omenti

heat and the paris games

It's wrong to hold a Summer Olympics in Tokyo in late July through early August. The right time for the Summer Games in many climates would be the Fall, but television schedules force the Summer.  The combination of temperature and humidity can be dangerous.  Endurance events, tennis and beach volleyball take place outdoors and can place athletes and spectators at risk. With Covid Tokyo didn't risk spectators as there weren't any, but some of the events took place in borderline insane conditions.  The top Canadian team played one of their matches with a wet bulb globe temperature of about 40° C.¹  Sarah texted photos of herself sitting in baths of ice water to bring her core temperature down to safe levels.  Four hours at 35° C is considered potentially lethal for a young person in good physical shape.  A new standard suggests the limit for any outdoor activity should be about 32° for this cohort and 28°C for anyone over 60, under 8,  or anyone with any number of medical conditions  

 

There is a good chance Paris could be worse this year.  The Olympic Village is not air conditioned.  To meet certain green goals it uses passive geothermal cooling, which is great, but doesn't work well in extreme conditions.  Team USA, Canada, Australia and probably many others will install portable air conditioners in athlete housing and indoor training rooms.  Spectators are on their own.  Paris is not a heat-friendly city. 

 

When you do any kind of physical work like staying alive or exercising, about eighty percent of the energy you take in is converted to heat.  Some of that raising your body temperature above the environment around you, the rest is waste heat.  A moderately fast bike ride can require about 200 watts so you have 800 watts of waste heat that has to go somewhere. Sarah, in an intense match, averages about hour hundred watts with higher peaks.  She has to get rid of two kilowatts.  Evaporating liquid water takes quite a bit of energy and our bodies are wonderfully set up to do this.  Sweat is your friend.  It works well in dry heat, but becomes more difficult as the humidity goes up and impossible when the the wet bulb temperature is above a certain value (in fact trying to use a fan can make matters worse).  

 

One can imagine an event being postposed due to extreme conditions, but the fact that Tokyo had events suggests training your body to sweat better -  heat conditioning - makes sense.  You can become a better sweaters by making your body to handle electrolytes differently, sweating earlier and more, having more dilute sweat and a few other biochemical tricks that enhance your ability to deal with the heat.  One  can train in hot and humid areas - places like the American Southeast and parts of Southeast Asia and South Asia.   That's not practical for many and  not controllable so other techniques have emerged.  Some use a stationary bike in a heated chamber, but sauna therapy works as well or better.  You sit in a 80° to 90°C sauna for about 45 minutes in 15 minute shifts with 15 minute breaks every day for about two weeks.  After that you can maintain an enhanced level doing this two or three times a week.  Not fun, but it works.   In some events medals may well be decided by who has had better heat preparation.

 

Much of the rest of the world is on its own dealing with heat.  Some are suggesting air conditioning should be a human right.  To say there are major challenges is an understatement - one that the first world mostly ignores and will probably continue to ignore until events like two or three day power outages turn off AC in heatwaves.

 

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¹ A wet bulb globe temperature is more detailed than a heat index or "feels like" temperature.  It takes into account temperature, humidity, water evaporation and sun exposure. Calibrated instruments start at around $500 and go up so it's generally not reported.  Standard "feels like" temperature is an ok starting point and much better than regular temperature for decision making.

 

some surprises

About 35 years ago well drillers came to the Bourakébougou in Mali in an attempt to find the water table so the village could enjoy a more reliable source of fresh water.   They had given up on a dry hole when one of the drillers felt a breeze coming out of it. Peering in, he discovered smoking can be bad for your health.  The explosion and fire didn't kill him, but left him with painful burns.  The fire burned for weeks without smoke and was bright enough to light up many of the surrounding fields at night.   Weeks passed before the well was finally capped.  

 

About twenty years ago an African oil company bought the rights to the area thinking it must be some kind of natural gas deposit.  That turned out to be partly correct.  Analysis showed the gas was 98% hydrogen. That, of course, seened impossible.  Hydrogen is rarely associated with fossil fuel deposits.  It didn't seem like enough for viable production at the time, but an old car engine was modified to run on hydrogen.  It turned a small generator which produced electricity for lighting the village.  The head of the oil company started Hydroma with the goal of finding profitable hydrogen wells.

 

You've probably seen hydrogen associated with a variety of colors.  Brown and black hydrogen is produced by coal gasification and results in the emission of large amounts of carbon dioxide.  Grey hydrogen is made from natural gas using a steam reforming process that currently releases large amounts of carbon dioxide into the atmosphere.  Very dirty, but inexpensive and common ways to produce a clean burning gas.  Blue hydrogen is essentially grey hydrogen where most of the carbon dioxide is captured and stored.  Green hydrogen is produced using the technique you probably used in school when you were eight or nine - electrolysis.   It can be used as a storage mechanism for intermittent "green" power sources like wind and solar. There are a few other colors made from more obscure techniques, but the common thread is each technique recognizes that hydrogen is bound to some unrelated molecule and has to be split off.  Think of it was a battery of sorts.

 

There's a lot of hydrogen in the Universe - about 90% of regular matter or about 75% by mass. About 62% of the atoms that make up you - 9.5% by mass - happen to be hydrogen. When the Earth was formed, the gravitational pull wasn't strong enough to capture and hold any molecular hydrogen in the vicinity.  It had been assumed that small pockets could be trapped in the Earth, but these would be small. Bourakébougou was viewed as an unlikely exception.  It seemed likely hydrogen was produced in certain iron-rich rocks in the upper mantle where the temperature could be high enough to release hydrogen.¹  Entirely different locations than where one finds fossil fuels and therefore poorly explored.  

 

A few new mines have been found and characterized.  So far they're modest in size.  Current hydrogen demand is on the order of 100 million tons a year and these deposits are more on the order of tens of thousands of tons.   But recently geologists have projected the possibility of much larger amounts.  It isn't clear how much would be reachable or the cost, but there's excitement in what's being called gold hydrogen.

 

As a fuel, and gold hydrogen is a fuel, hydrogen has advantages and disadvantages.  Although hydrogen's energy density per unit mass is high, its  volumetric energy density is low making it impractical for current aviation technology.  It seems more useful for large transport - long distance trucks and ships as well as power plants, but green hydrogen as a battery may be more cost effective as well as being a natural battery for intermittent green energy sources.  Time will tell.   Gold hydrogen in potentially commercial quantities came as a surprise to me. 

 

The Universe is peppered with gravitationally assembled hydrogen fusion power plants - our Sun being the most familiar.  We use only the tiniest amount of the power that falls on the Earth and that, in turn, is only a tiny fraction of the star's power output. It's a question of capture, conversion and transmission.  We know how to do many of those things, but..

 

If you're lucky enough to be in the path of totality of the North American solar eclipse in about six weeks you might get a sense of the Sun's activity.  Up close it's much more dramatic. Here's a nice video showing 11 days looking out from a side mounted camera on the Parker Solar Probe - part of a mission of highly elliptical orbits that get closer and closer to the Sun.  A few months ago it came with 7.26 million kilometers of the Sun's surface and was trucking along at over 635,000 kilometers per hour at perigee - far and away the fastest probe humans have made. (it takes much more energy to move towards the Sun than away from it)   The video flies through a coronal mass ejection..  it's amazing stuff! (while I'm a fan of Beethoven, I think this is better appreciated without the music)

And finally the Seagull Nebula - a nearby cloud of mostly hydrogen.  It's too dim for our eyes, but is close enough to appear large in the sky.  It was one of the first things I looked for with the telescope I made as a teenager.  To see its real spender you need very long exposures - something unavailable to me in the day.  APOD is a wonderful site. 

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¹ There are a half dozen potential mechanisms.  This one, involving the mineral olivine, has been observed and is likely to be the most important.

 

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.

 

 

 

not buying it yet

Extraordinary claims require extraordinary evidence

    Carl Sagan - Cosmos

Several people have been in contact with questions about a new physics paper on a room temperature superconductor. It’s a big thing it’s real and if it can be developed into something practical. I skimmed the paper at first and then gave a more careful read. So here are a few early comments.

 

First the background. Superconductors conduct electricity without resistance, but there are caveats. The most useful ones need to be cooled to liquid helium temperatures. At normal atmosphere pressures that’s about 4.2 K .. really cold! (absolute zero is 0 K). Helium is very expensive, in short supply if you want scale and expensive to liquify and keep in a liquid state. LHe temperature superconductors are used in superconducting magnets that produce very high magnetic fields - physics experiments, maglev vehicles and MRI machines are major users. For the last 25 years or so we’ve had superconductors that work at liquid nitrogen temperatures. LN₂ is comparatively inexpensive and fairly easy to handle. The problem is they don’t support high electric currents or magnetic fields.. There’s been a lot of focused research working on this with the best materials known as ReBCO (rare earth barium copper oxides) - there’s a largish family. They do support relatively high current densities and magnetic fields at liquid hydrogen temperatures. LH₂ is between LHe and LN₂ in temperature. It’s much cheaper than liquid helium. Currently the cost of LH₂ temperature superconductors is about four times that of conventional materials in high field magnets. Getting down to the same cost would be a big thing.

 

There has been work on much higher temperature superconductors - some work suggested it could be done at room temperature, but at very high pressures. That was a couple of years ago, but there are questions with the experimental work and the very high pressure requirement makes it impractical. But if it turns out to be real, it could provide useful insight.

 

So onto the current paper. It shows superconductivity at and somewhat above room temperature (up to 400 K!) and at sea level pressures.

 

Reading the paper I see a number of red flags. It hasn't been peer reviewed yet.  None of the authors is known in the field and they’re from an institute that doesn’t have a track record. Important discoveries are sometimes made outside of the field, but it’s VERY rare. They talk about critical (magnetic) field and critical current. Both numbers are extremely low - far too low to be practical. Also critical current doesn’t mean anything .. the right metic is critical current density. It’s not a typo .. their graph shows current rather than current density. More troubling is they don’t find a Tc (critical temperature).. they only state it’s still superconducting at 400 K. The fact they can’t make it go away raises red flags.

 

You also need to demonstrate the Meisner effect - the exclusion of magnetic fields - it gets technical, so I won’t go into details, but just noticing a drop in resistance isn’t enough. They do claim a Meisner effect, but their graph doesn’t show it. It looks like garden variety diamagnetism.

 

There are a few other technical issues, but I think I've made my point.

 

They offer a theory of what’s going on, but it’s ad hoc-ish. That’s not really a problem - an experimental result doesn’t need a theory. But why do they try? red flag.

 

It should be easy to replicate. Their technique strikes me as sloppy. It’s possible they’ve discovered something. We’ll know quickly as this should be straightforward to try and replicate. If it’s real and the magnetic field is what they show, it isn’t practical.  It would offer a window into a different class of materials to try.

 

For now, color me skeptical. Extraordinary claims require extraordinary evidence. They don’t offer much in the way of evidence. I worry we have another Pons and Fleishmann paper.  A big sin was P-F publicly claimed they had made a fusion breakthrough with cold fusion and the media jumped onto it. At least these guys don’t seem to be banging the publicity drum.

 

LH₂ class superconductors may be very practical for many commercial applications in the next five to ten years. That’s a very important area that could become commercial soon. It would be even better if it can work at LN₂ temperatures, but so far it’s been disappointing.

 

magnets and a most dramatic moment

The opening ceremony of each Olympic game is filled with pageantry and sometimes, with the lighting of the cauldron, drama.  In my mind the most electrifying occured in the 1992 Barcelona games when Paralympian Antonio Rebollo performed some serious diablerie. 

Across the ocean in New Providence, New Jersey David and Mary watched the scene on a small black and white television as they shared pedaling duties.  David was pedaling at the time and gasped.  Fortunately there was a flywheel.

 

Their parents didn't allow television in the home, but both of them had been involved in competitive kayak and canoe events.  Lynn had been an alternate for the Montreal Olympics.  Introducing Mary and David to the Olympics was a good idea, but Al decided to make it educational. The kids would be given an exercise bike, a generator, access to a television and help from their mechanical engineer father and mathematician mother.  They had a few weeks to work things out.

 

When the the friction wheel generator was finally adjusted and working, they were shown how much power they produced and how much power various televisions used.  A twelve year old could keep a small color set going for a short time, but that was it.  They wisely chose the black and white set.  Through trial and error they ended up with a bicycle chain transmission and abandoned the exercise bike for one of their own on a homemade stand. They could now produce nearly twice the power for the same amount of perceived work.  A flywheel was added to make everything smoother.   They had something by the opening ceremony and the kids spelled each other off and developed an amazing sense of how long the commercials lasted.  They saw the torch lighting.¹

 

It's too bad they had a standard generator.  Something with better magnets would have had increased efficiency.  Not enough to move them into a color set (if they were a few years older and more athletic they probably could have managed), but certainly a better experience.  The strength of the magnetic field in a generator or motor is centrally important.  The strongest fields come from superconducting magnets, but they need to be cooled to near absolute zero rendering them impractical for most applications.

 

Electric vehicles use either induction or permanent magnet motors.  The permanent magnet designs tend to be lighter and are more efficient.²   There's a rub.  You're trying to optimize cost and magnetic field strength (among other things).  Rare earths like neodymium work much better than the cheaper ferrite-based magnets and have generally taken over the medium and high end automotive market.³ 

 

The problem with rare earth materials isn't that they're rare .. they fairly comment.  They are, however, unevenly distributed and difficult and toxic to mine and process.  Most of the active mining and processing is in China and it's an environmental disaster.  The US had a single mine in California in the fifties.  Since then it's had t an up and down existence including being closed for economic and environmental reasons.  With the interest in EVs it's back in operation again  and the US has gone from 0% of the world's production of neodymium to about 15% in about seven years.  In theory the mining and processing and safer and less toxic than the Chinese effort. Production should increase in the future.  The US is also largely unexplored - serious mineral exploration has only just resumed after a 60 year hiatus. 

 

The higher cost has some companies, notably Tesla, talking about going to ferrite permanent magnets.  They'd be heavier, less efficient, but would be cheaper and may be the core of lower-end vehicles.  Another alternative is to use a more efficient vehicle.  Electric bicycles and other micromobility solutions use small motors.  You can build 50 to 200 electric bike motors with the materials from one Tesla-class motor.  Not only that these vehicles are very practical for the short trips that dominate much of our mobility needs.  Sadly some areas have saddled themselves with transportation infrastructures that encourage inefficiency.

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¹ Mary continued in the families sport tradition and went to Princeton on a fencing scholarship.  She found she was interested in aeronautical engineering and went on for a Ph.D.  I heard she had something to do with the rotor design on the Ingenuity helicopter currently flying on Mars. 

² There are often questions about how permanent magnets work.  Most people have seen electromagnetic induction in school.  A current flows if you move a magnet in a coil of wire and a current through a wire produces a magnetic field.  Permanent magnets are more difficult to talk about .. I've done it at least once, but this short video is a nice intro.

 

³ There are other rare-earth based magnets, but a neodymium alloy is the most common.  It's an allow of neodymium, iron and boron - Nd₂Fe₁₄B - that forms a crystalline structure.  They have widespread use outside of EVs.. GM and Sumitomo Metals independently developed them about 40 years ago to get away from much more expensive and brittle samarium–cobalt magnets.

There's a lot of talk about tetrataenite (an iron-nickel structure) permanent magnets.  In theory they have better magnetic characteristics than neodymium alloys and should be much cheaper, but they're off in the future.  If they happen, expect some unhappy rare earth mining companies. 

 

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

 

 

unexpected arcs

Three weeks ago breathless reports on the 'breakeven' fusion event at the National Ignition Facility began to appear.  While a remarkable achievement, it's more a marker of progress along a long and difficult path rather than an event promising a hopeful turn in decarbonizing the energy supply. 

 

Nuclear fusion has been hyped since the late 1950s.  Fission based reactors turned out to be straightforward.  All you had to do was refine uranium ore and then control a reaction to heat water and run an otherwise conventional power plant.  The cold war led to any number of atoms for peace projects suggesting a nuclear everything future.  The realization that nuclear fusion was much more efficient and "cleaner" than fission led to optimism and work on controlled fusion.  After all, it happens all the time in stars doesn't it?

 

Power from nuclear fusion has been twenty years in the future ever since.   Science and technology have made serious progress, but the challenges are great.  There's also the issue of cost per kilowatt-hour. If you build a plant that produces more power than it takes to run it, will it be economically competitive with other low or no-carbon solutions? 

 

There's a simple invention → development → application → change arc of technology mindset that doesn't describe the real world. It turns out you can travel a good distance along the arc only to see failure.  The garage-worthy helicopter, supersonic airliners and dirigibles have all be built and commercialized, but have failed for a number of reasons that are likely to keep new versions failing for the foreseeable future.  Somehow the dream factor persists in many of these and new failures continue to rhyme.

 

There are hugely successful inventions that have solved a problem, but turn out to have a deadly flaw that caused great harm.  DDT,  chlorofluorocarbons and leaded gasoline are obvious examples.  Less obvious are inefficient transportation.  Standardizing on 3,500+ pound vehicles to move people a handful of miles on average trips has led to millions of traffic deaths, a large pollution toll and a structuring of infrastructure and where and how people live that is proving difficult to change even though much better choices exist.  Sometimes tend to fire, aim and then look for damage around the target.  Sometimes it takes decades and change is expensive. 

 

There are a wishlist class of inventions where some progress is made, but effective deployment is a long way off (fusion power plants)  or unlikely as the underlying approaches are flawed at this point (self-driving cars, hyperloops, neural implants, space elevators, nuclear powered cars and airplanes, etc.)

 

It's very easy for an imaginative artist or writer to sketch an idea that is technically impossible.  We have a tendency to sort through the chaff and find amazing predictions from a hundred years ago.  It's useful to realize how much noise there is and that these things didn't happen in the author's or their children's lifetimes.  Still - every now and again you run across something that stops you.  This is one of my favorites - not only because it suggests wireless video communications, but it also nails the social element of two people ignoring each other so they can look at a screen.

 

Then there's a class of necessary arcs that we need to get past application and into wide-spread use.  Flexible power distribution to move power from generation to where it can be stored or used.  An advanced worldwide pandemic monitoring system.  Water management and treatment to deal with changing local climates as well as use needs.  More efficient agriculture that can deal with changing climates.  Changes to transportation and housing infrastructures that are less damaging.  Some of these aren't terribly sexy, but require social and political will - areas where progress is often very difficult.  And in the background there needs to be investment in fundamental science.  While progress can be difficult to predict, historically it's easy to predict that there will be unexpected discovery that can lead to something useful down the road.

 

It's fun to enjoy the stories writers and artists weave.  Creating your own is a great way to work with the imagination of a nine year old on a rainy day. Time and interstellar travel won't come along with scores of other ideas that help move stories along.  

 

 

fusion!

The short version is it’s a remarkable technical and scientific achievement. Controlled human-made power from fission is easy - last week marked the 80th anniversary of the first reactor. Fusion - what powers the stars - is much more difficult on Earth. The necessary temperatures are far greater than those found in most stars. A star like the Sun gets away with a very slow and low power density reaction that would be impractical for generating power on Earth. It turns out the power density of the core of the Sun is about a quarter of your metabolic density and close to that of a lizard. To get around this different fuels are needed along with much higher temperatures. Still, if you can only figure it out, it sounds like the perfect goal - fuel from water and no radioactive waste.

 

The first serious attempt at magnetic confinement look place about 60 years ago .. it, along with every other effect until this last week failed. Those that achieved fusion required more input power than the power they produced. The figure of merit is Q: the ratio of the power of the fusion reaction divided by the power required to ignite and sustain it.

 

The laser confinement experiment announced focused a short pulse of light - about a billionth of a second - from 192 lasers onto a small gold container that vaporized to generate x-rays that collapsed a diamond coated fuel pellet of deuterium and tritium. The power of the laser light was 2.05 MJ (megajoules — a gallon of gasoline is 121 MJ, a hot dog in a bun is about 1.5 MJ) and the fusion explosion yielded 3.15 MJ. A Q of about 1.5. What isn’t mentioned is the efficiency of the lasers or the facility isn’t included - or the efficiency of extraction power from the miniblast. The lasers are less than one percent efficient so you can see there’s a long way to go.

 

This facility has been running for about a dozen years. It has been solving enormous engineering and applied science problems along the way as well as contributing to the pure science of understanding plasmas at this scale and temperature. Even the fuel pellets are very difficult to make and test. They have to be extraordinary symmetrical and most are rejected in testing - usable pellets are very expensive.  What has been achieved is not a prototype, but rather a triumph of instrumentation technology along with the control of some difficult to manage parameters. 

 

Moving this line of fusion forward seems like a long shot. A factor of five improvement may be possible with a redesign, but they need more than a thousand. Not impossible, but there’s a long path ahead.

 

There are other design types that confine microwave heated plasmas. Getting it right and working will take many years - probably decades and then there’s the issue of what does a facility cost compared to other types of power stations.

 

I hope work goes forward, but not at the cost of workable technologies that address global warming *now*. There’s so much that can be done, but very little political will.

 

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.

 

 

 

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.