I recently purchased, on a whim, some solar-powered LED garden lights. You hang them up somewhere outdoors, and during the day they soak up all that solar energy. Then as soon as it gets dark they do absolutely fuck all. They glow dimly for about half an hour, then they give up.

It occurs to me, then, that there should be a better option. Manufacture low-power LED lamps on metal spikes, for sticking into the ground. And instead of this solar nonsense, make the spike half out of copper and half out of zinc, with a porous material between the halves. When moisture from the soil penetrates the porous material (and assuming there's some level of electrolytes in the soil water), what you have is a battery, sufficient to create a glow. Add a sensor to turn them off during daylight, and you prolong the life of the metal spike by not drawing current (and hence electrolysing the spike) when it's not needed.
-- MaxwellBuchanan, Jun 09 2017

Tada! Bioluminescent_20Di...ristmas_20Ornaments
Just add a stick... [RayfordSteele, Jun 13 2017]

// as it gets dark they do absolutely fuck all //

We could have told you that would happen. Serves you right for buying Metropolitan Police branded goods. But did you ask ? No, you didn't.

DON'T leave them alone outside. If you do, when you come back, they'll all be huddled together in a quiet corner out of the wind, sucking on ciggies and drinking coffee while bitching about the lack of overtime and watching for a non-white person to give a right kicking before fitting them up for posession.
-- 8th of 7, Jun 09 2017


That was a very smooth segue there, [8th].
-- MaxwellBuchanan, Jun 09 2017


Ah yes. I am a fan of said large Clive, and will investigate.

p.s. what is a "Poundland"?
-- MaxwellBuchanan, Jun 09 2017


// "Poundland" //

A place where proles congregate to enjoy the transient illusion of being meaningful consumers.

Don't worry about it, it's of no relevance to you whatsoever. It's like one of those charity* casino evenings where people "gamble" for modest sums, instead of entire developing countries. It would be funny if it weren't so sad.

*Acting altruistically with no intention of personal gain, for the benefit of the less fortunate. It's a sort of mental illness, more deserving of pity than condemnation. Thankfully, it's rare, and getting rarer.
-- 8th of 7, Jun 09 2017


//charity casino evenings where people "gamble" for modest sums, instead of entire developing countries//

Not necessarily "instead of". How do you think Sturton lost Lesotho? Of course he was out of his head on Snowballs at the time and thought he was wagering Midlothian. Since then, he hasn't been to a single one of the fundraisers for the Bewildered Seamen's and Pot Throwers' Alms Trust.
-- MaxwellBuchanan, Jun 09 2017


// They glow dimly for about half an hour, then they give up.//

You may have sited them in the wrong country.
-- pertinax, Jun 10 2017


What's been invented here is a single-use garden light. Once the stick's dissolved you'd have no way of recharging it.

Much more practical is to run an electrical cable around the perimeter of the garden a few hundred times and connect a few kilowatts of high-frequency power to it. By turning the garden into one half of a giant transformer, the garden lights would only need a small coil to suck some juice out of the massive oscillating magnetic field.
-- mitxela, Jun 10 2017


//Once the stick's dissolved you'd have no way of recharging it. //

That is true. However, I suspect that the electrodes would last for several years.
-- MaxwellBuchanan, Jun 10 2017


Alternatively, go nuclear. A phosphor-coated glass bulb filled with tritium will give off a pleasant green glow for decades.
-- mitxela, Jun 10 2017


Plutonium would be even better - it's in abundant supply, it's a solid rather than a gas, it's an intense alpha emitter, and it has a long half-life.
-- 8th of 7, Jun 10 2017


Yes, it will be great to have radioactive glowing sticks in our streets, creeks and lake beds. It will add to the universe's many juxtapositions of beauty and toxicity.
-- wjt, Jun 10 2017


Like blue-ringed octupi, arrow-poison frogs, cone shells and Kim Kardashian ...
-- 8th of 7, Jun 10 2017


Mole treadmills.
-- lurch, Jun 11 2017


I didn't know mole powder could be used as a light source or fuel.
-- pocmloc, Jun 12 2017


if solar lights actually worked you'd have the dawn chorus all feckin' night.
-- po, Jun 13 2017


// mole powder could be used as a light source or fuel //

To [MB], the odour of powdered, toasted mole is a recreational drug ...
-- 8th of 7, Jun 13 2017


If you have moles already, then all you need to do here is fit them up with some metal suits. They can then do their laps around the garden with mitxela's electric cable.

Or, capture a few of those light-illuminating deep-sea creatures. I'm sure they'd look lovely in the garden within a properly-pressurized vessel.
-- RayfordSteele, Jun 13 2017


Actually, it should be possible to engineer some photosynthetic algae that would bioluminesce...
-- MaxwellBuchanan, Jun 13 2017


We have some of those lights, they work nicely. However, they have an LD50 of 1 winter. The cause of death is varied, wind-induced blunt-force trauma and water ingress followed by freeze/thaw being most common autopsy findings. I suspect your problem is a faulty sky. My parents have a similar problem. They solve it by relocating the lights under a Portuguese sky, but this sky is badly lacking in Radio 4. There's no perfect solution.
-- bs0u0155, Jun 13 2017


Oh, [+] BTW... but only if you replace the silly Cu-Zn for a redox pair that fits with common soil deficiencies. Many soils are deficient in potassium, for example, and the average gardener would benefit from the enhanced light given off by plunging a large spike of metallic potassium into wet soil. You don't even need a second electrode, an LED, or the nasty toxic NiCd battery.
-- bs0u0155, Jun 13 2017


// lacking in Radio 4. //

At the end of the day, civilization is a lifestyle choice. "Et in Arcadia ego ..."

// plunging a large spike of metallic potassium into wet soil. //

<gleeful sniggering>
-- 8th of 7, Jun 13 2017


// replace the silly Cu-Zn for a redox pair that fits with common soil deficiencies //

You could call them 'Fertilights'.
-- notexactly, Jun 15 2017


// silly Cu-Zn //

This might seem totally crazy, but you could maybe even enclose the Cu-Zn pair in a sealed canister, and fill it with a liquid electrolyte - then it would work all the time, regardless of soil conditions! You could even make the sealed canister into a replaceable unit, so people could buy new ones when they run out, or even, maybe, apply electrical current to it in order to reverse the process, and "recharge" it!
-- mitxela, Jun 15 2017


That's just sheer fantasy, [mix].
-- MaxwellBuchanan, Jun 15 2017


CMOT Dibbler/Pratchett would be proud.
-- Sgt Teacup, Jun 15 2017



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