2 posts tagged “waste as food”

Link: Not a Watt to Be Wasted 

The March 17/2008 TIME Magazine explored scavenging 'free energy', from sources such as:

• the leg brace invented by Max Donelan and Arthur Kuo
• vibration of bridges, dance floors and even the human heart
• energy from raindrops or motion of fabrics
• waste heat from power plants, internal combustion engines and other sources. 

With the exception of scavenging heat, most of these techniques deliver only small amounts of energy, from microwatts up to five watts for the leg brace, enough energy to power a high-efficiency LED cluster that produces roughly as much light as a 40W halogen bulb.  In comparison, model aircraft engines weighing 9 ounces (250 grams) can deliver more than 800 watts of power at maximum speed. 

Scavenging thermal energy can deliver more power, but only from high quality waste heat.  The amount of work that can be done depends on the temperature difference between the heat source and the surrounding environment.  The high temperature exhaust of internal combustion engines is a good example and can be tapped using processes such as the BMW turbosteamer concept or converted directly to electricity using the thermoelectric effect.  On the other hand, thermocouples are still relatively expensive - another approach may be to redesign the underlying processes to be more efficient and generate less waste heat. 

Note: this is a public post

According to Treehugger, Nokia is working on a prototype cellphone that can disassemble itself in 2 seconds, compared to 2 minutes using traditional methods.  A heat source activates 'shape metal alloy actuators' which basically cause the phone to disintegrate into component parts.  WorldChanging has a more detailed description of the process. 

In Cradle to Cradle, William McDonough emphasizes the importance of designing products and services for both the biological and technical resource cycles.  By  ensuring that the two cycles are kept separate, it is possible to keep pollutants out of the environment.  More importantly, it allows creation of closed-loop technical cycles that eliminate the concept of waste through re-manufacturing.  The current recycling methods typically downgrade the quality of the material such that they often are only suitable for lower-grade products.  Eventually, the value of the recycled material is such that it is discarded. 

The work of Nokia and other companies who are developing Active Disassembly opens opportunities to design products and systems that allow extraction, testing and re-use of working components in new phones.  Through good design, components that cannot be re-used or repaired can be further broken down such that they become the raw materials for new components, closing the loop.

Aside from dramatically reducing the both waste and resource consumption, the concept lends itself to 'product as service', where you no longer buy a cellphone but rather the services provided by that cellphone.  If the product no longer works or new features are required, the physical phone could be exchanged for another one.