrow tips

To start off you need to subscribe (free) to the Crazy Stupid Tech newsletter from Om Malik and Fred Vogelstein.  A couple of paragraphs from their introduction gives a sense of where they're going:

 

Together we have followed Silicon Valley’s innovation engine for decades. We've seen a lot. But one observation stands out: The best ideas - the ones that launch meaningful companies - need to seem crazy and stupid at first.

We get that tech makes many of us more nervous than hopeful right now. But as Silicon Valley’s influence extends deeper into all corners of our economy and lives, there also have never been more interesting, crazy, stupid new and interesting technologies out there. They are not getting enough attention. So our goal is to tell you about them.

 

I've been involved in a variety of technologies from application to tools, but I'm a bit of an outlier.  My background is fundamental physics - something I've been able to mostly keep up since grad school while doing other things and what consumes most of my time these days.  It's non-linear and the payoffs often don't arrive for decades and rarely for those who did the work.  But over time it's where almost all technologies come from as well and a number of powerful tools.  It's difficult to quantify the payoffs, but most numbers exceed one hundred time return in investment after factoring in inflation - and that includes a large number of paths that didn't work out.  It may come as a surprise, but this is a case where the liberal arts win over time.¹

 

A secondary effect is the training.  Get to the point of a postdoc in physics and you begin to think like a physicist.  The same for chemistry and probably many other areas.  Sometimes this ability to 'think different' is useful in more applied areas - particularly when it comes to stepping outside just a bit.  Of course you probably don't want a room full of physicists, chemists and mathematicians working on finance .. well .. unless you happen to be Jim Simons, but he was probably an outlier. 

 

This kind of research, often called curiosity-driven or discovery research, has been increasingly under fire in the US and EU for about thirty years. Funders are much more interested in some kind of payoff - more of an applied research (although that term is used for something else in industry).  This has happened before and I suspect we'll see a swing the other way as China takes over as the leading scientific power.

 

I'm not discounting applied research.. more of it needs to be done and I suspect a better focus is required.  The enormous sums of money and numbers of people going into computer science for gAI strikes me as mis-targeted and wasteful given more pressing challenges around global warming, inequality in healthcare and so on.

Finding the right mix of people and research areas at the fundamental end demands a great deal of good taste.  A few organizations have been very successful: Cambridge was behind in sorting out issues of telegraphy and the likelihood of radio, but decided to work on fundamental issues of thermodynamics.  They managed to assemble some of the best minds and created the modern research laboratory.  They created the spark that launched quantum mechanics which exploded in the 1920s.  In the teens Caltech was a sleepy little engineering school that found itself with a new mandate.  They decided not to work on  the transmission of electricity like everyone else.  By going deeper they managed to become one of the more relevant pure research organizations for the next century.  There are other examples like Bell Labs which had about six decades.  To be fair it was mostly applied research, but there was a core that changed the world.

 

There's an interesting form of teamwork at these places. People tend to talk to each other a lot.  Places like the Perimeter Institute have blackboards in nearly every room and hallway.  Each table in the cafeteria has notepads and pencils to facilitate the discussions that flow across groups and through the building. Setting direction is an art that is often based on a perception of beauty. It's similar, but slower in the experimental laboratories and there's something of a competition and balancing act between theory and experiment.   It may seem like herding cats and it's messier and more inefficient than the so-called scientific process, but it turns out to be the most efficient way to create possible futures.  It's an act of faith that learning more about the Universe is important to humanity.  Of course it takes time along with the insight of people with different skills to turn that into reality and Crazy Stupid Tech will probably give some insight into that direction.

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1 The physical science and math are part of the liberal arts as opposed to professional and technical fields. 

 

 

beyond david mackay?

a minipost

David MacCay was a remarkable fellow.  Curious and cross-disciplinary, he worked in applied math, physics and engineering research at Cambridge.  Passionate about doing something about global warming, he happened to be a great communicator.  I had a few interactions with him: first about thirty years ago playing with neural networks and later in the mid 2000s as he was putting together Sustainable energy – Without the Hot Air - probably the clearest book written on energy production and demand.  You can still buy the book and  proceeds go to support some good charities.  David updated the book online until his early death in 2016.  It's free online, but the printed version is a better experience.

 

The book is written at two levels - one for folks without a mathematical background and a somewhat deeper version that assumes an understanding of high school physics. David goes into depth building easy to understand models and then plugs in numbers from past and present technologies.  The last step is where the book is flawed.  Enormous advances have been made in solar and wind power technology and prices have fallen dramatically.  A few of David's conclusions relevant ten years ago are now dated.  For example he shows that wind power and solar are insufficient for the UK, even in an ideal world without existing infrastructure and bureaucratic inertias. The last two roadblocks still exist almost everywhere, but the underlying story has changed.

 

Brian O'Callaghan's group at THAT other English university have published an updated look at solar and wind energy in the UK and come to the conclusion that they are practical and nearly sufficient at scale.  Here's the summary of their policy paper.  Their technical papers are solid and thorough.   I suspect Sir David would be proud.

 

In addition to getting an important  update, there's an important lesson here.  When describing current and future technology scenarios it's extremely important to lay down some clear thinking that is largely independent of current and future inputs.  The basis of this type of scenario is really just a solid foundation that's waiting for inputs.   It's rare to see ones that work twenty or  more years in the future.   David's did and does... it just needed updated inputs.

 

 

 

a return to mount hydrogen?

Usually she buys the same number as her age, but this year she rented a small helium tank that ended up filling 56 balloons.  For the past ten years Jheri celebrates her birthday by giving balloons away to kids and adults who look like they could use one. 

 

We think of helium in terms of balloons but, particularly in its liquid form, it's uniquely suited to a number of important applications.  First discovered when astronomers analyzed the spectrum of a total solar eclipse in 1868 and then later found on Earth, it became part of a race between an English and Dutch scientist.  Not because getting there first would lead to uses, but rather to scale a peak. 

 

By the mid 19th century Michael Faraday managed to get down to about -130°C.  It seemed almost impossibly cold at the time, but wasn't enough to liquify oxygen, nitrogen and hydrogen.  He conjectured the trio were permanent gases. About that time Sir William Thompson (later known as Lord Kelvin) deduced from the emerging science of heat, that there was a coldest temperature.  An absolute zero  -273.15°C.  Well below Faraday's mark, it gave hope that much more was possible.  Sir James Dewar, at the Royal Institution in London, had been refining techniques to go to very low temperatures and took up the challenge.  It didn't take long for him to liquify oxygen and nitrogen, but hydrogen proved more difficult.   The Dutch scientist Kamerlingh Onnes was also entered the game.  It was an expensive and even dangerous quest.  One of the great stories of science follows.  Onnes was the good guy, Dewar not so much.  I won't go into it, but there's an excellent half hour audio history with a transcript.  Listen to it - seriously - then the title of this post might make sense) Without spoiling things too much, Dewar got there first, but helium had been discovered.  There was another gas to try and liquify and race got much more serious.  

 

Almost all of the helium on Earth is produced by the radioactive decay of Uranium and Thorium and is trapped in a few pockets around the planet.  That wasn't known at the time and it was basically unobtainium.  Dewar's personality caused him serious delays and his relentless push led to serious accidents that injured himself and lab assistants.  Onnes was banished from his town ..  (listen to the audio)

 

Now that he had liquid helium, Onnes, began to study the bizarre liquid.  Curiously the electrical resistance in mercury lowered to liquid helium temperatures fell to zero.  Onnes coined the term superconductivity.  A few other materials have this property.  It allows you to build extremely powerful magnets which are used in MRI machines, maglev trains, particle accelerators and fusion reactor research and more.  Almost all of the practical superconductors require liquid helium temperatures.  Being able to do this at warmer temperatures would be revolutionary.

 

In 1986 I was a the big annual meeting of the American Physical Society when Bednorz and Müller of IBM announced they had found superconductivity in a ceramic at liquid nitrogen temperatures.  Pandemonium broke out and it was on the front page of the New York Times the next day. It's very unusual for a Nobel Prize to be awarded soon after a discovery, but they were in Stockholm for the ceremony the next year.   The material wasn't terribly useful, but it opened up new area of research.  

 

Superconductivity at liquid nitrogen temperatures (77 K, -196°C)  is appealing as LN₂ is very inexpensive and relatively safe.  (Karrie and I have both made ice cream with it:-)  More progress has been made with superconductivity at liquid hydrogen temperatures  (20 K, -253°C).  LH₂ is flammable, tricky to handle, and somewhat more expensive, but is almost free when compared with helium.  And now practical superconductors for a few uses exist at LH₂ temperatures.

 

If Mount Hydrogen can be economically scaled for a wide range of superconductors, any number of applications where high magnetic fields are important become much more practical. Cheaper MRI, maglev, large motors and generators and beyond. It could bring electric aviation closer.  Moving to LN₂ superconductors levels much larger scale applications emerge.  Perhaps important sections of the electric grid, public transportation and nuclear fusion reactors (the magnets, not the fuel.. plus it's probably a loooong way off)

 

It quickly gets technical, but a class of superconducting materials that work well at liquid hydrogen temperatures have been around for awhile, but manufacturing them (you find yourself looking at single crystals over a kilometer long) is difficult and expensive.  But demand, driven applied science work in fusion reactors,  has soared recently and new manufacturing techniques have appeared.  Production has grown from meters of wire to hundreds of kilometers.  Costs are now within a factor of four or five of a tipping point for widespread use.  The problems ahead are difficult, but probably solvable. In ten or fifteen years we may see the beginning of widespread use of these materials and even serious progress at liquid nitrogen temperatures. 

 

The audio piece I linked to describes the lowest temperature made on Earth in about 2004.  The record has fallen - it seems likely the coldest spots in the Universe are in physics labs around the Universe - hopefully more than just the ones on this planet.

 

 

bondi blue

a minipost

Ask elite beach volleyball players to name their favorite beach and Bondi Beach often comes up.  The sand isn't world class, but the water - that amazing blue - can take your breath away.  There's a bit of a controversy on pronunciation, but I've heard an Australian player go with bond-eye.

 

About twenty five years ago Steve Jobs had to bring Apple back from its near-death experience.  There wasn't much in the way of in-house new technology, but Jobs had Jony Ive as well as his own taste.  They went with the iMac.  A strangely shaped, but very cute, little computer with a semi-translucent bondi blue case.  Pundits noted there wasn't anything new except design and pronounced it and Apple dead on arrival.  Apple sold enough to buy time for for the transition to an operating system and later a processor migration (one of two!), all the time working on "company-killing" products like a portable music player and a smartphone. 

 

The surprise success of the iMac set off a tidal wave of design element copycats.  Suddenly everything from routers to hair dryers sported translucent cases - often in bondi blue.  As far as I can tell the new design language didn't case a sensation in any of the non-Apple markets.

In the past month I've seen partly thought-out plans to include LLMs like ChatGPT in some way into existing or newly dreamed up products.  None of them were clearly articulated. Somehow ChatGPT or an equivalent would supply the appropriate magic.  LLMs have become the new bondi blue (bondization?)  There are clear usage cases as well as those that aren't.  I suspect a lot of money will be burned with a single digit survival rate .. sort of what one sees during Cambrian explosions.  

 

I won't comment here on the dangers of these technologies other than noting regulation is necessary with a well-defined "open", ownership of rights to all training data, evolution of regulation, etc.  History across many industries tells us industry shouldn't be involved in its own regulation.  

 

 

 

peak oil - really?

Once a year I read BP's Energy Outlook.   They have a record of serious greenwashing, so anything from them (or the other fossil fuel companies) requires a bit of skepticism, but this year's report took a turn from the normal path. They suggest global oil demand peaked in 2019.  There have been any number of 'peak oil' predictions, but most refer to extractable supply - a bit more on that later.  While the BP predictions are more scenarios than rigorous predictions, it's significant that a large oil company believes oil demand is, and will continue to, drop.  

 

BP outlines three scenarios: Accelerated, Net Zero and New Momentum.  I'm guessing they'd prefer the New Momentum scenario, and will probably lobby and use other tactics to move in that direction, but the bottom line is they see less oil coming from the ground.

 

I think they're transportation modeling is too conservative. Electrification will probably take place much more rapidly than predicted.  Granted there's a lot of inertia in fleet replacement given how long cars last, but the assumptions strike me as too  slow.  They don't seem to be taking into account the likely unbundling of transportation. Horace Dediu has been a big proponent of unbundling and points out most trips are local and short. [side note: you really need to follow Horace as well as well as David Levinson if you have any interest in the future of ground transportation] It makes no economic or environment sense to use a two ton car, gas or electric, to make a three mile trip. While much of North America has saddled itself with legacy transportation infrastructure and little imagination of what is possible, change is coming to Europe and it seems likely the developing world will favor very inexpensive electric micromobility solutions. 

 

Back to peak oil. M. King Hubbert was a geophysicist with the Shell Oil Company in the 50s when he started looking at long term oil production predictions.  All tended to make use of variables that weren't well pinned down.  Hubbert's model was simple assuming once a discovery was made, production would increase exponentially as more resources and efficiencies are brought in. At some point a peak is reached and an exponential decline begins. The model can apply to any region, or groups of regions,  assuming all of the discoveries are taken into account.  It also assumes the impact of new technologies occurs at a constant rate.

 

On the extraction side the so-called Hubbert curve has accurately modeled many oil fields and regions - notably the US through about 2005.¹  When dramatic new technologies appear - like practical fracking, shale and tar sands production, and  computer guided drilling - you effectively add new sources.   It's an interesting resource mining curve that's been used in many areas outside of oil production.  Hopefully we'll move to a point where most extractable oil is left in the ground and oil exploration becomes a thing of the past. 

 

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¹ It may look like a Gaussian or Bell curve, but it doesn't die off as quickly.  It takes the form

 

 

when not keeping your cool is a virtue

Why are we paying someone to heat parts of our house we aren't in?

 

This was one of my Dad's  deep questions.  Two adults, two kids and three dogs in a small house subject to Montana winters. Cold snaps could be deep and long - a week or more with highs well below 0° F ( -18° C) weren't uncommon.  More impressive were the lows:  -30° F (-35°C) came at least once every Winter and record lows were below -40°.  Dressing for it was a necessary skill.  Inside the home my Dad controlled a powerful technology - the thermostat.

 

When people were around during daytime the thermostat was set to 62°.  The nighttime setting, from 9 PM until the first person got up at about 5:30AM,  was 55°   If people were out of the house  the setting was 52°.   As far as I could tell these were his fundamental constants.  Warm clothing, sweaters, quilts (my parents cheated and had an electric blanket)  made it comfortable and sometimes even too warm.  There was only one thermostat and a few areas of the house were always a bit colder or warmer.  The dogs found the warmest regions at dog level. They also had warm blankets that they'd drag around where needed.

 

Since then I've learned a bit about home heating.  Some of the best information on home energy measurements comes from England.  They found standard modern construction homes see seven to ten percent energy savings for each degree celsius drop between 15°  and 20° C .  Lowering the thermostat setting from 70°  to 61° (21° to 16° C) could translate to 30 to 40% reduction in your heating bill.  It could also make a serious impact in places facing severe gas shortages this coming Winter.  

 

There are other tricks.  A big key is to heat the people and not the airspace where they aren't.  We had a small, partly finished family room in the basement.  We were there a lot during the Winter as it was the warmest room in the house.  Four people and three dogs radiated body heat along with four 150 watt lamps in the ceiling and a small electric heater (pro tip -- if you have a male dog, don't put one of these on the floor).  My Dad had a tendency to drop the thermostat to nighttime levels when we were down there. Most of our books lived there and a long work bench allowed my sister and I to work on homework and hobbies.  There was a TV, but it didn't get used that much.  It's where we told stories.¹  In the Summer the warm rugs on the floor came up and the room was a naturally cool place to escape the heat of the un-airconditioned home.  

 

The English studies I came across note the average English home was heated to 13° C (55° F) in 1970 rising to 20° C by 2000.   Our house wasn't all that different from the average English house. 

 

There are many other tricks for saving energy - insulation, heat pumps and so on, but they won't happen in Europe before this Winter for most people.  Insulation, done improperly, can be a two edged sword.  Forced air heating, the most common type in the US, fills the house with heated air. Insulation keeps as much of the heat as possible inside.  The problem is that often the air is trapped inside.  Stale air can be unhealthy (VoCs, high CO₂ levels, etc.).  There's a simple technology that can help - in fact you needn't look farther than your nose.  Your nose is a heat exchanger.  Cold air comes in and is heated up without releasing much of your body heat when you exhale.  Most industrial buildings and some homes have heat exchangers - they're required by many building codes to keep super insulated homes healthy.  Something to look into if your place is heavily insulated.

 

Localized radiant heat allows you to circulate some air from the outside and still be comfortable - you're heating people rather than the air.  You've probably noticed Scrooge's chair,  in many adaptations of A Christmas Carol, has a high back curved sides.  These were common in the Victorian era.. sit in front of a fireplace and focus the warmth. People have experimented with heated chairs with good results - notably work at Berkeley in the past decade.²  (They also designed and tested cooled chairs for the Summer).  People who live on the Japanese island of Hokkaidō modify the short legged Japanese family tables by putting a blanket over them and a small heater underneath.  I've used one of these visiting a couple from Sapporo when they were living in NY and was amazed how well it worked in their otherwise chilly house.  Teenagers like them for other reasons when their parents aren't home.  

 

In short there are many paths to clever - no silver bullets, but a lot of silver buckshot.  Twenty or thirty percent conversation levels are quite realistic for many people.   I won't mention adventures in an unheated 15 foot trailer with three dogs at -25°F (my mother thought colder temperatures were dangerous)

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¹  Nordic families seemed to tell a lot of stories.  Our heritage isn't Nordic, but many of our neighbors were and some of that rubbed off on us. 

² Here's an example and test of a heated/cooled chair. You could make one of these.. I haven't seen anything commercial.

 

 

 

inspirational chindōgu

Every now and again someone asks for advice on educational toys, projects or activities for their kids.  For a number of reasons I'm precisely the wrong person to recommend this or that.  It's not that I don't care .. I worry a lot about kids who enjoy math and science until they're 11 or 13 and then suddenly it becomes hard and boring.  This seems to happen to girls more than boys, which is just wrong.  Too many programs  focus on the top ten percent  and too few on those who could use a different way of seeing things.  I'm not terribly interested in the number of STEM graduates from college.  Rather, it's far more important having a literate society.

 

There are a few excellent motivators on YouTube.  Physics Girl is great, but her level is high school and beyond. For preteen and teenage girls (and many others) Simone Giertz is great.  She's a bit nutty, hyper-enthusiastic and has built a good business inventing useless things.  (She's also Swedish.  I defy you to find that in her accent.) Many of her projects are too advanced for a 13 year old to recreate, but the basics are there and recreating them isn't the point.  She wants to make you think about mechanical things differently.  She fires imagination with her humor.  Finally a huge bonus is that she admits to and highlights her mistakes.

Here's her latest - musical bubblewrap 

 

31 is the new 35

Andrew Revkin and I had a brief exchange about the power of labels.  Both of us object to the phrase "climate emergency."  Even though it is an emergency that could escalate into an existential threat, people don't respond to labeling longer term threats as emergencies.  I've been suggesting we've entered an adaptation epoch.  Andrew, a much better communicator, is still searching.

 

The past two or three years have taught us short term temperature excursions can be dramatic.  Last year the Pacific Northwest recorded previously unheard of temperatures -  the highest in the area in at least 7,000 years and probably much longer.  This Spring it was South Asia.  Last week record heat came to England and parts of Europe.  These events are probably going to be more common and time goes on and greenhouse gas levels continue increasing. 

 

Wet bulb readings of 35°C (95°F at 100% humidity)  have long been considered unsurvivable.  A person in good physical shape would probably die in a few hours. Such events are extremely rare. Until the past decade they've only been recorded a few times and then only for an hour or so.  They're increasing in frequency and length - mostly in the Indian subcontinent.  Finding cooler spaces for people is a matter of life and death.  

 

It's become clear the 35° number was something of a guess.  Recent careful work shows it's more like 31° for young people in good physical shape.   Older and compromised people have lower limits.  The Tokyo Olympics had periods with wet-bulb temperatures in the upper twenties. Athletic performance during these periods was certainly compromised (I saw it happen to a friend). 

 

What can be done?  Cities suffer from heat island effects.  All of the asphalt and concrete increases the local daytime temperature and holds them at higher levels at night. (hot nights may be harder on the body than hot days).  Air conditioning helps, but it costs money and a power grid that not everyone has access to.  Reducing the amount of asphalt and concrete while planting trees can make a big difference.  It's a great justification for reducing the number of cars and roadways in cities (green spaces are a key motivating reason for the dramatic change currently underway in Paris).  Unfortunately green spaces are usually linked to wealth.  In many places racism and redlining have produced some of the worst heat islands.

 

There are other tricks that are easily implemented.  White paint  on roofs can make a difference. Paint that holds up to temperature and monsoons for the better part of a decade isn't cheap, but is becoming more popular.  In Western countries more reflective shingles are appearing. Some of these look fairly normal, but are highly reflective in the infrared and can make a difference in cooling bills. 

 

And you can send some of the excess heat directly to space.  

 

If you're in a very dry area go outside on a clear night and look up.  Feel the cooling on your face.  Now hold a piece of cardboard between your face and the stars.  You'll notice a warmer feeling.  Remove the cardboard and your face gets cooler. 

 

Your body glows - you've undoubtedly seen infrared photos and videos of people.  We radiate photons at a variety of wavelengths, but it peaks around 9.5 microns - about twenty times longer than visible light.  The  atmosphere is transparent to visible light and also from 8 to 13 microns.  Photons from our bodies can radiate to space.   Deep space is really cold (a bit over 2° above absolute zero) so your face is radiating some of it's heat directly to space - enough that you can feel the cooling.

 

Clever material engineering has produced materials that are good at absorbing the heat around them and then radiating it into space. It's enough to reduce cooling requirements - at least in places with very dry atmospheres.  There's still work lowering costs and making the surfaces last longer, but it's something else to try.

 

Back to the idea of an adaptation epoch. Many things will need to be tried and efforts will stretch for generations.  There's enormous opportunity.  It's both sad and dangerous there's so much 19^th century political inertia, but I'm optimistic more clever people, organizations and governments will finally emerge.  As a species we don't have a choice if we want to survive.

 

repairability

My Dad was a Ford man.  More specifically the Ford Falcon.  It was a simple compact car with a 170 cubic inch displacement straight six coupled to a three speed manual transmission.  It scored on the high end of the Mobil fuel economy test - about 19 miles per gallon when the average sedan was in the 12 to 14 range.   But what he really liked about it was how repairable it was.  Not only was it simple to work on, but most of his friends had cars with the same engine and transmission.  If something needed fixing we could usually do it ourselves using tools borrowed from one of his friends.  For more serious repairs there were specialized tools from Strobel's A to Z Rental, garages or (shudder) the Ford dealer.

 

The simplicity of cars of the day was balanced by crude manufacturing tolerances.  Pistons fit so poorly in the cylinders that the first 500 or 1000 miles were done with great care using an abrasive oil to polish the parts into shape.  It made a big difference in gas mileage and extending the life of the engine past 50,000 miles.  

 

The dual gas shocks of the 70s opened the market for better cars that used higher precision design and manufacturing processes.  That and the beginnings of cars that crumpled to absorb energy in crashes made simple repair much more difficult.  The amateur mechanic had largely vanished by the 80s.

 

Clothing and shoes were expensive back then.  Quality construction and repairability were important considerations while shopping.  Tailors and dress makers were common.  The same was true for appliances.  Vacuum cleaners, toasters and anything electronic could be repaired at home or the local repair shop. 

 

There are exceptions today .. Jheri makes her own clothing or buys high quality pieces with the intention of buying very little as she hopes each piece will last at least a decade.  She's abandoned fashion and has created a style very much her own.  I suspect some of you - Om for example - have a similar philosophy.    But while it can be done in clothing, it's next to impossible when electronics are involved.

 

By the time I was fourteen I had three or four black and white TVs.  None of them worked - watching TV wasn't interesting.  The tubes, capacitors, transformers, switches and so on..  now those were useful!  I designed and built a few radios and a stereo amplifier.   It was straightforward and the experience taught me a lot about electronics.  Now I look in a computer, TV or radio and see only massive integration.  It's still possible to build things, but design is much more difficult. Learning about circuit elements is probably better done with computer simulations.   

 

The right to repair movement has grown in recent years.  I welcome  it for some products, but given the tight integration of hardware and software  I worry it may not be as generally attractive as proponents claim.  

 

Smartphones are a case in point. Apple is infamous for discouraging third party repair.  You can order a kit from Ifixit to replace a screen, battery and some other parts.  It can work well if you have a bit of experience and Ifitit is upfront with the degree of difficultly. You lack the tools and technique to take apart, replace and reassemble the device to design specifications.  

 

My personal results are mixed.  I easily replaced the battery (twice!) on my first day, first generation iPod.  The battery and screen on my out of warranty iPhone 5 was a different matter.   After five hours of frustration I was left with an operating phone, but the case was fitting tightly and whatever waterproofness was gone.   The misaligned case also interfered with the physical buttons on the side.  I did get another year and a half from the phone though.   It could be worse.  I know someone who replaced the battery on an Android phone with an inexpensive battery from Amazon.  The phone got very hot during charging and caught on fire when he took it apart to pull the battery out.  It filled his place with acrid smoke, but fortunately only destroyed the phone and wastebasket

 

Apple is afraid of regulation so they offer repair kits for some of their devices.   The Verge documented a battery replacement.  You get a huge repair kit with a large hold on your credit card until Apple gets the kit back.  The process probably works well if you're skilled at working with small electronic devices, but this isn't for everyone. Given the cost of shipping I suspect Apple's losing money, but they're also trying to make a point of what it takes to do a high quality repair.  Of course a third party repair shop could buy the tools and perform quality repairs and I suspect that will happen.  Lower quality shops abound, but your phone or laptop may be a bit wonky afterwards.

 

We need to understand what's repairable, what's sort of repairable, and what's not.  Easy to repair smartphones have been offered but they're generally expensive and lacking in features.  I suspect smartphones, laptops and smartwatches are probably moving to a subscription model anyway.  Clothing and some appliances could made for longer lifetimes and repairability.  Then again convincing consumers and companies to move away from a consumption model is a huge, but very important, challenge. 

 

I've mentioned clothing, but should follow-up with other product areas where design for long life, repairability and upgrading is important. It's generally expensive, but in the long run can have advantages.  You may live in an example.