Linking in with Martin’s recent post on LED bulbs I recently attended a lecture held by Sandra Rosenthal at Vanderbilt University called “Promise of Nanotechnology: Unique new properties that can be tailored and controlled to solve challenges in our world.” In it, Sandra spoke about research that is ongoing concerning the creation of nano-crystals and there seems to have been some revelations. Now I’m no chemist and when I think of nanotech I mostly think of microscopic robots devouring the Earth so I’ll try to relay what I learned as succinctly as possible.
Let’s start with some basic nano-knowledge (if such a thing is possible). A nanometer to a meter is the same ratio as a meter is to the distance from the Earth to the Sun. So yes, it’s pretty cuss-wordingly small. If you’re looking down a microscope that can see something this small (and I learned these microscopes exist) then you’re pretty much looking at the building blocks of the universe…atoms!
The boffins at Vanderbilt have been creating nano-crystals of various sizes and examining their properties. What they noticed was that the smaller ones emit colours around the ultra violet end of the spectrum and as you create larger crystals the colours shift down the spectrum to the infra-red. In medicine this means you can attach these crystals to specific proteins so that when looking for viruses, tests can be clearer literally days sooner.
But this is all very nice but doesn’t have anything to do with the environment? Well here’s that bit. Currently environmentally friendly LED bulbs emit a rather harsh light but while performing some experiments, Michael Bowers and James McBride of Vanderbilt University accidentally created a batch of nano-crystals containing but 33 or 34 pairs of atoms. When they were illuminated with a laser they emitted a pleasant white light containing pretty much the entire spectrum. So if you were to coat, say a bright blue LED bulb with a thin layer of these crystals you’d have a very illuminating result.
Now for some facts. A standard 40 watt light bulb emits arount 12.5 lumens per watt which makes it about 2% efficient (not very good). Depending on the size, a strip light emits between between 55 and 100 lm/W making them between 8and 15% efficient. Even LEDs are only working around 20% efficiency.
These revelations have opened plans for a new road map that could create new LED based light bulbs running at an efficiency of 90%!! Unfortunately these goals are unlikely to be realised until around 2025 but the subsequent reduction in energy consumption in the U.S. is predicted to save the nation’s household $125 billion!! It could be well worth waiting for.
That being said, the Vanderbilt work was done in 2005 and since then other universities around the world have made similar discoveries and so there now seems to be a healthy race on as to who can turn the science into affordable consumer technology first. In the end the future maybe closer than we think.
If you want to read the online publication from Vanderbilt University then you can find it
here. (It’s pretty easy reading really. Probably easier to read than this jumbled blog was.)
