Nano-Engineering Making Big Strides
Scientific and technological advances are increasingly powered by our ability to build things at the atomic level. Mimicking processes that take place in biology, scientists are using custom self-assembling structures to power new molecular breakthroughs. At the atomic level, there is no fundamental difference between the various scientific disciplines. Improving nanotechnology is converging them at an accelerating rate.
An often-overlooked transformational technology is air conditioning. We don’t usually think too much about it unless it stops working. It has, however, had profound impacts on how we live and could add profit to your portfolio…
The great majority of residential units use vapor compression refrigeration. These systems work by compressing a refrigerant fluid in a pump, which raises the temperature of the refrigerant. After being compressed, the high-pressure vapor is run through a tube to a heat exchanger. Here, the heat is radiated outside.
Once cooled, the refrigerant condenses from a vapor into a liquid and moves through a thermal expansion valve. When it crosses the valve, the refrigerant is decompressed and drops in temperature. The now-cold refrigerant is then piped through the coils of another heat exchanger, where interior air transfers its heat and is cooled. The refrigerant is then cycled back to the compressor pump and the cycle starts again.
Vapor compression refrigeration isn’t the only game in town, however. Other technologies, like absorption refrigeration, accomplish the same task using a different method. Rather than using an electrically driven pump to compress a refrigerant, absorption chillers use a heat source to condense refrigerant. In both cases, the evaporation of a refrigerant is used to carry heat away from indoor air.
Absorption refrigeration isn’t as energy efficient as vapor compression refrigeration. However, in industrial environments that have a large source of heat, like power plants, it makes sense. Since the heat is going to get vented to the environment anyway, it can be put to work driving this type of air conditioning system.
Typically, absorption chillers are large and expensive when compared to the more common refrigeration technology. The economic case is that they pay for themselves over time by saving electricity. However, they have not had much of a role to play in residential air. A typical home does not have a ready source of waste heat – while it does have a ready source of electricity.
In absorption chillers, an evaporated refrigerant adheres to a solid surface. The refrigerant is usually a water solution. For the system to work well, a large surface area is needed. The large amount of surface area makes absorption units too large to be practical for home use compared to vapor compression They are used, though, in off-grid situations where a heat source like propane burners is available. New technology, however, is changing things.
Pacific Northwest National Laboratory has developed improved materials for use in absorption air conditioning systems. Using engineered nanostructures that self-assemble into 3-D shapes, a much-larger effective surface area is created. The end result is a unit 75% smaller that costs half as much as current technology.
In addition, the nanostructures bind more weakly to water molecules than current materials. This means that less heat is needed to drive the refrigeration cycle. It also speeds up the process of absorbing and releasing water molecules. The efficiency gains and lower heat requirements mean that the most common heat source in the world – the sun – could be used to power the air conditioner during the time of the day when it is most needed. Solar water heaters similar to those seen on the roofs of many homes today could provide the heat source needed to keep homes cool.
Today air conditioning units are in 85% of US homes and account for 16% of total residential electricity consumption. And nanotechnology is paving the way to not only reduce costs but boost efficiency. This is not the only sector where nanotechnology is making a significant impact. And in the future we will continue to see more and more developments in this arena. Nanotechnology is one technology sector that that tech investors should be diving into right now. Once these developments become mainstream, early investors could be taking large profits.
The Power Shares Lux Nanotech ETF (NYSE:PXN), which holds a portfolio of nanotech companies, is a pretty good proxy for this sector. But the nanotech sector is a target-rich environment for stock-pickers who can differentiate between “gee-whiz” technologies and those with genuine, large-scale commercial application.
Ad lucrum per scientia (toward wealth through science),