1 mm^2 PV Cell

[Bret Cahill]

A 100 microwatt PV panel shouldn't cost too much on a production
basis.


Bret Cahill

 

[Bret Cahill]

A 100 microwatt PV panel shouldn't cost too much on a production

Solar calculators are cheap, as are those LED garden lights. A small
polysilicon PV probably costs pennies in production.

What's really surprising -- no one has even commented on this either
-- is the size of the smallest micro electronic item is still as large
or larger than DARPA's insect drones.

It's as though everything sold to consumers _must_ have a key pad,
buttons or switches that require cm^2 of surface area.

How this mentality got grandfathered in is a mystery. Garden lights
have no buttons or size requirements so there is no reason not to
miniturize garden lights for Dollar Store "Glowing Sand" or confetti.

In that case the LED, PV and battery would be printed up on paper and
cost almost nothing.


Bret Cahill

 

[Bret Cahill]

A 100 microwatt PV panel shouldn't cost too much on a production

What's really surprising -- no one has even commented on this either
-- is the size of the smallest micro electronic item is still as large
or larger than DARPA's insect drones.

It's as though everything sold to consumers _must_ have a key pad,
buttons or switches that require cm^2 of surface area.

How this mentality got grandfathered in is a mystery.  Garden lights
have no buttons or size requirements so there is no reason not to
miniturize garden lights for Dollar Store "Glowing Sand" or confetti.

In that case the LED, PV and battery would be printed up on paper and
cost almost nothing.

Different colors could be used to "paint" on the sides of buildings.


Bret Cahill

 

[®]

Different colors could be used to "paint" on the sides of buildings.


Bret Cahill

There's already glow-in-the-dark-paint.

When I type "glow" into Google's search field, the first suggestion to
pop up is "glow in the dark paint".

 

[Bret Cahill]

In that case the LED, PV and battery would be printed up on paper and

There's already glow-in-the-dark-paint.

When I type "glow" into Google's search field, the first suggestion to
pop up is "glow in the dark paint".

It won't glow all night w/o UV or other illumination.

Rail roads won't light up their rolling stock with garden lights
because it would get stolen. Something the size of sand would be too
time consuming to vandalize. Graffitti artists would have to paint
the entire box car to blot it out.

Box car artists might even turn to using the PV_LED-battery sand
themselves. This stuff could be printed up on huge sheets and then
cut into little bits so all they'd need is some spray adhesive and a
leaf blower.


Bret Cahill

 

[Bret Cahill]

A 100 microwatt PV panel shouldn't cost too much on a production

Well, it looks like you have a business plan then.

This is nothing less than the next phase of the microelectronics
revolution.


Bret Cahill


"A long habit of not thinking a thing _wrong_ gives it a superficial
appearance of being _right_ . . .."

-- The infamous incendiary Thomas Paine

 

[Bret Cahill]

In that case the LED, PV and battery would be printed up on paper and

The strontium aluminate stuff is impressive, 10:1 or so better than zinc
sulfide.

People in remote villages could leave sheets of that outdoors and take them in
at night as usable illumination. No batteries to degrade.

I wish there was a really good glow-in-the-dark stuff, but it's probably
physically impossible.

Scaling down garden lights might go as far as originally hoped for the
simple reason PV energy/day ~ surface area, while battery energy /day
~ volume.

Battery box energy density would have to be 25X higher than a garden
light at the 1mm characteristic length.


Bret Cahill

 

[the letter K]

I wish there was a really good glow-in-the-dark stuff, but it's probably
physically impossible.

Just make it into an impedance matching exercise.
Like your imaginary wind-powered car that tapped power off one wheel to
travel downwind faster than the wind that pushed it.

 

[Bret Cahill]

I wish there was a really good glow-in-the-dark stuff, but it's probably

The car wasn't mine and it wasn't imaginary. It was silly.

Fun in the father of invention.


Bret Cahill

 

[Bret Cahill]

In that case the LED, PV and battery would be printed up on paper and

The strontium aluminate stuff is impressive, 10:1 or so better than zinc
sulfide.

People in remote villages could leave sheets of that outdoors and take them in
at night as usable illumination. No batteries to degrade.

I wish there was a really good glow-in-the-dark stuff, but it's probably
physically impossible.

I would ge even further and make it a quasi Law of Thermo

It's the same energy storage problem as micro garden lights. The only
material / battery / super cap that could store enough energy would be
a high explosive much higher than anything except nukes. Li-ion is
probably the limit and has been misleading as to future breakthroughs.

The only thing that would put out enough light all night or keep drive
trains turning would have to be air breathing.

Either you burn something in air or you sit in darkness at night.


Bret Cahill

 

[Bret Cahill]

In that case the LED, PV and battery would be printed up on paper and >> >>> cost almost nothing. >> >> >> Different colors could be used to "paint" on the sides of buildings. >> >> >> Bret Cahill >> >> >There's already glow-in-the-dark-paint. >> >> >When I type "glow" into Google's search field, the first suggestion to >> >pop up is "glow in the dark paint". >> >>The strontium aluminate stuff is impressive, 10:1 or so better than zinc >> sulfide. >> >> People in remote villages could leave sheets of that outdoors and take them in >> at night as usable illumination. No batteries to degrade. >> >> I wish there was a really good glow-in-the-dark stuff, but it's probably >> physically impossible. > >I would ge even further and make ita quasi Law of Thermo > >It's the same energy storage problem as micro garden lights. The only >material / battery / super cap that could store enough energy would be >a high explosive much higher than anything except nukes.Li-ion is >probably the limit and has been misleading as to future breakthroughs.

A single D-cell would get you through the night, powering enough LEDs to read a book or study for school or cook your dinner. And a D cell isn't explosive.

A book light maybe but cooking 200 gms of rice? No way.

Back to the OP issue of scaling down garden lights to coarse sand size ~ 1 mm^3:

The rechargeable AAA cell has a volume of 4300 mm^3 and the PV is 30 mm X 30 mm or 900 mm^2 of photo voltaic.

Reducing the PV area and battery volume by 900 results in a 5 mm^3 battery.

If the battery was printed 1 mm thick on a sheet the battery area would be 2.2 mm X 2.2 mm so if it existed cheap 3% efficiency PV would be just as good at keeping the light on all night.

2.2 mm X 2.2 mm X 2.2 mm cubes would be more like small pebbles than coarsesand and only put out 100 microwatts of light maximum.


Bret Cahill

 

[the letter K]

< I wish there was a really good glow-in-the-dark stuff, but it's probably
< physically impossible.

I'm being really goofy 2nite.


Clitocybe illudens, Omphalotus illudens, Omphalotus olearius [the names
are according to the google. I lost my field manual on macro/microscopic
identification of fungi].

They were previously know by their common name "laughing gem" - the
cultivars I am familiar with do not contain psilocybe - but then again I
said the same thing about Panaeolus subbalteatus ``belted cap''.

Apparently the google says that the Panaeolus subbalteatus is the most
common mushroom ingested for recreational purposes. I would have thought
the Stropharia family to be more popular - but you know how those goofy
mushroom people are.

Anycase, the laugyhing gem has been reported to "glow in the dark"
according the Mycological Association I was foolish enough to join.
There was one case where the mushroom was consumed and it was reported
that the person did not suffer from any toxic effects.

Now I am puzzled. Is the laughing gem a really good glower, or is it
some really good stuff that also happens to glow? More investigation,
please.