The bicentennial.

OK, so most of you weren’t around then.

But, we- America- put on a hell of a party  back in 1976.  Took  over the entire National Mall in DC to celebrate.  And, we probably were pretty united since we had just escaped the vitriol, chicanery, and criminality of Tricky Dick (Richard Milhous Nixon).  Having our first non-elected President.  Oh, sure, you will tell me that we’ve had lots of Vice-Presidents take over when the President has died- or been murdered.

Except Tricky Dick also had a criminal Vice-President.  Spiro BooBoo (Spiro Agnew) of Baltimore.  Who, like our current President, loved to dabble in criminal conspiracy, bribery, extortion, and tax fraud. So, Which led to a new concept- choosing a Vice President who didn’t go through the system; in this case, it was Gerald Ford.  Which meant within months, he was to become President, when Tricky Dick slunk away when it became clear that he was going to be impeached and removed from office.

Back to the Bicentennial.

With those throngs of visitors, we were going to need a bunch of bathrooms.   Given that this was to be a special event- our bicentennial- a government decision was made to demonstrate some new technology.  Four beautiful (but temporary) buildings replete with toilets, urinals, and sinks.  And everything would be supplied (and resupplied) via total water recycle.

It was obvious that we would need to get rid of a significant amount of water.  After all, urine is 99% water (and feces is also significantly comprised of water).  So, we also incorporated a time-tested (but rarely used) technology in our building- evaporative cooling.  We trickled the excess water over the tops of the buildings (which had black roofs), where the water would evaporate into the atmosphere.   When water evaporates, the latent heat of the water is removed, thereby cooling the remaining water- which is then used to cool the roof of the building, where the heat normally accumulates.  This action, therefore,  cooled the bathrooms- without needing any clunky air conditioner systems.

Which brings up a new device that uses similar principles.  This is the process of “radiant cooling”.  Radiant cooling has taken on new importance in a time when fresh air is practically a health requirement.  Plus, there’s significantly reduced energy consumption involved in this process!  Given that we have 2 billion AC (air conditioning) units (and 1 billion tons of carbon dioxide produced from these units) around the world- with more than 1/2 of them in the US and China, cutting down on the 9% of total energy use in the world is a pretty good thing- both for energy use AND global warming.

The research involved building a ‘cold tube” structure, 10 panels in all, with each panel replete with chilled water (this is where the energy is needed- to keep the water cold) in capillaries.  The 8 foot tall panels were insulated and sheathed in a polyethylene membrane- the cooling involved no condensation, just the infrared transfer of energy.  Basically, the structure looks like a bus shelter.

This has been addressed in a new study found in the Proceedings of the National Academy of Sciences.  This demonstrates- that in a hot and tropical environment- it’s possible to keep cool without recirculating air.  Where was this done?  In Singapore.

Drs. Eric Teitelbaum, Kian Wee Chen, Dorit Aviv, Kipp Bradford, and Forrest Meggers (Princeton); Lea Ruefenacht (Singapore ETH Center); Adam Rysanek  and Denon Sheppard (U Brit Col); plus Jovan Pantelic and Megan Teitelbaum (Berkeley Educational Alliance, Singapore) are the authors of the paper:  Membrane-assisted radiant cooling for expanding thermal comfort zones globally without air conditioning.

One of the key reasons this process works well and with little energy is because dehumidification isn’t effected.  (Air conditioning normally cools AND dehumidifies.) That process is the big energy draw for air conditioning units.  (How much?  How about 60% of the energy requirements for an air conditioning system.)

The key innovation of this research was to demonstrate that the concept works in tropical environments- not just places like Germany (Interpanel serves this market). The study demonstrated two concepts: (1) The low temperature that is  required for radiant cooling in humid environments will form condensation; and,  (2) cold surfaces will still cool adjacent air via convection, limiting the overall radiant-cooling effectiveness.

There still is a problem, however.  This process still relies on the use of hydrofluorocarbons.  You know those “freon” coolants that cause atmospheric heat trapping effects.  But, once we develop new refrigerants, this system can be easily incorporated and, therefore, remove the hydrofluorocarbon problem.