Self-Cooling Soda Bottles?

Researchers work to shrink technology that harnesses sun's energy to
both heat and cool

July 11, 2006

Every day, the sun bathes the planet in energy--free of charge--yet few
systems can take advantage of that source for both heating and cooling.
Now, researchers are making progress on a thin-film technology that
adheres both solar cells and heat pumps onto surfaces, ultimately
turning walls, windows, and maybe even soda bottles into climate control
systems.

On July 12, 2006, Rensselaer Polytechnic Institute (RPI) researcher
Steven Van Dessel and his colleagues will announce their most recent
progress--including a computer model to help them simulate the climate
within their test structure atop the RPI Student Union--at the Solar
2006 Conference in Denver, Colo.

For 4 years, the researchers have been working on their prototype Active
Building Envelope (ABE) system. Comprised of solar panels, solid-state,
thermoelectric heat pumps and a storage device to provide energy on
rainy days (literally), the ABE system accomplishes the jobs of both
cooling and heating, yet operates silently with no moving parts. NSF is
supporting the team to determine if a microscale version of the
technology will function effectively.

According to Van Dessel, thin-film advances could potentially lead to
functional thermal coatings composed of transparent ABE systems. Such
systems might vastly improve the efficiency of temperature-control systems.

"The ease of application would make it possible to seamlessly attach the
system to various building surfaces," he added, "possibly rendering
conventional air conditioning and heating equipment obsolete."

Van Dessel hopes a thin-film version of the ABE system will see uses in
a range of industries, from aerospace--in advanced thermal control
systems in future space missions--to the automotive industry, where it
could be applied to windshields and sun roofs, giving them the ability
to heat or cool a car's interior.

"It also may be possible to one day use the ABE system to create
packaging materials for thermal control," he added, "which could lead to
things like self-cooling soda bottles."

Additional information is available in the RPI press release linked below.

-NSF-

Van Dessel will be giving a technical presentation on Wed., July 12th
during the "Energy Efficiency, Renewable, and Green Technologies"
session of the Solar 2006 conference, from 2:00-3:30 p.m. Van Dessel
will discuss how the ABE system works, and the computational model he's
developed to test the system's efficiency.

Abstract:

ISEC2006-99127; Technical

Development of a Computational Model for a Prototype Testing Room With
Integrated ABE System

Authors: Steven Van Dessel and Xu Xu; Rensselaer Polytechnic Institute

Active Building Envelope (ABE) systems are a new technology for space
heating and cooling, which integrate photovoltaic (PV) and
thermoelectric (TE) technologies. In the ABE systems, a PV system is
used to transfer solar energy directly into the electrical energy; this
electrical energy is subsequently used to power a TE system. Depending
on the direction of electrical current applied to the TE system, ABE
systems can operate in a heating or cooling mode, and can compensate for
thermal losses or gains that occur through a building's envelop or other
thermal enclosure. ABE systems make use of solar energy, a clean and
renewable energy resource. In order to assess the feasibility of the ABE
system, we have developed a prototype ABE-window system. In conjunction
with developing this prototype, we have also developed an outdoor
testing room to test our ABE window system. Our current experimental
setup allows us to measure the temperatures inside and outside of this
window testing room.

To assess the effectiveness of the ABE system while in operation in the
testing room, it is necessary to determine the comparative temperature
for the same testing room without the TE system operating, for similar
environmental conditions. There are two main methods to establish such
control. The first method is to develop two identical experiments and
test them simultaneously, one with, and one without, the ABE system in
operating mode. The second method involves computing the indoor
temperature through a simulation method. In our research we have opted
for this second method.

In this study, we have built a computational model to predict the indoor
temperature of an outdoor testing room and its integrated ABE system.
The computational model uses the finite differential method, and
includes the computation of solar radiation, heat transfer through the
testing room surfaces and the ABE-window, and a model for the indoor
air. We have verified the model's accuracy by comparing the simulation
results of this model with actual temperature data. We have found that
there was good correlation between the model's prediction for indoor
temperature, and the actual temperature measurements for our testing
room. The model will be used in further studies to assess the
effectiveness of the ABE system.

Session: 5-1 Component Simulation-1

Media Contacts
Joshua A. Chamot, NSF (703) 292-7730 [email protected]
Amber Cleveland, Rensselaer Polytechnic Institute (518) 276-2146
[email protected]

Program Contacts
Perumalsamy Balaguru, NSF (703) 292-7016 [email protected]

Principal Investigators
Steven Van Dessel, Rensselaer Polytechnic Institute (518) 276-2011
[email protected]

Related Websites
Steven Van Dessel homepage: http://www.rpi.edu/~vandes2/abe.htm
Related RPI press release:
http://news.rpi.edu/update.do?artcenterkey=1246&setappvar=page(1)

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