A surprising amount of what the first world considers garbage or waste actually contains energy or other properties that could be harvested: not just plastic and other landfill debris, but manure, too. Using manure as fertilizer (after lots of processing of course) isn't a new idea in history, although I believe turning it into energy is.
Just a quick comment, Ann. Though the use of human waste for energy doesn't appear to be common, my friends who have travelled extensively inform me that the use of dried animal dung as a cooking fuel is alive and well in the third world. Nothing like a high-fiber diet to create a high energy output.
Scott, I was thinking of less direct, more complicated modern energy harvesting methods. But you're totally right. The dung of animals that eat a diet full of grass and other fibrous plants has been burnt as fuel all over the world for thousands of years. You don't even have to be a farmer: Plains Indians burnt buffalo dung for that purpose.
Too bad that Bill couldn't have invested a couple of shekels into his company to make WINDOWS the SEAMLESS operating system that it COULD HAVE BEEN, INSTEAD of the SERIOUSLY FLAWED program that it is, especially considering that it will be celebrating its 30th anniversary in the near future!!!!
Designs that work within different realities, cultures, and resources ties into the "Societal Engineering" curriculum at Boston University, which was covered in a recent DN article. My son is a ME student there and I'm very impressed with their program. A recent group of students took a diagnostic unit they designed to Africa and discovered there are places where AA batteries are not available. Very invaluable experience for new engineers.
Not to sound harsh or cynical, but better sanitation leads to a larger population, further straining the carrying capacity of the land and increasing the vulnerability to disruptions in water, weather, harvests, etc. A friend who has done charity work in Africa has seen many "point solutions" actually make matters worse because a holisitic view was lacking.
@kenish: You're definitely right about the importance of a holistic view. However, I think the concern about overpopulation is misplaced. Belgium and the Netherlands have higher population densities than El Salvador, yet no one ever says that Belgium or the Netherlands are overpopulated. And many of the poorest African nations have lower population densities than the U.S. Preventing the deaths of 1.5 million children per year would be a good thing.
@Dave and Rob- All good comments! I wasn't speaking to population density, but rather "carrying capacity"...the ability of the land and infrastructure to support a population density. For example we have a very high population density here in So Cal, made possible by modern infrastructure. Remove the water supply, agriculture, distribution, and utilities and then see how many can subsist in our desert after 2-3 years. Most of Sub-Sahara Africa is beyond carrying capacity as evidenced by the famines, epidemics, and wars that plauge the area.
Saving 1.5 million lives is, of course, a fantasitic goal....but my previously mentioned friend has seen situations where the saved infants die from worse causes later in childhood or general suffering and poverty increase because the population becomes even more unsustainable. I hope the families, villages, and countries have a plan to feed and educate 1.5 million more people.
Again, this sounds incredibly harsh but my friend has really opened up my eyes to many well-meaning but ill-fated attempts at "aid" from developed countries. Of course there have been success stories too, such as the Rwanda coffee bike project and the Nestle boycott.
Basically a protected compost pile for excriment layered with straw or sawdustfor a year, then closed for a year to make sure no pathogens get out, or 2 years if you're squeemish, then used on the garden or whatever. Didn't need a grant or special materials or Bill Gates for this. Of course no one really makes any money off it either so it doesn't get much attention. jerry
The biggest problem with toilets is the use of water which is getting scarce, with costly infrastructure (piping), and disposal of the wastewater/ excrement. I heard of the toilet using vacuum to flush (similar to those in airplanes). The vacuum can be generated with a hand-powered pump.
- No water is used
- The waste is not diluted: the volume of waste is much reduced
- the toilet can be installed anywhere without the need for extra infrastructure
The challenge is to decompose the waste through an anaeorobic process (without oxygen). Alternatively an evacuation service can transfer the waste to a central location where the waste is processed. If possible methane from the excrement can be used for generating electricity.
A new service lets engineers and orthopedic surgeons design and 3D print highly accurate, patient-specific, orthopedic medical implants made of metal -- without owning a 3D printer. Using free, downloadable software, users can import ASCII and binary .STL files, design the implant, and send an encrypted design file to a third-party manufacturer.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This discussion will examine what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.