Solar Power isn't Feasible!

Solar Power isn't Feasible!
This cartoon was on the cover of the book "SolarGas" by David Hoye. It echoes the Sharp Solar slogan "Last time I checked nobody owned the sun!"

Saturday, February 23, 2008

An Open Letter to the security guard Karam Ahmad Alladin about using a refrigerator to heat water...

Photo: Karam (left) with T.H. (Taha) Culhane and fellow security guard at the Al Azhar Park gate.

Dear Karam,

Many people know you only as the friendly Egyptian security guard who protects foreign visitors to the Aga Khan Trust for Culture and guards the gate at the ancient wall separating the well-to-do dining in fine restaurants in the verdant playground Al-Azhar Park and the crowded urban poor ekeing out a living in the muddy winding unpaved streets of Darb Al Ahmar. Others know you as the reliable plumber always willing to lend a hand (as you did when I was building a solar hot water system on the roof of our Solar Cities building in your neighborhood).

I have the great fortune to know you as all this and more; I know you as Karam the visionary and innoventor, a man who is always thinking and dreaming of new possibilities. I know you as Karam the public welfare enthusiast, who has taken me around the community to meet with 80 year old pensioners in 700 hundred year old buildings with sunny roofs who would like their grandchildren to live in a more hopeful Egypt and are thus willing to let us (and to help us!) experiment with home-made hot water systems in their building. I know you as Karam, as generous as the meaning of the name "Karam", a storehouse of local information, the karam who gave of his time and risked his job one night to take me by the hand to a decrepit, recently closed, once beautiful, but still fascinating 300 year old public bath to meet with the owners so we could find a way to revive this lost tradition in historic Cairo. I know you as Karam the solar enthusiast who explained to the owners how they could bring back the public baths by switching to solar heating and lighting and thus, in the long term, keep costs low so that the whole community could enjoy the health and psychological benefits of abundant hot water.

Photo: Karam (left) introduces Taha (wearing his characteristic Solar Powered Back Pack) to the Wahiya family that has been running the recently closed 300 year old Darb Al Ahmar Hammam (Public Bath), around the corner from the Solar Cities office, for more than 80 years. Karam used to go there as a child, and wanted to see if there is a possibility to re-open it and run it on solar energy. The baths used to be fueled by waste heat generated from the cooking of "Ful" (Fava beans); the heat was supplied by the burning of waste paper from the city's garbage, collected by the Wahiyas (the garbage recyclers who came from the Oases, or "Wahiya" in the desert, preceeding the migration of the Zabaleen from the Countryside 50 years ago. Both the Wahiya and the Zabaleen are intensely interested in reviving the public bath tradition and finding sustainable ways to heat the water. The burning of waste material to heat water was forbidden for health reasons, but the costs of oil, gas and electricity make heating public baths too expensive to keep operational costs within reason.)

Photo: Solar Cities Coordinator Mahmoud Dardir (left ) on a roof overlooking the public baths with the owner of the local garment factory housed within the building. Karam (right) has convinced the factory owner to let Solar Cities build a demonstration solar hot water system on his building so the family running the public baths can get an idea of how the system works. The factory owner loved going to the public bath next door as a kid, saying it was easy for his mother to get all the kids clean in no time. Many residents, who must now heat water on the stove to get a bucketful of hot water for their evening "shower", lament the passing of this tradition -- there used to be more than 300 public baths in the Darb Al Ahmar region -- so many that at the turn of the century a visitor remarked "you could bathe in a different bath every day of the year!" Today there are only two remaining.

I also know you as Karam the security guard with a real interest in the true security of the Egyptian people -- security from the things that really count -- security from hunger, security from power failures, from water shortages, from impending energy crises and from the rising price of goods.

Finding solutions to these problems, you have always understood, is "real homeland security". And you have impressed on me that America's homeland security depends on real homeland security in Egypt and the rest of the Middle East, where freedom from the tyranny of worry is the only thing that can really prevent young idealists from getting hijacked into following the empty, deadly promises of fundamentalist insanity.

Today at the "Umwelt" show in a shopping mall in Dortmund, northern Westphalia (the part of Germany where the eternal optimist, Candide, came from in Voltaire's social satire) my wife and I were reminded of you when we saw a vendor's exhibit on the Geothermal heat pumps he had for sale.

The vendor was a very forward-thinking German "Braucherwasserwarmepumpe" company called "Vaillant Deutscheland GmbH & Co." Brauchwasserwarmepumpe is an extremely long word that literally translates into "Needwaterwarmingpump". I had the good fortune to meet Vaillant's patient and knowlegable salesman, Timo Krugman, who knows that you don't have to hard sell renewable energy products - moving customers to clean, sustainable energy systems and away from its addiction to filthy carcinogen-spewing, smelly, war-fostering fossil fuels is like moving water from the mountain to the sea. It is so inevitable (though so long in coming) that it sells itself. All the salesman has to do is build your confidence that his company is the most reliable and knowlegeable. In this spirit, Timo was not at all pushy, on the contrary his interest was in helping me understand the physical principles, the engineering, the mechanics and the environmental and economic advantages undergirding the ground source heat pump revolution, something virtually unknown in Egypt, but well established in Europe and California.

In order to capture the attention of the public, wandering between McDonald's and GameStop and H & M, the principles behind how ground source heat pumps work (and why it is worth investing 20 to 30 thousand Euro in such a heating and cooling system) the clever folks at Vaillant had taken a compressor out of a refrigerator and mounted it on a display board that showed a picture of a house and had some pipes simulating a geothermal system.

It turns out that a heat pump is basically just a super-sized refrigerator or air conditioning system that makes use of the stable temperatures underground as a heat sink.

In true science museum fashion, the clever vendor had hooked up a normal refrigerator compressor up to some copper heat exchanger coils above and below the compressor, with digital temperature read-outs next to both. The upper coils were mounted on the drawing of the household's basement water storage tankand the lower coils were mounted on the plastic pipes running down the picture of the household's backyard, from the backyard lawn to the sandstone 100 meters deep.

The legends around the pictures explained that a geothermal heat pump (a full sized version of which was sitting next to the exhibit) is basically a refrigerator or air conditioner compressor that uses the heat generator by compressing the HFC refrigerant to heat water in the house, and lets the cold created by the endothermic phase change of the refrigerant (after it passes through the expansion valve -- the larger piece of copper tube with the tiny coil beneath it that you find on the back of your fridge) be reheated by the warmer ambient temperature of the water in the geothermal tubes. This warmed gas can them be compressed back into a hot fluid as the cycle starts again back at the compressor.

The vendor had a button you could push that would start the compressor. Within minutes the compressor had reached 56.6 degrees C, and you could put your hand on the copper coils to fell for yourself what the temperature gauge showed.

Meanwhile, the lower coils began to accumulate frost, just like the inside of your freezer, which kids could touch and play with as they observed the temperature gauge dropping to - 2.2 degrees C.

It was a simple way to demonstrate the principles of geothermal or ground source heat pumps. But to us it was much more -- it was proof of "Karam's concept."

Do you remember, early on, before I got to know you and thought you were "just another security guard", when you were letting me into the gate at the old Ayyubid wall one night around 2 a.m. after I had taken my wife to Salah Salem street to catch a cab to the airport, when you asked if I thought is was possible to use your refrigerator to get hot water?

As we climbed up the inside of the ancient stone staircase by the light of your torch you suddenly paused and said something like "You are Taha who builds solar hot water systems in the community. I would like very much to build a solar hot water system on the roof of our house, but even if I could afford the materials, I don't think my uncle would agree to it. We are having a dispute and since he technically owns the roof space he might forbid me.

"But I have been thinking for some time now why it wouldn't be possible to use the heat behind the refrigerator to make my water hot. I noticed that the compressor gets very hot, and we waste this heat letting it go into the air through that metal grill behind the fridge. All it does is make the kitchen hotter -- the one place in the house we don't need extra heat! So I was thinking, 'couldn't I use that heat to make hot water?' It would not only provide hot water, but it might keep the kitchen cooler. Also, if the hot water tank was above the fridge we would naturally have some water pressure, we wouldn't have to buy or build a stand, and we wouldn't have to mount a heater on the wall, which is a problem in these old buildings with crumbling walls. What do you think?"

I remember replying that I thought the idea was brilliant, and that I certainly thought it was possible, and that I had even discussed the idea once with fellow Solar Cities founder Mustafa Hussein, the local carpenter, when we learned his roof couldn't hold the weight of a solar hot water tank (I had read somewhere on the web once that an American company during World War II had built and marketed hybrid refrigerator/water heaters, but that they had ceased production when oil became cheap in the 1950's.) But we abandoned the project, I said, because sadly I had no experience in such matters and gaining experience takes time and money. I told Karam back then we would simply have to try if we could ever get some seed money to do some experiments, but I didn't know when that would be because, as I told him, it is hard to get seed money for unproven ideas. And it is certainly hard for the poor, like us, to put money into things that have an uncertain payoff.

Photo: Carpenter and Solar Cities local co-founder Mustafa Hussein, on his way home from the woodshop, discusses his new device with Karam -- an easier method for putting grooves in aluminum sheets so that copper pipes can be put inside -- a very important step in making absorber plates for home-built solar hot water systems.

Sadly, in all that time, we never did get money to make hybrid refrigerator/water heater experiments, though we fortunately DID get the money from U.S. AID to build the solar hot water heater that we are going to put on your new apartment now that you have moved from your uncle's!

But I never forgot that question you posed when I first met you, and today Sybille and I found the answer in a shopping mall in Dortmund! Because it was a hands-on-exhibit, and not some theoretical paper or some 2 dimensional diagram, I got a real firm sense of how we can build your refrigerator/heater, and I am hoping somebody can help me translate this letter into Arabic and share it and these pictures with you.

First of all, I would suggest you remove the compressor from the bottom at the back of the fridge and place it on the top of the fridge where it will be closer to your fridge top mounted water tank. That way we won't lose more heat to the air (which is why those refrigerator coils are there on the back of the fridge to begin with) and we won't have to invest much money in insulation; we want the shortest run from the compressor to the hot water tank as possible. The heat exchanger could come right off the compressor, and to increase its heat we could even wrap some of the copper coils around the compressor itself. This should also keep the compressor cooler and that should make it run more efficiently, no? I think I would make a metal stand for the water tank, and place the compressor underneath it on the top of the fridge, and put styrofoam around the whole thing so that all the heat goes into the water, but I'm not sure about that part -- I think we need a way for the compressor to cool down when the water is hot in the storage tank, so maybe we should leave it open. Experimentation will tell.

The bottom part of the system, where the expansion valve is, would remain the same, cooling the freezer from the top (because cold air falls; it thus seems better to cool the top part of the fridge).

I have posted these pictures and suggestions on the internet, Karam, because real engineers with much better understanding will be able to comment and help improve the system, making it more and more feasible to bring it to fruitition. Hopefully, next time I am in Cairo, we can start experimenting.

Until then, keep coming up with those great ideas, keep up your innovative curiosity, and keep having the insight and courage and enthusiasm to bring them up to visitors to your beleagured community who have the great great fortune and luxury to be able to travel around the world meeting with people and seeing exhibits that can provide solutions and turn the dreams of "the other 90%" into realities.

I know that such a combination of local and outside expertise can bring true homeland security to all of us!


Taha Rassam (T.H.) Culhane
Founder, Solar CITIES


Andy said...

I've come up with a way of getting funding for renewable energy and energy efficiency. It's a model that may also work for funding the work you do in Egypt (which should be receiving much of the billions going to Iraq. . .). Anyway, I'm sure you are familiar with peer to peer lending. Sites such as allow lenders to provide micro-credit loans to borrowers in third-world countries. The borrowers pay back the loans at no interest, and once the loan is fully paid back, the lender can withdraw her money or invest in another entrepreneur. one thing you might try is becoming one of kiva's field partners, so that people can actually give laons to families that you work with. another option is the business i'm trying to start here in providence. the idea is to create a peer-to-peer lending site where the loans go to energy efficiency, solar pv and solar thermal installations in providence. the loans wold be paid off with the energy savings from the installation. the name of our non-profit will be (i registered the domian, but haven't mde the site) we are submitting a plan to the rhode island business plan compettiton, and if we win we get 50k to start the non-profit. Our goal is to double the amount of solar installations in the state of RI (currently 92 pv installations), create jobs and save lower income families money (they get a $2,000 federal tax credit. . .) We also want to use the site to get low interest loans so that people can install LED light bulbs on porches and things, or buy efficient appliances.

What do you think? I can't wait to talk to you and tell you about my thesis--i'm working on a project that is truly revolutionary!



Marcel said...

Excellent stuff gentlemen.

I consider it a privilege to even be able to read this letter and gain insight into your relationship and the inventive fruits that it is bearing.

I shall be thinking about this hybrid heater/chiller some more I think. (and not sleeping I fear!)

God's richest blessings to you both.

in Christ