Small power source for one century

tack:
It's not just the power source you have a problem with, it's the whole device. There is no hard and fast data to prove that any electronics will actually last that long. At the very least you'd need some kind of hermetically sealed container to have a good chance of working preservation, IF you had confidence in a reliable power source.

The chances are that one of the crucial link components will fail way before that 100 year period is up.

Without some form of regular check and maintenance, I'm doubtful you'd get anywhere near the longevity you require.

I'm not so sceptical about the electronic components not lasting that long if the power source life can be solved.
At the refinery I worked at before retirement we still had some equipment at or more then 40 years old that had semiconductor components (diodes, SCRs, transistors, etc) still operational, so I don't think 100 years life output of semiconductors is a automatic show stopper. Especially if it's in some kind of 'sleep' mode that only wakes up say once day or week or month to check the date and then goes back to sleep if 100 years has not elapsed.

Lefty

lefty
I would be surprised if today's consumer electronics lasted more than 20 years. As the old saying goes: "They don't make 'em like they used to."

Shpaget:
lefty
I would be surprised if today's consumer electronics lasted more than 20 years. As the old saying goes: "They don't make 'em like they used to."

Well the project in question is not a typical 'consumer product' now is it? It's designed to 'deep sleep' for 100 years and only then turn fully on and work all it's functions. I think if the power 'problem' can be solved the rest would not be show stoppers.

Lefty

I think the electronics can be challenging (more so from a reliabilty / redundance point of view), but the power sources are more so.

You probably will need to make some assumptions, without spending a lot of money. I would think of a few back-ups, like solar, geo-thermal, mechanism (wind + water), battery + capacitors, etc.

If all the device does is to keep time + go to sleep, its current consumption cannot be that big (ua range).

Solar for the win.

Not in the UK - we haven't seen the damn thing for months.

AWOL:

Solar for the win.

Not in the UK - we haven't seen the damn thing for months.

Doesn't matter, solar for 100 years is a no go. Lighting strike, vandals steals the panel or paints it black, etc. Same for wind generation. The whole assembly must be self contained and sealed up securely. He did state " time capsule " now didn't he?

Lefty

retrolefty:
Doesn't matter, solar for 100 years is a no go. Lighting strike, vandals steals the panel or paints it black, etc. Same for wind generation. The whole assembly must be self contained and sealed up securely. He did state " time capsule " now didn't he?

Lefty

Nuclear it is then.

Seriously now. Where will the device be situated? Can you guarantee that the building/bunker/mountain that will hold it will be there in 100 years?
I'm thinking some sort of thermoelectric device, hooked up to a water flow on one side and something that fluctuates in temperature on other. The batteries would need to be capable of sustaining the device for a few months (which is possible), and would be recharged during summer and winter when there is difference in water/something other temperature.

I wonder could you do it with bacteria somehow? Bacteria + shitload of food for them = heat.

BulletMagnet83:
shitload of food for them

Great technical detail there BM 8)

(PS, where in South of England? I'm from Crawley originally)

That reminds me of the Cold War nuclear land mine, that was going to use chickens to keep the electronics warm...

Maybe cockroaches, and a treadmill?

I'm still working on getting it made a recognised SI unit :wink:

Hampshire, at the moment... until the work runs out anyway! My landlord used to do a lot of work around Crawley.

There are batteries based on tritium that are supposed to (theoretically, not promised) last hundreds of years. Just google "Nano tritium battery"

You need deep pockets though. I think I read somewhere they were nearly $2000 each.

DirtBiker:
There are batteries based on tritium that are supposed to (theoretically, not promised) last hundreds of years. Just google "Nano tritium battery"

You need deep pockets though. I think I read somewhere they were nearly $2000 each.

http://www.betavoltaic.co.uk/citylabs20yearnanotritiumbattery.html these? That dip package looks so cool :smiley:

If the time capsule is buried in the ground then there is the possibility of using a heat pump coupled with some novel alloy and neodymium magnets?

The electronics could be very simple - just count equinox using the alignment of the sun (we don't have a specific date in mind), Stonehenge style.
So charging could be very low current, providing charge is greater than leakage.

Mmm, maybe that is what Stonehenge is? It will pop open soon, spouting confetti....

Or non-electronic, pure mechanical, use rise/fall of groundwater changed by tides to run a clock. Electronics could then be turned on during event day, release chemicals into a battery, and play happy birthday etc. One is only concerned with shelf-life. Bearings etc in the "clock" would only receive two 'ticks' per day, so little wear.

Have a little crank on the outside of the time capsule that turns a generator and charges a battery. Put a sign that reads "Please turn crank".

Someone ought to turn it within 100 years. :smiley:

On a serious note, if you can sleep your processor and it uses 0.35 uA, it would require a 306.6 mAH battery. This assumes a zero internal discharge rate, and some form of battery chemistry that can last 100 years.

John, that is actually an awesome idea :stuck_out_tongue: Crowdsourced power. The one thing you won't run out of in the next hundred years is curious people.

u should go ahead with the perpetual idea :smiley:

I think NASA can make it.the battery that are being used in mars rovers last for almost 20 yrs.if there will be a competition,nasa will make it.

BulletMagnet83:
The one thing you won't run out of in the next hundred years is curious people.

Reminds me of when my brother was little, he made a small wooden box with a slot in the top. He wrote "Insert Coin Here". Of course when ever we had guests over, they all had to insert a coin to see what happens XD