Plowboy Interview: Harold R. Hay Talks About Solar Energy

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The Hay Sky-Therm house in Atascadero, California. Its innovative solar design includes rooftop insulating panels and bags of water used for passive cooling.
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Harold R. Hay, solar energy pioneer.

Steve Baer (developer of the drum wall, beadwall, skylid,and other solar hardware that works) often tells about someof the first meetings he attended of the International SolarEnergy Society and other “official “solar organizations.

“Everybody there would be talking about sophisticatedcollectors and tracking systems and very exotic and expensive surfaces that were marginally more efficient absorbers ofthe suns rays and multi-million-dollar research projects,”says Steve.And, usually, the guys doing all the talkingdidn’t have a working prototype of anything they werespouting off about.

“And then Harold Hay would get up and he’d have someactual test data taken from some incredibly simple and lowcost experiment he’d just ran. And everybody would say,‘You mean that’s all you’re doing? You’re just moving someinsulation back and fourth? And they’d all go back to theirdiscussion of some idiotic idea that would probably neverwork–but which was sure to cost the taxpayers of, thiscountry several million dollars. They just couldn’t appreciatethe genius of the man.”

Genius indeed. And in far more than the field of solar energy For during his life Harold R. Hay has been–at various times–a political reformer, the developer of what is probably, the world’s most widely used wood preservative, the originator ofan internationally recognized municipal water purification treatment, the head of several private research projects, a U.S. Government agency’s official International Building Materials Advisor, and many other things. And always–and above all–Hay has been His Own Manwhich is a rather forgotten skill in this age of conformity.

Still, it’s Mr. Hay’s work with solar energy for which he is currently best known. As well he should be. For the Hay Sky-Therm system of heating and cooling a house works the way a solar heating/cooling system should work: with no pumps, no fans, no circulating liquids, no freezeups, no boil-overs, no trouble, no noise, no dirt.

And this is no mere theory. Harold Hay built his first passive solar heating/cooling system into a house in India 20 years ago. Ten years later–on Arizona property owned by another solar pioneer (John Yellott)–he constructed and exhaustively tested a much improved version of the original idea. In 1973, yet another experimental Hay solar house was built and evaluated in Atascadero, California. And, at last count, at least 21 other Sky-Therm houses were under construction in various parts of the United States.

Can it be that the rest of the world is, at last, catching up with Harold Hay? Perhaps. Then again, you should know that the following interview was originally taped over two and a half years ago. And it contains such tidbits as the Hay theory of “cool black and warm white”.. . which, I’m sure, most “authorities ” on the subject are still at least 20 years from accepting.

Mr. Hay, we always like to start at the beginning with these things … so let’s do that, if you don’t mind. Where and when were you born ?

I was born in 1909 in Spokane, Washington. Most people today think of the city by its Chamber of Commerce designation, “Hub of the Inland Empire” or “Capital of the Inland Empire” . . . something of that nature. But, to me, it’s always been Spokane … derived from the Salish Indian word, spokanee, which means “sun”. “City of the Sun”. That’s the way I always think of my home town … and maybe that’s influenced my life’s work just a little bit.

Well you’ve certainly become known for your involvement with the sun. Did you originally set out to be a solar energy pioneer?

No, I went to the University of Wisconsin to study chemistry and found myself taking an extremely interdisciplinary course. Before I knew it I was minoring in biology, botany, plant physiology, plant pathology, bacteriology, and even engineering.

I found this all very stimulating. So stimulating, in fact, that–while still in my freshman year–I came up with the concept of preserving wood by mixing sodium silicate and an acid to get a precipitate of silic acid. My idea, you see, was to impregnate wood with the two solutions to get a precipitate that would make the wood fireproof and decayproof … “petrified”, if you will.

When I took this concept over to the U.S. Forest Products Laboratory, I was lucky enough to talk to a man who was really an extraordinary teacher. He already knew that the idea had been patented in 1860 but he didn’t tell me that. He just asked if I’d researched all the previous work in the field. When I answered that I hadn’t, he said, “Well, you go over to the library and start digging into the patents that might have a similarity to this idea of yours, and we’ll give you some help whenever you need it.”

Eventually, of course, I did find the 1860 patent for “my” idea and–as might be expected–I was kind of disappointed … especially when I learned that the concept hadn’t worked as well as expected. But my mentor just said, “Go on. Study further. Maybe you’ll be able to solve the problems that stumped your predecessor.”

So I did go on. And the next year I came up with another idea that my guide thought was very good. I combined some of the things I had learned in plant pathology with some known facts about wood preservatives and came up with a way to make the fungi that attacked wood, in effect, commit suicide with their own secretions. My advisor over in the Forest Products Lab liked that and asked me what I’d need to develop the concept. And I told him and he suggested that I get in touch with my professor and there I was–a sophomore–given the keys to the chemistry building! As a result, I’ve been in research ever since.

Yes, but there’s research and there’s research. There’s the “white coat in the lab” type and there’s the “get your hands dirty in the field” kind. Which variety have you specialized in?

I’ve been lucky. I’ve gotten to do it all. On that first project, for instance, I was responsible for everything. I prepared the logs, went through the sawmill with them, took the samples, conditioned the wood, made all the physical tests and the microscopic examinations, and analyzed the changes that took place in the wood we treated.

This was extremely valuable training, you see, because gave me a very interdisciplinary approach to looking at problems. As did my library research the year before, when I had studied the original work done by both scientific and technical people and other experimenters who hadn’t been so scientifically and technically trained.

As a result, I’ve never been particularly disturbed about going into some “expert’s” carefully guarded little area of expertise and doing something. Also, as a result, I became comfortable doing things with my own two hands. I wasn’t relying on an assistant–who might or might not know what he was doing–to handle my dirty work. I wasdoing it my self. I was developing both the theory and the shop experience on my own as I went along. When an experiment fell on its face, I knew I was the only one to blame . . . and when something went right, I knew exactly why it turned out OK because I had done it.

I think this personal involvement–this “hands on” approach to research–is a very important part of finding the solution to a problem. It’s a shame that so many of today’s “big names” in so many fields relegate this so-called “dirty work” to assistants. Perhaps that’s why a great many of the current “experts” in almost any given field can so blandly make the most outrageous and conflicting statements about their areas of study.

You read the papers written by these fellows and you realize they’re contradicting each other and you say, “Gosh, they both can’t be right.” And then you analyze the situation from first one and then the other’s point of view, and you sometimes wind up finding them both wrong. They’ve each gotten an idea and then spent so much time justifying their respective positions, that they’re both completely blind to a third–and the actual–answer to their problem. They’re out of touch with the real world. They need to theorize less and just roll up their sleeves and actually try some of those grand ideas they’re kicking back and forth. You can argue all day about theories … but, once you put them to the test, they either work or they don’t. And there’s no arguing about that.

What about your wood preservation ideas? Did they work?

I continued them through college–I graduated in 1932–and on until ’34 with a little graduate work on my scholarship. We had a pretty good depression going on then, though, as you’ll recall … so I dropped out of school a year ahead of a Ph.D. I had an offer from the Monsanto Chemical Company in St. Louis to evaluate a line of products and I said I’d do it if the firm would manufacture pentachlorophenol as a wood preservative.

Well, the people at Monsanto told me there was a little conflict of opinion in the literature about that product: some said it was good and some said it was bad, So I went to work for the company and tested pentachlorophenol for three or four months–I was given the right to do so–and I proved that it was a very good product for the preservation of wood. It’s now produced throughout the world and it’s saved tremendous amounts of lumber from decay and termite damage, which means that we have to cut less trees to keep us supplied with wood–in that sense, it’s a very ecologically sound contribution to man’s technology–and it probably will not be replaced for that purpose in the foreseeable future.

So, within months after taking your first job you made a major breakthrough for a large firm. I suppose that secured your future with Monsanto for as long as you wanted to stay there.

Possibly so. But once I had solved that problem there didn’t seem to be much purpose in sticking around. I grew restless and started looking for something new to test myself on.

Something in chemistry?

No, right at that time I had gotten a little perturbed at the political situation in St. Louis. Gangsters had control of the city and there was corruption from one end of town to the other and I didn’t like it. So I thought I’d just change things around. My roommate said, “You don’t think you–one lone individual–can do anything about the whole political machine of St. Louis, do you?” And I said, “You’re darned right I can.” And I did.

I left Monsanto and it took me about a year and a half to consolidate what we called the “river rat” wards and then divide up the outlying wards of town to change the whole power base of City Hall. But I’ve never been a money raiser so, even though I got a lot of endorsements while I was doing this work, I didn’t have any income at all during the whole 18 months. I stayed alive by eating peanut butter sandwiches but I got the job done. Then, of course, I needed to earn some money, so I left St. Louis and went to work in New Orleans for the Celotex Corporation. A year and a half later–when the reforms in the city of St. Louis had been approved by an election–I got a telegram that ended, “Thanks for eating peanut butter.” That was the only pay I ever got for that work.

And what did you do for Celotex?

The company had been threatened with lawsuits over its use of arsenic in a wood preservative. It was my job to research about 150 years of medical literature–written in six different languages–to determine whether or not the claims against the firm had any merit. As it turned out, they didn’t. My research–and the tab experiments that grew out of it–reversed the whole 150 years’ worth of conclusions on the subject. When we presented my findings–that arsenic used as a wood preservative presented no toxic hazard–to a professor in the field, who happened to be the editor of a journal of tropical medicine, he published them. So one of the first things I ever published was in the field of medicine.

What did you do next at Celotex?

I walked out. They wanted to tell me what to work on and I couldn’t really get interested in the project so I went looking for one that I could get involved in. That was in Peoria, Illinois with the U.S. Department of Agriculture’s Northern Regional Products Laboratory. Then I went with Philadelphia Quartz, where I developed a water purification treatment that, environmentally speaking, was quite valuable at the time. The process cleaned up some of the mess made by industry and was good enough, at one time, to be used for 90% of all the municipal water in Florida. It’s still in use in many parts of the world, although it’s being replaced now in this country by an even simpler system.

And this was … when?

The early 40’s. During the war. And then the atomic bomb was dropped on Japan and I suddenly realized–as a chemist–the tremendous effect that the nuclear age would have upon the world. So I resigned, determined to move on to something that would no longer confine me to just the United States. I wanted to reach out, work with other nations, foster the cause of brotherhood,

I tried UNESCO, but that organization wasn’t ready–at the time–to accept any Americans. The bureaucrats at UNESCO gave me quite a runaround, just as bureaucrats in any big organization in any country always do. They get in the way and undercut you behind the scenes and you never know what’s really happening. It’s that way all over the world.

So I gave up on UNESCO at the time and I went to Sweden and took charge of a laboratory for the biggest manufacturer of hardboard mills in the world. Once again–as with some of my former jobs–I liked the environmental aspects of this position. I was working with a company that helped make it possible to take waste fibers and miscellaneous trees that had no real commercial value … and turn them into useful building materials.

There were some difficult problems involved in this work, of course. I had to analyze the technical problems as a chemist, as an engineer, and as a production man. In the end we found some very simple solutions to the questions we faced, and we increased both the capacity of the mills and the quality of the boards they manufactured by 25%. This was, I think, a rather major development … and we did it mostly by showing our engineers how to be better housekeepers. We put in some scrubbers and we showed the people who ran the mills how to keep the wires clean that the hardboard pressed up against during one step of its manufacture. It was that simple.

And I’m sure that, just as soon as you had that one licked, you went out looking for new worlds to conquer.

Well, at the time, Truman began advocating his Point Four Program and–since I’d been proposing something like that at both the U.S. Embassy and the State Department for some time–I thought I had to be a part of it.

So I came back to the States and offered my services and–because of my interdisciplinary background–was hired by the Housing and Home Finance Agency which, after about a year and a half, sent me to India as International Building Materials Advisor.

Now in India I was soon embarrassed because they wanted me to build a house. And I’d never done that before. Here I was the Official Building Materials Man … and I’d never built a house.

So I sat down and studied the situation and realized that the main limitation I faced was the sheer poverty of the people for whom I’d be designing my dwelling. These people had virtually no money at all, and only the very simplest of tools to work with. So I designed a mud-walled, thatched-roof and bamboo house of one room plus kitchen. It had a simple little cowshed, alongside and the stove was just a ten-quart bucket propped up on a couple of bricks. It wasn’t much, but it cost just $80 … which was within the means of the market I was designing the house for.

And then, in four stages, we upgraded that very simple dwelling until it was a very, very respectable home which still cost only $500. We got some nice publicity with that house in India and in the British journals and everyone declared it a success … even though I thought it was rather unsuccessful.


I wasn’t physically comfortable in the place. To save bricks, you see, I had kept the building’s walls fairly low and then I had topped it with an asbestos roof. When I walked around inside, with that hot roof right over my head, I could feel a lot of heat radiating down on me. I thought the house was a failure.

In the long run, however, that was the building’s greatest success. Because it got me to thinking about how I could build a really comfortable dwelling there in India with nothing but a very few readily available materials. Without electricity, without air conditioning, without all the crutches that designers and architects back here in the States take for granted.

How could I use just what I had at hand–mud, cow dung, the sun, the simplest of tools, maybe a very few pieces of sheet metal or insulation–to construct a comfortable house? How could I heat the building with nothing when it was cold and cool it with nothing when it was hot?


Well I realized–as primitive man must have realized and as the animals realize but as modern man very seldom realizes–that the answer was actually quite simple. I’d just have to design with the climate. And what kind of climate did I have to work with in India’? One in which the days were generally too hot for comfort, but in which the nights could become quite cool.

Now the value of nocturnal radiation–the cooling effect we get at night, especially when the sky is clear–is often overlooked by modern man … although it’s been known by our species for thousands of years. Out in the desert, for instance, the effect of night sky radiation is actually strong enough to freeze water when the temperature of the air around that water is still as high as 50° F. They’ve been freezing ice in the deserts of Iran this way for centuries.

I hadn’t thought about that.

Very few of us do these days. But I had to think about it, you see, because nocturnal radiation was one of the very few things I had to work with. That, and the hot sun during the day. And, as I began to consider these two forces, I realized that it was only a matter of balancing one against the other to get the round-the-clock comfort I wanted to build into my house.

And this was in ….

This was 1954. Others had been studying nocturnal radiation but I think I was one of the first to actually use the phenomenon this way … as the other side of the solar radiation coin, so to speak. Once I had carefully analyzed the situation, though, it was a very obvious thing to do.

I’ve found, you see–whenever faced with a complex problem–that, almost always, the first and wisest step to take in solving that problem is to reduce it–confine it–to its simplest terms. In this case–when I was trying to design comfort into an extremely low-cost house for use in India–my most basic goals were to [1] protect the building’s living area from outside heat during the day and [2] open it up so that it could radiate heat away during the night.

Viewed in those extremely simple terms, it became very obvious that, no matter how I placed the insulation in the dwelling, that insulation would be correctly positioned only about half the time. If I set it up to keep heat out during the day, it also kept cool air out at night … and if I left it off entirely so that the cool of the night could come into the house, the day’s heat would also flood in. What I needed to be able to do was move the insulation from one place to another and back again during every 24-hour period.

And that’s how your principle of movable insulation was born.

That’s right. I called it my “dry-therm” principle because I was moving dry panels of insulation back and forth to control the heat–the thermal quality–of a given living space.

For example. A person lying on a bed under a metal or an asbestos roof can be very comfortable if he has just a simple movable panel of insulation between himself and that roof. If the radiation from his body goes up and hits the insulation and is reflected back down to his body … he’ll be warm. If the radiation goes up and the insulation isn’t there, his body heat will travel on to the roof where it will be absorbed and re-radiated off to the night sky … and he’ll be cool.

It was just a question, then, of using that piece of movable insulation very much as you’d use a blanket. You could change the positions of the panels with your fingertips. It was a very simple arrangement … too simple, in fact.

Why do you say that?

Because, as I quickly learned, the people in under-developed countries don’t want to use a simple idea if they feel you’ve developed it just for them. That hurts their pride and their sensitivity about living in an underdeveloped nation. They can only afford the very simplest of technology, of course, and they know that so they want it … but only after it’s been accepted and used in the United States, or Britain, or France.

So, over the next 15 years or so–while I kept trying to get through to the Agency for International Development and to the United Nations, and while I worked on research projects in Venezuela and Colombia for private firms–I continued to develop my ideas into something that would be acceptable by American standards of comfort.

During the course of this work, we actually evolved six different thermal conditioning systems … all based on this principle of movable insulation.

Such as?

Well the first was the “solar collection” principle . . . the idea of moving insulation back and forth, in our experiments over two containers of water so that one container is exposed at night and covered during the day while just the reverse is title for the other. This, of course keeps the water in the first bucket cold and that in the second warm … 24 hours a day.

Then there’s the principle of mass or thermal lag … the flywheel effect. You can demonstrate this by simply covering a container of water with insulation and leaving it there day and night. The temperature of the mass of water will hardly change at all during a 24-hour cycle if the insulation is thick enough. The pyramids–with their tremendously thick walls surrounding very small burial chambers–are probably the best examples of structures which use this principle of thermal lag to maintain a constant temperature in their work areas At certain times of the year, however, this very simple phenomenon of thermal lag can be used to make even ordinary house more comfortable than almost any combination of furnaces and air conditioners or other “conventional” methods of comfort control.

There are also ways to increase the amount of the heat that a building’s roof can radiate into the sky after you’ve pulled a panel of insulation back to expose that roof. You can, for example, simply flood the surface with water. This, of course, works even during the day. We tried it once on a house in Arizona and, even when the outside temperature was 95° F, the temperature inside the building was so low that I had to wear a sweater and coat to stay comfortable.

Well. That led me to think about putting the sweater around the water up on the roof, instead of on myself. So we pill a plastic bag around the water to stop its evaporative cooling And we found that when we covered the bag of water during the day with a panel of insulation that the mass of the liquid would absorb heat from the living space that it covered. Then, when we slid our insulation back at night the container of water would radiate that heat off into the night sky. This kept the house comfortable up to a daytime outside temperature of about 106°.

Beyond that, for temperatures ranging up to 110 or 115 degrees you could flood some extra water right over the bags of the fluid. This you see, was another variation yet on our basic idea.

And what about temperatures even greater that 115°?

Then, for the first time, you had to Use a little electricity to run a small fan-coil This stirred the air slightly in the living space, picked up some of the heat it contained, and dumped that heat on the roof And that’s all you needed to maintain American standards of comfort in the Arizona house.

Would that system work anywhere?

We’re talking now about my Sky-Therm system. When I added water to the “dry-therm” theory and began developing variations on the basic idea, the whole concept evolved into what I’ve now patented as the Sky-Therm method of heating and cooling a structure.

Yes, one variation or another of my system should work almost anywhere. A Sky-Therm incorporated into a house on, say, the Gulf Coast–where it’s hot and humid in the summer–might differ markedly in both installation and operation, from one designed for a dwelling in New Mexico. And each one would probably differ considerably from the Sky-Therm system used to heat and cool a building in upper New York State. But one or another of my designs should work quite satisfactorily from the equator all the way up to the Arctic Circle.

They’re designed to do that, you see. My system purposely has a great deal of flexibility built into it so that, while a Sky-Therm house on the equator hardly resemble one constructed on the Arctic Circle each would have been carefully calculated to work with the climate in which it’s located.

Before we begin the design of a Sky-Therm house we always ask. “What materials and what energy forces do we have to work with on this particular site? ” And then we try to use those materials and those forces so efficiently that the house will keep its occupants comfortable at all times with no additional input of energy at all.

Now this is not the way that conventional homes are designed today. Our builders and architects have gotten into the habit of saying, “Well, let’s put up a Cape Cod here and a ranch style over there and we’ll use big window walls in both buildings.” And then they just pump, pump in as much oil and electricity and natural gas as they need to heat those buildings in the winter and cool them during the summer. Instead of letting the climate help them design their structures they just build whatever happens to be in fashion at the time. And then they make the houses tolerably comfortable inside by consuming massive amounts of energy. They overpower the climate, instead of working with it.

But that can’t continue much longer.

No, a day of reckoning is coming. We’re running out of the fossil fuels that make today’s wasteful way of life possible. Sooner or later, all the architects and builders are going to have to take the Sky-Therm approach to designing a house … whether they know it yet or not. And, of course , once we begin to got back to a closer understanding of nature and man’s relationship to the sun, we’re automatically going to question a great many other ideas that are accepted today as part of the conventional wisdom. And we’re going to start developing whole new concepts of who and what we are … and why … and what our rightful place in the universe really is.

From the way you say that, I’ve got a feeling you’ve already begun developing those new concepts on your own. Would you care to share any of them with us?

Well I’m still working on them. But my work with the Sky-Therm concept–with allowing the natural climate of an area tell me how to design a house–has led me into drawing certain conclusions.

I’ve come to believe, for instance, that our rate of technological advance now exceeds our rate of evolution. We’ve learned how to manipulate our physical surroundings to make ourselves comfortable almost anywhere on the earth’s surface … when, basically, there are certain parts of the world that we simply shouldn’t be living in.

We’re a Mediterranean–not an omniclimatic–animal. We belong in the earth’s temperate zones … but our technology has made it possible for us to heat the planet’s arctic regions and cool its tropics enough to make ourselves comfortable there. That, in one sense, is what the energy crisis is all about. We’ve learned to use enough energy to make ourselves comfortable in areas that we’re not really physically adapted to live in.

But, spread out as we are, we’re already beginning to find our sheer numbers to be a problem. How can we pull back from all the marginal areas of the world that we now live in? We’d soon be stepping on each other!

Exactly. We’ve already overpopulated the planet. Any time some of us have to move into a climate that isn’t really suited to our species, we’re overpopulated. We need population control right now if we expect to stop our destruction of the earth.

If we all lived in the areas that we’re suited for–with enough space around each of us to supply our shelter, food, energy, and other needs right at the point of use–we wouldn’t be tearing the planet apart in our search for fossil fuels and other resources. We wouldn’t be polluting our landscape and water and air. We wouldn’t be seriously considering utterly ridiculous “solutions”–such as nuclear energy and space stations and the colonization of other planets.

There’s only one real solution to the problems that man has brought to the world. We must severely restrict our population and we must each learn to live on the energy which falls on our own roofs.

Solar energy.

Yes, but–even there–we’ve got to learn to work with nature. We can both use and misuse even solar energy, you know. I delivered a paper on this subject–Solar Energy, Solar Power, and Pollutionat the 1972 International Solar Energy Society meeting in Paris. And in that paper I pointed out that the direct use of solar fall on a house is completely non-polluting … while the collection of that same solar fall in one area, its conversion to electricity, and then its transportation to another area can be very polluting.

There are schemes being bandied about, you know, for hanging solar collecting satellites in the sky and then beaming the energy they gather down to earth. And there are other plans to collect solar energy in 100mile-square areas of the desert and turn it into electricity and transmit it into our big cities.

But who needs any more junk orbiting the earth’? Our space scientists are already complaining about the amount of man-made garbage we’ve shot into space. And who needs to cover the desert with solar cells? That’s just another way of polluting the landscape. And who needs to build more transmission lines from the desert into the cities’? Transmission lines are eyesores. And who needs to manufacture all the hardware we’ll need for these projects? We’re going to have to burn a lot of fossil fuels just to run the factories and machines we’ll have to use to set these new systems up … and t hat means more pollution right there. And what will that electricity run when we get it into town’? Air conditioners. Furnaces, A lot of equipment that will also have to be manufactured, and advertised, and sold, and hauled from factories to stores to apartments and houses … and eventually junked. And that means even more pollution … not to mention the thermal changes that will take place in the atmosphere when you collect heat in one area, change it to electricity, and ship it to another part of the country. But if you just take the solar energy that falls on your roof and use it right there to warm and cool your house … ah, that’s a different story! We can do that without creating any real pollution at all.

Mr. Hay, has your work with solar energy led you into formulating any other theories or concepts?

Oh sure One that I’ve come up with which you might find interesting is my idea about cool black and warm white.

Cool black and warm white?

Yes. It’s become almost holy writ, you know, that black always absorbs the sun’s rays and warms up, while white always reflects solar energy and stays cool. We paint the collectors of our solar energy systems black and our barn and factory roofs white for this very reason.

Why then are polar bears white and why do so many tropical animals have a black or a dark tint to their coats? Why are so many Nordic people from far northern Europe light skinned with almost white hair … while Negroes from equatorial Africa are very, very dark with black hair? If black always absorbs heat it would seem to make more sense for polar bears to be black and for Negroes to live in the arctic zones of the world. They’d stay warmer that way. And if white always reflects heat, tropical animals should be light–not dark–and blonds should hail from the equator. They’d have evolved to stay cooler that way.

But that’s not the way nature designed them … and nature doesn’t seem to make the kind of mistake that our conventional theory of black and white tells us it’s made. How do we explain this contradiction?

Well I explain it by saying that black does not always absorb the sun’s rays and white does not always reflect it in just the way we’ve been taught to believe. There’s also what I call “cool black” and “warm white”.

I can best explain cool black by telling you to lay a piece of black metal out in the noon summer sun alongside a thick black coat. And then, an hour later, I want you to go back out and pick them both up. What will happen? Well, of course, you’ll burn your hand on the metal … but the coat will still be cool enough to handle.

Why? Because-even though the surface of the coat is just as hot as the surface of the metal-the fibers immediately below the coat’s surface act as insulation instead of a heat sink. So, as fast as the surface of the coat warms up, it radiates its heat right back into the atmosphere.

And that’s why tropical animals are darker. That’s why people from very hot countries have thick black hair. The sun’s rays never get a chance to reflect down through the hair to the skin underneath. Instead, they’re absorbed right at the tips of the hair and the resulting heat is quickly carried away by radiation and convection. The outer surface of the body of hair becomes an automatic heat dumping system that is insulated from the skin underneath by the mass of hair in between.

And just the opposite holds true, I suppose, for the polar bear?

Yes. I think that the polar bear is white–at least in part–so that what sunlight falls on its body will reflect down through the animal’s coat and finally convert itself into heat well down in under the insulating hair. This allows the bear to stay warm during some seasons while converting less of the food it eats directly into heat energy. It can then store more of that food in the form of fat for use as body heat during the winter. In short, the polar bear’s white coat allows it to survive on less food than if that coat were some other color.

That theory makes sense as far as hair and the coats of animals go. But what about skin pigment. Why are Negroes black and Nordics so light complexioned?

Because we’re all just as we should be. Because our ancestors adapted supremely well to the conditions they faced for generation after generation.

The Negro is black because his ancestors would have developed skin cancer if their bodies hadn’t learned to turn the enormous quantities of the sun’s rays they received into heat energy right at the skin’s surface. The excess heat was then dissipated by evaporative cooling. The Nordic, on the other hand, grew up–generation after generation–with far less exposure to the sun. He needed to convert much more of the small amounts of ultraviolet light he received into vitamin D if he was to stay healthy. So his skin became very thin and contained hardly any pigment. His skin became a very efficient converter of ultraviolet into vitamin D.

It’s just a matter of adaptation then.

Just natural adaptation to the sun. And once you realize that, you begin to forget the arbitrary distinctions of race that we carry around in our heads and our hearts and you start to have a greater appreciation for the brotherhood of all mankind.

Well there are some other ramifications, of course … about who should live where and that sort of thing.

Of course! Very light-complexioned people suffer more skin cancer when they move to the tropics. When Negroes first went to Chicago in large numbers during the 30’s, a tremendous number of them–something, I believe, on the order of 90% of those who moved–developed rickets. They simply hadn’t adapted yet to the small amounts of ultraviolet light they received up there.

Now, this is no reflection on one or the other. But I’m very light. Nature has designed me to live in a more northerly climate. Dark skinned people are designed to live closer to the equator. We might be a wiser species if we’d make at least an effort to do what nature has evolved us to do.

Does your theory about cool black and warm white have any application beyond those you’ve just mentioned involving animals and people?

Yes. An especially good example can be seen on Lanzarote, the northernmost of the Canary Islands. Volcanoes there around 1730 covered large parts of the highland inches deep with black cinders. Yet, despite the fact that the land receives only six inches of rain a year, it grows watermelons, tomatoes, grapes, potatoes, and other crops. Why? There isn’t an agriculturalist in the United States that knows how to do that.

My theory about cool black provides, I think, most of the answer. The sunlight failing on the black surface of the cinders is immediately turned to heat which is radiated right back into the atmosphere. And the thick layer of cinders between that surface and the ground underneath acts as insulation which keeps the earth cool. This allows the soil to retain and make maximum use of the little rainfall it receives.

In addition to that, the trade winds constantly blow moist air across the island and a little of that moisture condenses on those cinders every night when they get cold under the nocturnal sky. And that condensed moisture trickles down through the cinders and recharges the soil below every morning.

That sounds plausible.

Yes. Well we could use this idea ourselves in some farming regions … but, when I discussed it with the U.S. Department of Agriculture, the people I talked to were extremely skeptical at first. They’d been trained, you see, to avoid black at all times and they couldn’t believe that black could do what I said it would do.

Then I found that the idea got a completely different reception when I talked to some agricultural people in Greece. “But of course!” they said. “You’ve just explained what happens when we burn Thessaly.”

And I said, “Well, I don’t know anything about burning Thessaly.” So they told me.

It seems that for 2,000 years the peasants in the Thessaly region of Greece have been burning off their fields every year. And for the last few decades, the agriculturalists have been trying to get them to stop.

First the agriculturalists said that the burning would kill the bacteria in the soil. But that was disproved. Then they said it was wrong because it destroyed nitrogen that the soil needed. But someone proved that it actually took more nitrogen to compost the unburned straw in the soil than the straw contained in the first place. So then the agriculturalists said that the straw shouldn’t be burned because it was needed to open up and loosen and aerate the soil. But 20 years of tests proved that wrong also. And then they said that the straw was necessary to prevent erosion. But tests showed that it was really the stubble-which was left after the burning anyway that stopped the erosion.

So the agriculturalists lost.

Oh, I suppose they’re still coming up with new reasons for the peasants not to burn that straw. It’s interesting, though, that those guys with all the ideas haven’t asked themselves whether or not burning the straw does any good. And I think it does. For both a cool black and a hot black reason.

See, what happens when those peasants burn that straw is–first–there’s a layer of insulating black ash left on top of the soil.

A cool black.

Right. A cool black. The sun’s rays hit the surface of that ash and are immediately changed to heat energy which rapidly dissipates into the atmosphere. And the fluffy layer of ash between that top surface and the soil underneath keeps the heat from reaching the earth. As a result, the soil stays cool and retains its moisture … which is an important advantage in that relatively dry climate.

But then, in the late fall and winter when the seasonal rains fall, that fluffy black ash is broken down into nothing but a black pigment. It loses its insulating value. And once it’s just a black coating stuck directly to the earth’s surface, it becomes a hot black. It helps the soil absorb the sun’s rays and stay warm. This allows the next year’s crops to come up earlier and grow much faster. So maybe those peasants know what they’re doing after all.

Well, as you said a little while ago . . . there’s no arguing with something that works. On the other hand, the agriculturalists you just mentioned and an awful lot of other self-proclaimed “experts” seem to have wiggled their way into positions of power. And even though they don’t know what they’re talking about most of the time, they seem to have the funds and the authority to ram their pet theories down the throats of all us poor peasants.

Yes, I know. This is a special peeve of mine. Perhaps because I left school before I received my Ph.D. which, in the minds of some of the bureaucrats I’ve dealt with since then, somehow seems to taint any idea I might work with.

But this whole business of Ph.D.’s and other fancy titles and bureaucratic credentials of all kinds is vastly overrated. The whole field of research has become institutionalized. It’s become a chummy club of back-scratchers who publicize each other and recommend each other for government and foundation grants and name each other to special commissions.

This is one, of the big problems in the field of solar energy. Certain people have come to dominate “the club”. They’ve gotten themselves associated with the U.S. Government or the U.N. or a big university and now they have big public relations organizations working to see that they get all the publicity and the funds, and they decide which forms of solar energy will be developed and which will be ignored. And, of course, since Big Government and Big Business and Big Organizations finance them, the projects that generally get worked on the satellites in the sky and the 100-square-mile collectors with the transmission lines running off to a city somewhere–are the projects that will mainly benefit those groups.

The really valuable solar energy ideas–the non-polluting ideas that would allow you and me to become energy independent by harnessing the sun’s rays which fall right in our own backyards and on our own roofs–never seem to get much attention. The “experts” and their public relations machines never seem to publicize those ideas.

They never seem to publicize the kind of ideas you work on.

Oh it’s not just me. There are others. People such as Steve Baer and Harry Thomason. People who’ve taken their own time and their own money and worked with their own hands to develop a solar energy system that works. I think that individuals like this–I call them “creative activists”–should have half the votes on the board of directors for any foundation or government agency that controls funds for solar research. The people who actually come up with the ideas and get their hands dirty out in the shop should have at least half the say-so when it comes time to parcel out the money.

Good idea. That would probably keep the people engaged in solar energy research–or any field of research, for that matter–working a lot more efficiently than they now work. But what about those individuals themselves? How would you have them prepare themselves for a career in research?

I’ve become very blunt with my recommendations on that subject because, it seems to me, far too many of today’s young people think they can do research work without properly preparing themselves for it. I get exasperated when I see individuals leave the field of sociology or art or whatever to make methane gas . . . especially when they want to make it in an old inner tube.

Now there’s nothing wrong with making methane gas and there’s nothing wrong with making it in a tube. But it’s ridiculous for someone with a background in sociology to fool himself into thinking that he’s doing meaningful research when he does something like that. He might be solving his own energy problem and I think that’s a very fine thing to do. . . but he’s making a mistake if he kids himself into believing he’s advancing the state of methane gas production in any way that’s going to save millions of barrels of oil a day. That individual should be working in the field for which he was trained.

However, if he searches his soul and finds that methane gas research is what he really wants to do, then that person should change his fields. He should go back to school and take chemistry courses and biology courses and engineering courses and learn the basics of the field and prepare himself to research methane gas. But there isn’t any shortcut. He’s going to have to learn the fundamentals before he can expect to advance the state of the art in his newly chosen field.

I have much the same advice for anyone who wants to protest something. You see these young radicals in the United States and India and South America and all over the world. And they’ve always got their fists up in the air and they shout and their elbows go up and down and up and down.

Well, if they’d attach a pump to those elbows, maybe they’d get a little useful work out of the demonstrations. Otherwise, why bother?

I didn’t like the political situation in St. Louis when I was a young man. But I didn’t demonstrate about. it … I changed it. I went to work as an individual and I changed it. So why be a copycat? Why just shake your fist in the air because a bunch of other people are shaking their fists in the air? If you don’t like the way things are, go to work and constructively change them.

Be an individual. Forget what’s fashionable and what others are doing. Find out what you want to do, then prepare yourself … and do it.