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Electronics company Greenhouse is set to release a lantern that runs on just salt and water. It uses that old favorite of high school science teachers everywhere, electrolysis, in combination with efficient light producing LEDs to provide strong and long lasting light free of conventional batteries.
All you need to do is pour salt water into the main body and you’re off to the races. Inside are two electrodes made of a magnesium rod and a carbon plate. The salt water carries electrons from the magnesium to the carbon creating a current strong enough to run the 10 lights.
Those who can actually remember that boring high school experiment will recall that this will cause the magnesium to gradually break down. This means you can use the lamp for up to 120 hours before you need to replace the rod. Replacement rods are available for 980 yen.
However, the salt water will only be good for about 8 hours before it needs to be replaced. Luckily water is available for free from lots of places and you can probably get your hands on some salt for cheap.
Heck, if you’re near an ocean, you’re good to go. According to the Greenhouse website, water straight from the ocean will power this lantern.
Even if this is a problem the light is included with a water pouch to store extra supplies and there also a USB cable just in case. The whole package should run you about 3,980 yen, which isn’t bad for an environmentally friendly light also useful for disaster situations.
Source: Greenhouse via Weekly Ascii Plus (Japanese)
© RocketNews24
15 Comments
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Maria
That's a pretty good price for a very useful item.
Wakarimasen
Just the kind of gadget that is usefu in addressing carbon usage and energy needs.
omicron
Better use the USB than charging it with salt water. Using salt water will make this 4000 yen device to work for only 5 -straight days then you have to buy a 980 yen replacement rod.
cleo
I imagine you would use the USB normally then in an emergency (eg the next natural disaster) switch to salt water until the power came back on.
BertieWooster
The good thing about this is that for an emergency light, you don't need to keep it charged up or make sure its batteries are good. Stick it in a cupboard and a pet bottle of salt water and forget about it. If the electricity goes out, you have light for a few hours anyway.
120 hours is a long time when you consider that you don't need it on 24 hours a day.
How long do you need artificial light?
From when it gets dark to when you go to sleep.
At that rate, it would last a few weeks.
Of course, during that time, there would be no TV.
People might start talking to each other again!
terebiko
Is it good for 120 hours of use, or for just 120 hours? If the salt water is breaking down the magnesium, I guess you would have to remove the salt water when you aren't using the light, in order to preserve the magnesium, right?
RowanM
Someone should test this.
WilliB
terebiko:
Of course. Separate the electrodes and the liquid, and the process stops. As others have said, this would be a great emergency item. The batteries in your earthquake kit will probably have run out by the time you use it. This thing and bottle of saltwater should remain usable for a very long time.
T-Mack
I like this, I like it alot...People are thinking!
supermonk7
The author clearly isn't thrilled about having to write this article.
Foxie
LOL, is this the joke of today? Volta invented that 200 years ago, every torch battery works that way.
WilliB
Foxi, you are missing the point. It is not a new invention, it is a very useful application for some purposes.
CrisGerSan
Wonderful thanks for sharing a great expansion on some basic physics. Thanks for this.
mikemcfly87
Probably meant that you could gather the required items before the earthquake/nuclear disaster and stockpile them.