Can the SAND BATTERY solve our energy problems?

Apparently common sand can be used to store heat for long periods of
time , this heat can then be redstributed to businesses and householders
via heat pumps n and piping similar to geothermal systems that are allready
operating in some places !!
The advantages of sand system are that it can operate anywhere that the
sun shines or the wind blows, as the heat needed to heat the sand will be
supplied by both photo voltaic and wind generators !!
The system itself consists of silo full of sand,( silica) which is apparently
a semi-conductor which gets hot if an electric current is passed through
it, temperatures of 500 degrees have been generated in the test system
which is enough to boil water ??
The test system was built by two scandanavian engineers and has been
hooked up to a small community for further development!!
Donkeyman! :+1::+1::+1:

Sounds promising Donkeyman…
:+1:
Man’s (or womans, but it’s usually a bloke) ingenuity knows no bounds…
:sunglasses:

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Glorified storage heater. The whole thing comes down to energy in Vs energy out + losses. For the UK with our population I believe it’s a non-starter.

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I can just imagine every beach being used for storing power and nobody allowed on them. Besides…we have terrible weather anyway, so there’s that…

The ancient Egyptians knew a thing or three about the usefulness of sand!

@The_Artful_Todger , Yeah. there is that aTodge, but themtest rig only
holds 100 tons of sand, l believe silos are built that hold over 2000 tons ?
So economy of scale will add to the efficiency !
BTW, the test rig is also coupled to a data warehouse which supplies constant
warm air from cooling the data banks ?
myself, l am not convinced the electric current can be passed through a
pile of sand ?? or if it can it may need excessive amperage to do so !!
Donkeyman! :thinking::thinking::thinking:

Dry sand is a good insulator where electricity is concerned and so an electrical heating element would be required unless a source of heat was available from elsewhere. Then there is the question of how to convert the heat retained in the sand into electricity unless there was a means to convey the thermal energy (heat) directly to where it would be distributed. Add to that all the losses involved -----

@PixieKnuckles , Yes, the article does mention that it will not be necassary
to use high grade building sand as low grade seems to make no difference
to effeciency !
And maybe salty sea sand will not be suitable for it ??
Donkeyman! :thinking::thinking:

@The_Artful_Todger , The article said that each grain of sand is in fact
small semi conductor that heats up as the current flows thro, and thus each
grain warms up slightly over time, so the whole silo heats up in its entirety
without relying on heat conduction ??
Regarding converting the heat to electricity, l suppose an array of pipes
would pass thro the silo to heat water?Temperatures of 500° C were
mentioned inside the silo,so boiling water is possible !
Donkeyman! :thinking::thinking:

Sand is not a semiconductor.

@The_Artful_Todger , l only quote the article Todgy !!
I found it on google, under Finnish sand battery !!
Donkeyman! :+1::thinking::+1:

Silicon is though Todger, and isn’t sand made up mostly of silicon?
Wiki says…

Sand is a granular material composed of finely divided rock and mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e., a soil containing more than 85 percent sand-sized particles by mass.[2]

The composition of sand varies, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal settings is silica (silicon dioxide, or SiO2), usually in the form of quartz.

Calcium carbonate is the second most common type of sand, for example, aragonite, which has mostly been created, over the past 500 million years, by various forms of life, like coral and shellfish. For example, it is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years like the Caribbean. Somewhat more rarely, sand may be composed of calcium sulfate, such as gypsum and selenite, as is found in places like White Sands National Park and Salt Plains National Wildlife Refuge in the U.S.

Sand is a non-renewable resource over human timescales, and sand suitable for making concrete is in high demand.[3] Desert sand, although plentiful, is not suitable for concrete. 50 billion tons of beach sand and fossil sand is used each year for construction.[4]

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Sand gets very hot on the beach …to hot today for my dog to walk on . Shame the heat can’t be harvested and stored in situ

Yes that’s the problem Ripple, there are many ways to generate electricity (or heat for the use of) but apart from batteries and capacitors, it has to be used as it’s been produced, or it will be lost. Even batteries don’t come without cost. I think storing electricity is more important than producing it. We need to find a way to produce electricity just when the demand is high, and that isn’t usually when the sun is shining or the wind is blowing because we will all be down on the beach…
:sunglasses:

Indeed sand is but not in a form that is accessable to electricity. To extract silicon and refine the stuff from sand is not particularly difficult but what you end up with is silicon. Silicon is NOT a good conductor of electricity, to be used as a semiconductor silicon must be purified to the Nth degree usually by zone refining (Google it) and then “doped” with an impurity — from here it gets complicated not to mention boring! Best Google it for more details.

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Cheers Todger, I’m on my way over there now…
:+1:

@The_Artful_Todger l suppose thats the point of using it ,it is a semi-conductor and so warms up when a current passes thro it ? If it was a
good conductor it wouldnt get so hot !!
It seems to be working in Finland ??
Donkeyman! :+1::grin::grin::+1:

But that’s not how the sand battery works. The sand has to be heated by either an embedded electric element as an electric storage heater is or by an external heat source. It NOT heated by current flow through the sand.

@The_Artful_Todger , Well lve looked at the article again Todge,and it
appears that you could be right ?
The article mentions resistive heating, which l took to mean the sands
resistance to the electricity ??
I did mention my doubts about the amperage required to pass thro the sand?
Donkeyman! :joy::joy::joy: