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Tags: HomeworkOne

Product Concept: Insulation keeps hot and cold separate. Is it feasible to create a system that would allow radiant heat in during the winter, not just keeping the heat in, but allowing additional heat in as well. Windows do this already, but have high conduction losses relative to a well insulated wall. Is summertime cooling possible? (This may violate the second law.) Conceptually, they would be similar to "breathable materials" that are able to selectively allow moisture to pass in one direction but not the other.

I started my search for radical design with They make prefabricated and custom homes from discarded cargo containers. These homes are cheap, rugged, and take from the waste stream rather than consume raw materials. This fits my definition of a radical design.

This led me to

"Dumpster divers and bargain hunters rejoice! Technology has come to save you time (and grime). A very recent gift of the Google Map Mashup comes in the form of GarbageScout, an interactive online mapping system that allows you to alert community members to great groundscores in your neighborhood.

Better than Craigslist, and even Freecycle, this system is not restricted by specific locations or multi-step posting processes. You can even post your finds online while prowling the streets, by taking a phone photo and sending a pix message to with a short description." -

The site combines Google earth with RSS feeds to allow dumpster divers to share the location of good finds, instantly. We generate large amounts of waste unnecessarily because there is little infrastructure to connect the ones with junk to the ones seeing treasure.

The search forked to solar cell roof tiles:

"Everyone knows that using solar energy is a great way to conserve energy AND lower your energy bills. So why haven't more people jumped on the solar energy bandwagon yet? Researchers think it has a lot to do with aesthetics and lack of convenience (not to mention cost). Photovoltaic solar panels, which were invented in 1954, consist of grids of raised black cells that, up until now have usually come in the form of large clunky rectangular panels that either stand alone, or must be bolted onto a roof. In addition to being aesthetically unappealing, some homeowners have been reluctant to embrace the technology because installing solar panels may require puncturing an existing roof and bolting on metal supports, which can void the roof's warranty. Fortunately, electronics companies have seen the light, and realized the market potential for aesthetically appealing solar panels that can be integrated into the roof of one's house. Finally, there are now quite a few aesthetically appealing brands of BIPV, (or Building Integrated Photovoltaics) out in the marketplace today.

Sunslates, made by Atlantic Energy Systems are photovoltaic cells which can be mounted to traditional slate roofing tiles and can be networked alongside each other in horizontal strings of 24. Due to their roots as regular roofing tile, installation is relatively straight forward and can be accomplished by any trained roofer & electrician. Furthermore, Sunslates work well in both new building developments and re-roofing applications, as they require minimal "roof penetration" for running wires to the inverter.

Bigger companies like General Electric, PowerLight, and Sharp have all jumped on the BIPV bandwagon as well. Sharp is currently the biggest manufacturer in the world of integrated solar roofing panels. Compared to Sunslates, Sharp's new solar roofing modules are bigger, longer, and instead of snapping onto regular roofing tile, they replace roof tile. Sharp's BIPV lay flat on the rooftop, interlocking smoothly with standard roof tiles. They are compatible with most shapes and sizes of roof tiles used in new residential construction, with one module replacing five standard concrete tiles.

So now that you know how easy and stylish it can now be to revamp your house for solar power, what are you waiting for?" -

This jogged my memory about solid state air conditioners. they are very inefficient, but are getting better.

"How the Thermoelectric Works . . .

Thermoelectrics are based on the Peltier Effect, discovered in 1834, by which DC current applied across two dissimilar materials causes a temperature differential. The Peltier Effect is one of the three thermoelectric effects, the other two are known as the Seebeck Effect and Thomson Effect. Whereas the last two effects act on a single conductor, the Peltier Effect is a typical junction phenomenon. The three effects are connected to each other by a simple relationship.

The typical thermoelectric module is manufactured using two thin ceramic wafers with a series of P and N doped bismuth-telluride semiconductor material sandwiched between them. The ceramic material on both sides of the thermoelectric adds rigidity and the necessary electrical insulation. The N type material has an excess of electrons, while the P type material has a deficit of electrons. One P and one N make up a couple, as shown in Figure 1. The thermoelectric couples are electrically in series and thermally in parallel. A thermoelectric module can contain one to several hundred couples.

As the electrons move from the P type material to the N type material through an electrical connector, the electrons jump to a higher energy state absorbing thermal energy (cold side). Continuing through the lattice of material, the electrons flow from the N type material to the P type material through an electrical connector, dropping to a lower energy state and releasing energy as heat to the heat sink (hot side).

Thermoelectrics can be used to heat and to cool, depending on the direction of the current. In an application requiring both heating and cooling, the design should focus on the cooling mode. Using a thermoelectric in the heating mode is very efficient because all the internal heating (Joulian heat) and the load from the cold side is pumped to the hot side. This reduces the power needed to achieve the desired heating." -

This seems like a technology begging for a radical use.

Like the "Chill Can"

"It took Tempra Technology two years since we first wrote about them to find a company to use their self-cooling cans, a little startling considering the average American drinks about 22 gallons of beer annually, but Miller has finally signed on to launch their beers in Tempra's I.C. Cans in mid-2007.

The cans are regular 16 ounce size but only contain 10.5 ounces of liquid, as the rest of the space contains the cooling apparatus: a dessicant that when activated draws the heat from the beverage into a heat sink, causing the drink to lower a minimum of 30F in a remarkable three minutes. We can't imagine the I.C. Can beers will go for the same price as beers in regular ones, but they should sell well nonetheless, even at a premium—we've yet to meet anyone who enjoys lugging coolers around, especially not on hot summer days. Between this and the Guinness Surger, it's a good time to be a beer drinking nerd." -

But that problem has been solved already, and more efficiently. The effect is reversible, however.

"The 3 TE effects are named for Seebeck, Peltier, and Thomson. The easiest way (I believe) to think about thermoelectricity is to realize that electrical and thermal currents are coupled. The particles that carry electric charge in a material also carry heat. The three TE effects are just three ways in which this coupling is realized, and all are closely related. In fact, knowing the Seebeck coefficient as a function of temperature allows one to calculate the Peltier and Thomson coefficients." -

Refridgeration of vaccines and other medications is a serious hurdle to attempts to fight disease in third world nations. That requires electricity. Could thermoelectrics be used as generators between the sun/shade? What are the current ...searching leads to a villiage in Columbia:

" Gaviotas is a village of about 200 people in Colombia, South America. For three decades, Gaviotans - peasants, scientists, artists, and former street kids - have struggled to build an oasis of imagination and sustainability in the remote, barren savannas of eastern Colombia, an area ravaged by political terror. They have planted millions of trees, thus regenerating an indigenous rainforest. They farm organically and use wind and solar power. Every family enjoys free housing, community meals, and schooling. There are no weapons, no police, no jail. There is no mayor.

The United Nations named the village a model of sustainable development. Gabriel Garcia Marquez has called Paolo Lugari the "inventor of the world." " -

The entire community is itself a radical design, and fosters the invention of smaller radical designs.

Fork back to buildings, and finally a product: Looking back at the flow, the one conection I can see is the need for insulation.

"Resists Heat Flow To maintain comfort in your home, the heat lost in winter must be replaced by your heating system and the heat gained in summer must be removed by your air conditioner. Insulating ceilings, walls, and floors decreases this heat flow by providing an effective resistance to the flow of heat.

Heat flows naturally from a warmer to a cooler space. In winter, heat flow moves directly from heated living spaces to adjacent unheated attics, garages, and basements, or to the outdoors; or indirectly through interior ceilings, walls, and floors – wherever there is a difference in temperature. During the cooling season, heat flows from outdoors to the house interior.

Controls Sound Adding insulation beneath drywall in a typical wall configuration can increase the sound transmission coefficient STC rating. In most homes, walls between rooms are only marginally effective at blocking noise. Made of drywall and lumber alone, these interior or partition walls have poor Sound Transmission Class STC ratings. An STC rating is a number used to characterize the acoustic performance of a wall, floor or ceiling—the higher the STC rating, the less sound will be transmitted between rooms. By far the easiest and most economical method for controlling noise is to install insulation in the wall cavity. Click here for more info about sound control and insulation.

Controls Moisture A vapor-resistant membrane (commonly called a vapor retarder) attached to batt or roll insulation decreases the possibility of moisture vapor condensing to water within the structure.

Even though you need some moisture in the air you breathe, too much moisture in your home can cause problems. When moist air comes in contact with a cold surface, some of the moisture may leave the air and become liquid, or condense. If moisture condenses inside a wall, or in your attic, you will not be able to see the water, but it can cause a number of problems." -

For a more detailed break down of insulation types and uses, look at:

New Direction: Insulation keeps hot and cold separate. Is it feasible to create a system that would allow radiant heat in during the winter, not just keeping the heat in, but allowing additional heat in as well. Windows do this already, but have high conduction losses relative to a well insulated wall. Is summertime cooling possible? (This may violate the second law.) Conceptually, they would be similar to "breathable materials" that are able to selectively allow moisture to pass in one direction but not the other.

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Page last modified on September 12, 2006, at 11:12 PM