Wednesday, September 3, 2014

What's right with cities? Lecture 1, Urban Ecology, Mercy College

For the next 2500 words I'd like to talk about cities. Cities – where only about 30% of humanity lived when I was born and where today more than 60% of our species live. And counting.
As the population swells from today's 7 billion up to the 9 billion we expect when most of you who are in college today are my age, we already see a planet in which there are more people living in cities today than existed on the planet when I was in high school. Think about that for a second and contemplate this graph:
(Population curve)

That's us for most of human history, this is us in 1900, this is us when my parents were in high school, when I was in high school, when most of you were in high school.
Now we have a situation – if cities are conceived of as problems, 60% or more of us living in them is a BIG problem. (For developed countries the figure is actually up over 80%).

Cities are where almost all resources are consumed and almost all wastes are produced. You could boldly argue that as many, if not more problems are created by our pesticide laden factory farms, ploughed and harvested by smoke belching fossil fueled tractors, filled to the brim with methane belching manure generating cows and chickens and pigs crammed together in CAFO's – Concentrated Animal Feeding Operations
(Picture of CAFO)

But this would be a false way of conceiving of today's farms which are not so much part of the countryside as an appendage of the city, created to serve the cities' rising populations
(picture of Mcdonald's over 6 billion served sign)

and therefore to be accounted for as an essential part of what we call the urban ecological footprint.
(Picture of footprint)

Your ecological footprint is the amount of land and resources and impact each person has, the amount of land you are basically stomping on in order to get what you think you need to survive. Arguably people living in cities have a radically larger ecological footprint than people living in the real countryside who actually live off the land – transportation alone – of food, raw materials, inputs – accounts for 28% of energy consumption.

And let us speak for a moment about inputs to factory farming and how the city robs the countryside through farming.

Back at the turn of the last century, Karl Marx and Friedrich Engel's predicted the “degeneration of agriculture” because all of the nutrients from the fragile soil of the English countryside were being shipped in food products to the city where they were then consumed and either thrown into garbage pits or flushed down toilets, making their way down the Thames to their final burial place in the ocean. ( Marx and Engels reasoned that if the nutrients were not brought back to the farms and replaced, the soils would eventually give out.
This grim prognostication has indeed come to pass all over the world, with the American “dust bowl” tragedy illustrating the danger. The antidote has usually been the very expensive process of using fossil fuels to manufacture fertilizers which are then transported from industrial center to farm at more expense to try and grow more food. With topsoil eroding the result is a diminishment in the nutrtional quality of our food and a much lower carrying capacity for the land. (Picture of dust bowl).

Whether we are talking about the mining of the soil, the mining of mineral reserves, or the mining of forests, the consequence of city living is to drawn down the capital reserves of our farms and fields in an unsustainable way.

 As the economist E.F. Schumacher pointed out in “Small is Beautiful” in the 1960s, nature is like a giant banking account and our income is the amount of sunlight we receive and its immediate transformation into food and heat and wind and moving water.

 Our fossil fuel reserves and our soil and forests and coral reefs and mountains and ore deposits are our savings accounts.
The city, with its dense population and eco-system blind construction, can not live off of the income its land-mass and surface area consume so it uses up our savings faster than they can be replenished.
Hence cities, as we know them, are inherently unsustainable.

But need this always be so?

Can we imagine a city that generates enough income to be sustain itself?

One of the fun ways I like to answer that question is to turn negatives into positives. 

Many so-called “environmentalists” are angry at human beings, and perhaps rightly so. They will tell you that people are stupid and selfish and greedy and can not be convinced to do the right thing.

 My response to that is to accept people as they are and see how we can make best use of our less endearing traits.
So let's be crude for a moment and consider that people are... well.... a$$-holes. Literally. And let's consider that the more people there are in a location, like the city, the more a$$-holes there are. Literally. The city is full of a$$-holes.

Is this necessarily a bad thing?

To answer this question we have to answer the question, “what does an a$$-hole do?”.
Essentially an a$$-hole gives us Sh!t. More a$$-holes means lots and lots of sh!t.
And what doesn't come out of the...let's be more polite and say “anus”, city dweller's tend to throw into the garbage. 

Between 40 and  60% of the food coming from the farm doesn't even make it into people's mouths, much less all the way down the tube we call our body to the anus. Most of that energy goes into smelly garbage bags and eventually makes its way to landfill or into the ocean. Just as Marx and Engels' described.

Major tragedy. 

An even worse tragedy that urbanization wrought was the horrible diseases those organic wastes visited upon human-kind before they ended up in the ocean. On the way from our houses and apartments and restaurants to the dump or the river the fecal material too often contaminates drinking water leading to deaths and illnesses from cholera, typhoid and other water borne diseases. Meanwhile the organic wastes from plant and animal material that didn't pass through our bodies attracted rats and flies and feral cats and dogs and racoons and pigeons and innumerable other mammalian, avian, insect and other consumers who became vermin and vectors of disease. The fleas on the rats that came into our cities in search of the left-overs we threw away caused the bubonic plague that killed tens of millions in Europe in the middle ages and continues to wreak havoc in poor communities today.

And yet, all of this could have been avoided. If we had simply designed our cities to turn all that accumulated material into energy and fertility to grow more food and create more products there would have been nothing for the so called “bad guys” to eat and grow on. All kitchen and toilet wastes could have been turned immediately into energy and safe fertilizer without ever leaving the community or neighborhood much less the city, and without endangering anybody. But for some strange reason very few people talk about this, preferring to try and throw or flush problems away and causing misery downstream for somebody else.

Imagine going back in time and having the power and influence to convince rulers, policy makers, engineers, architects and city planners, and most importantly, the men and women who live and work in cities, that kitchen wastes and toilet wastes are only problems because they are being wasted. That they are only problems because they are being used in the wrong way – thrown out and flushed away instead of put back into service.

Imagine if you could go back in time and convince others that there should never have been any wastes at all – that the city is actually a huge accumulator of energy and fertility, not just a way-station on the path toward increased entropy where everything we consume turns into some form of difficult to manage and hazardous pollution.

I'm here to tell you, at the start of our class, that civilization's greatest triumphs and greatest tragedies revolve around kitchens and bathrooms – something most of you have and take for granted, and something that so many many others around the world have never had the privilege of having.

We all need water, food and shelter, in that order of importance, and we all need some place to safely deposit the results of our consumption of food and water.

The problem is that most people in the world still dump their organic wastes, those coming from the parts of the food they didn't eat and those coming from the parts that passed through their bodies, into streams and rivers and lakes and oceans, or into ditches. A huge number simply dump them in the street or into somebody else's back yard.

Pathogens and vermin get into the water supply and into homes and kill and sicken people – my good friend Hanna Fathy, from Egypt, for example, tells the story of how his baby niece was killed in her crib, bitten and infected by rats that were attracted by the food waste in the garbage but found it easier to eat the baby's ears and nose than try to tear through the sealed plastic garbage bin.
They had done everything they could to keep rats from the food waste they could not eat, but the attempt at hygiene backfired in a city where the rats and roaches and other creatures trying to compete for a living on a planet with less and less living space find the city to be the best place to try and survive.

Thee tragedies could be avoided by proper attention to what organisms are after through the lens of urban ecology. All of us -  humans and non humans alike -- flock to and  live in cities because there are tremendous advantages to accumulation – we call some of these effects “agglomeration economies” and others “untradeable interdependencies”.
Agglomeration economies are the utilities or benefits that come from coming together or “agglomerating”. The more people there are in an area, the more wealth, the more ideas, the more accumulated resources and of course the more so-called “wastes”.

Untradeable interdependencies are the values we gain that we don't have to directly pay money for (they are thus called by economists “untradeable” as they have no financial market, not because we don't actually trade them in some way) and they come from our being together “interdependently”, as a result of sharing space. The learning and information sharing and deal making that goes on in the cafeteria, outside of class, in the elevator, by the water cooler, riding the subway – all of these are the untradeable interdependencies that make coming to school and paying high tuition worth more than sitting at home doing an online class – if you take advantage of them.

 They explain why people will suffer the daily commute into the city or some other densely populated area to go to school and work and shop even when many of the actual goods we need can be obtained more cheaply and with less stress outside the population centers and urban cores. They explain why the Zabaleen garbage pickers of Cairo moved with all of their animals from the countryside to build an informal slum on the outskirts of the city only to live in piles of garbage – they knew that they despite the poverty and the filth and indignity they could make a better living in or near the city where resources have pooled and agglomerated and people are densely packed, than out in the fields and farms and villages.

Other, non-human animals feel the same way.
And so everybody, everything moves to the city. It is where the action is.
But of course this creates huge problems.
The question again is, “DOES IT NEED TO?”

I have a certain answer to that question from my years of working with and living among the so-called “poor” in general and the Zabaleen trash recycling community of Egypt in particular.

 My answer is “the city can solve all of its own problems if the people in the city recognize the city as the solution space that it really is and stop looking at it as merely a consumption space. The city needs to be seen as what the futurist Alvin Toffler called a “Prosumer” environment.

A Prosumer environment is one where people (and other creatures) produce as well as consume, so that each citizen acts as both producer and consumer, hence “prosumer”. The operating ethos of the prosumer environment is what we now call “industrial ecology”. In Industrial Ecology we model our cities after Natural Ecologies found in the larger environment we call “Nature”. In Ecological Systems the output from one process becomes the input for another and everything that can be recycled is recycled in as close to a closed loop system as is possible.
The Zabaleen trash recyclers taught me that there was no such thing as garbage. They come to the city to find metals and plastics and wood and paper and minerals and carbon and other organic materials and transform them, through their labor and intelligence, back into industrial inputs that can be put back into service.

The Zabaleen men gather and sort trash and clean and sell most of the inorganic materials to factories around the world. They also run their own small factories. They also keep pigs in the city, in their apartment buildings and on their rooftops,  along with goats and sheep and cows and rabbits and ducks and chickens, and these creatures help to turn the organic wastes into nutritious meat and useful leather and bonemeal.
What the Zabaleen didn't know how to do, or couldn't afford to do,  given their poverty, was  safely contain all the organic wastes so they would not be available to undesirable organisms or how to create energy and fertilizer from all of this activity.  Thus the toilet wastes of their animals and their own bathrooms, and the parts of the food waste that even their animals wouldn't eat, created problems, caused odor and diseases and infestations of rodents and insects.

But I maintain to you that this isn't as difficult a problem as it seems once you look at it the right way.
The mere presence of rodents and insects and disease causing microbes is a powerful indicator that there is a lot of gold still there in them there hills! If the so-called wastes weren't valuable, the other non-human beings – the one's we don't necessarily want living around us, wouldn't be there, would they? They are only there because we are giving them things to eat. They are only there because we are supplying them with resources.

Once you have an urban ecology perspective you begin to see things differently. You begin to see signs of possibility and hopeful solutions everywhere. Imagine vermin and disease being mere indicators of riches to be found! The trick then is to design processes and systems to capture those hidden values that all these non-human creatures can see. And how do they see the world? In terms of ENERGY.  All living things, including humans, are in pursuit of energy, most of it from the sun. Food is solar energy stored in a kind of transportable battery – the chemical bonds that make up plant and animal tissues, carboyhdrates, proteins and fats. Oil is also solar energy stored in the chemical bonds of petroleum – long dead animals and plants.

And so it turns out that the worst problems caused by cities are really there because we are actually throwing away organic batteries that are still filled with energy. Even the smoke smog and pollution from our trucks and buses and cars and factories are merely indicators that we haven't used up all the energy in those chemical bonds. And all we have to do to turn cities from problem causers to problem solvers is capture that energy and put it to work.

 In this class we will explore how this is done.

Tuesday, November 5, 2013

Hydrogen -- is it hype or is it hot?

The other day in class I started describing how easy it is to make hydrogen.  According to  in 

How the Hydrogen Economy Works

 "The problems with the fossil fuel economy are so great, and the environmental advantages of the hydrogen economy so significant, that the push toward the hydrogen economy is very strong."

To make this happen though, we all need to learn what hydrogen is and how it is made, and we've looked at the fact that you can make hydrogen using simple drain cleaner and waste aluminum foil. (see 

Run Your Car on Hydrogen from Aluminum Soda Cans and Lye

). In this article he even shows how to run a car on home made hydrogen.

Monday, December 3, 2012

Robin Hood and the Joule Thief, Raiding the Rubbish to Help the Poor

(The above video "Hangout with an inventor for #deSTEMber" is the live feed of the National Geographic/Google Science Fair Google + Hangout where NG Emerging Explorer T.H. Culhane shows how to build the Joule Thief and run a superbright LED off of aluminum can tabs and zinc drywall screws, creating the "Solar CITIES Tab Torch" that he used in Nepal on an expedition. The video also shows how to make a homopolar motor and a lemon battery)

On a dark frigid spring night in a frozen mountain pass in the Himalayas, my pup tent covered in snow, 5000 meters above sea level, I lay in my sleeping bag reading a comic book. My source of light?  5 super bright white LED bulbs lit by a chemical reaction between a soda can tab, some wood ash from the Sherpa fire, and a stainless steel scouring pad.

We were on a National Geographic/Blackstone Ranch/Mountain Institute sponsored Expedition to a remote village in the Hinku Valley not far from Mt. Everest, but well off the beaten path, 6 days trek across the steep icy mountain range from Lukla.

Our goal was to share ideas for renewable energy generation with the villagers and help build capacity in the region to help them live sustainably in their homeland even as their  forest resources dwindle and the climate changes.

We found that there was already widespread use of solar electric panels thanks to a government sponsored program and the work of many NGOs over the years, but for many families the cost of the panels was still a barrier.

Perhaps worse, the cost and weight of batteries, and the hassle of getting them up the narrow and dangerous mountain passes,  made storage of the electricity produced by the  few hours of sunlight they received a daunting  prospect. And because they need the few small  photovoltaic panels they had to keep their own batteries from deep discharge and ruin, they charge the few trekkers who come through on the way to Mera Peak  between 3 and 5 dollars an hour to charge their batteries.  As a consequence most trekkers brought many non-rechargeable batteries with them for flashlights and cameras, which, once spent, one can find lying scattered along the trail.

The trekkers also are fond of canned sodas and beer, and warm spaghetti,  and because of the extreme costs of transporting anything in the region, the aluminum  cans and aluminum dinner plate foil  only go one way -- up.  They get consumed in the lodges and dumped in garbage pits by the river, never to return to Katmandu for recycling.

Looking at the trails in the Khumbu and Hinku Valleys over the past two years through the eyes of the Zabaleen trash recyclers, I began to ask if there was a way to make use of all the discarded batteries and aluminum foil and can waste throughout the region.

After experimenting a bit I found that indeed there is a lot we can do with that 'garbage' because it contains a lot of embedded chemical energy.  The key to getting that energy out and making it useful turns out to be the humble "JOULE THIEF CIRCUIT".

A Joule Thief is a very simple thing to build.  All you need is:

  • A Blue or White LED (Other colors are fine, too)
  • 2N3904 Transistor or equivalent
  • 1k Resistor (Brown-Black-Red)
  • Toroid Bead
  • Thin wire, two colors (magnet wire works, .6mm)
  • Alligator clips and/or a breadboard
Here is a simple diagram of how to build it from

Picture 1
And here is their photograph of theirs:

Picture 2

When I did my first build I used the instructions and schematic from the "Evil Mad Scientists" at

I find their schematic very helpful:

Picture 3

The have a lot of great instructional photographs to show you how to build a Joule Thief step by step, so I highly recommend you click on their link above.  They show how to wind the torus with wire.  My recommendation is that you cut a piece of double stranded wire about the length of your arm and thread it through the bead and then start wrapping until you have 10 - 12 coils.  Twist two of the wires from opposite sides and opposite colors together and that gives you your wire to connect to the positive terminal of the battery of to the stainless steel pad (in the case of an aluminum can tab battery).

The contribution I've made recently to a siimple Joule Thief build is to show people how to do it without soldering, simply using alligator clips.  Here is my quick sketch and some photographs of my results:

Picture 4

Picture 5

I use seven different alligator clip wires and use colors to help make it easy to figure out what to connect where.   When using a battery I use small circular neodymium magnets for quick connecting of my wires to the battery terminals:

Picture 6

Picture 7
No soldering or clipping necessary as the magnets hold the alligator clips on to the battery terminals just fine.

Picture 8
The picture above shows one of the red alligator clip wires coming from the wound together leads of the torus to the positive terminal of the battery. The negative terminal of the battery, with the black alligator clip wire, goes to the negative lead of the LED bulb.

Below is a closeup of the LED bulb wiring:

Picture 9

The black wire coming from the negative terminal of the battery  is on the negative lead of the LED and so is a green wire which then goes to the collector on the transistor. On the positive lead of the LED is a red wire going to the Emitter on the transistor, and a yellow wire going to the red wire coming off of the torus bead (opposite the twisted pair).

Here is a close-up of the transistor; note that I refer to it with the flat side facing me and from left to right the leads are Emitter, Base, Collector. Note the white alligator clip wire going to the center of the Transistor, which is the "Base" and acts like a "switch" or a "valve", regulating the current going through the collector and emittor. Think of it as a faucet.

Picture 10

The following image shows that the white alligator wire is connected to the free white wire coming off of the toroid bead. You note that the red free wire coming off the bead goes to the yellow wire which we connected to the positive lead of the LED.  You also see that the twisted pair of opposite side red and white wires on the torus bead go to the red allligator clip wire that goes to the positive terminal of the battery.

Picture 11

In the photograph below we see that the white wire coming off of the torus' white wire is connected to a 1 KiloOhm resistor which is then connected to another white wire which goes to the base (center pin) of the transistor.

Picture 12

Picture 13
Picture 14

Picture 15
Picture 16

As you can see from the image below, the completed circuit is really easy to build, and enables one to light an superbright 3V LED from a single 1.5 Volt battery;

The fact that the Joule thief allows one to run a 3V LED from a 1.5 or 1.2 Volt battery would itself be astounding, because it means you only need half the number of batteries to get the same light.  That in itself is a tremendous savings (imagine only needing to carry half the number of batteries up to Mt. Everest in your backpack to get the same light!).

But it gets better!

Some of you are thinking "wait, maybe it enables you to use a single 1.5 volt battery to light a 3V LED instead of the usual two, but doesn't it just make that battery last half as long?

Great question, but the answer is that the Joule Thief, which works by building up and collapsing a magnetic field around the torus (which acts as an electromagnetic inductor) actually is more efficient than using a battery directly because it PULSES the energy to the LED.  You see the lightbulb shining brightly, but in fact it is turning on and off very rapidly as the magnetic field of the inductor builds up and discharges again and again. That means that though the light appears to be on all the time it is actually turning on and off and saving energy because it isn't on all the time.

But it gets even better:  It turns out that the Joule Thief enables the battery to keep supplying electrons to the light long after the battery is normally considered DEAD.  So the battery actually lasts much much longer than a normal battery.  And for this reason, in Nepal I was able to pick up dead batteries that tourists had thrown along the trail when they no longer ran their cameras, and use them to run my flashlight!

I've observed "dead" batteries working down to about 0.5 Volts.  Normally a 1.5 V battery is considered dead when it reaches 1.0 volts.  But the Joule Thief can "steal" the remaining energy much below that.

And that got me thinking -- could I use other sources of between 0.5 and 1.0 Volts to run a 3V LED?

I was experimenting with aluminum garbage  and a solution of lye made from wood ash from the Sherpa's fire (Potassium Hydroxide, used to make soap in the old days)  to create hydrogen (a chemical reaction I knew  about and used to show my students dating from when I taught Chemistry at Marlborough High School in 1989!).  Hooking a voltmeter up to the reactants to see what was going on I observed a voltage during the reaction of between 0.5 V and 0.9 volt.  So I lowered my concentration of lye to keep the hydrogen bubbling to a minimum and hooked everything up to a Joule Thief.

The reaction was astonishing -- I was able to light the LED to full brightness, just from one coke can tab and a piece of stainless steel.  I had, in fact, created an aluminum oxide battery. And I found that I could light not just one LED from this simple procedure, but 5, all super bright!

This meant that no matter I went in the world, as long as I had some aluminum can tabs in my pocket and could gather some hardwood or fruitwood ash from a fire and had my joule thief, I could run a flashlight indefinitely, never needing to worry about batteries again!  Each aluminum can tab lasted me up to 6 or 8 hours before needing to be replaced.

Here are some pictures of the reaction, using drain cleaner fluid (sodium hydroxide) as the source of lye:

 Note that when I press the aluminum tab down on a paper towel that has a few drops of lye on it and get it to touch the stainless steel scouring pad it produces 0.56 volts as it lights the 3V LED (a stainless steel  spoon, fork or knife,  will work instead of the scouring pad  as well, but more surface area gives more light!)

When you take the light out of the circuit you can sometimes get up to 1.2 Volts from the chemical reaction between the lye and the aluminum can tab.

I call this invention the "Solar CITIES Tab Torch" because it is a flashlight (Torch) that runs on Aluminum Can Tabs.  It will work on aluminum foil and aluminum yoghurt covers too, or aluminum dinner plates. But if you don't have aluminum, don't worry, it also works with Zinc -- so you can carry around a pocket full of drywall nails too, or plumbing pipe, or a bit of your zinc roof:

So the Joule Thief, coupled with my discovery in Nepal of the voltages I could produce from scrap aluminum or zinc and wood ash-based lye, now enables anybody in the world to light their world from garbage.

And that is why, as I sat in my tent all those frigid nights in the most remote areas of the Himalayas, I was never worried that I would run out of light, no matter how dark the days and nights, come rain or shine, so long as I had a source of garbage and ashes -- things we never seem to run out of no matter where we are in the world.  And that is why I could spend my time and energy reading comic books, rather than worrying about where the next civilized outpost was where I could buy batteries.

Electricity is all around us, and through the eyes of the Zabaleen, you can see it everywhere, if only we can, as the song goes, "look beyond the garbage in the streets to see the garbage in our minds", mental garbage that prevents us from seeing that everything we need is often already right in front of us!