How to Capture Solar Energy

The process of splitting water (H2O) into its atomic components (hydrogen and oxygen) using electricity is known as electrolysis. Here's how to do it.


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    Fill a glass (about 3 in./7.5cm diameter) about 3/4 full of tap water.
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    Dissolve a teaspoon of table salt in the water. Salt helps conduct electricity better through water.
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    Place a thin piece of cardboard (a paper plate will work) over the opening of the glass. Poke two thin electrical wires, approximately 1-2 feet/30-60cm long, through the cardboard about 2 inches/5cm apart so that one end of the wire is approximately 2-3 inches/5-7cm submerged in the water.
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    Wrap the other ends of the wires around the positive and negative terminals of a nine-volt battery. Bubbles will soon begin to form on the submerged ends of the wires, hydrogen gas on negative wire and oxygen on the positive wire.
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    To produce sizable amounts of hydrogen (or oxygen) [NOTE: Discretion is advised], continue following these steps; otherwise, you are finished at Step #*You will require, in addition to the previously stated items, a smaller container (a syringe is best) and something with which to suspend the smaller container upside down (tape works adequately).
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    Submerse the smaller container in the larger glass. without removing the glass from the water; or, bringing the opening above the water level of the big glass, flip the smaller glass so that the opening faces toward the bottom of the larger glass. (If using a syringe, simply put the opening into the glass and pull the plunger, filling the syringe with water, and skip to Step 9).
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    Bring the smaller glass' opening toward the water surface, but, again, be careful not to let the opening come out of the water. If done correctly, the smaller glass should protrude from the water's surface, but it will be filled with water (it is being suspended by pressure).
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    Suspend the smaller glass in this position with the clamp/tape/etc.
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    Insert the HYDROGEN (negative) or OXYGEN (positive) wire into the under-water opening of the smaller container.
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    Leave it until the smaller container is full.


  • Sharpen two pencils on both ends and connect the wires to the ends of the two pencils. Place the other ends in the water. This forms larger bubbles, and they are easier to see.
  • Only use DC currents
  • If you have twist ties rip the plastic or paper off of them and they will work.
  • The amount of gasses produced is proportional to the current. The current can be increased by use higher voltages (such as those from a computer power-supply), lower resistances (more salt - but don't overdo it) or by moving the terminals closer together.
  • Get creative! Try adding some dishwashing detergent to the water and you will be able to capture bubbles of hydrogen and oxygen.
  • If you are worried about the danger of producing chlorine gas, you can substitute the salt for baking soda (NaHCO3) which will produce harmless carbon dioxide as a by-product (although the reaction may not be as fast).
  • Using two small graphite rods will work even better. These can be collected by dissecting a non-alkaline battery.


  • Hydrogen gas is very explosive when mixed with oxygen. Do not try to collect large amounts of hydrogen gas and oxygen gas in the same container. Hydrogen is still flammable by itself in air, but not explosive.
  • DO NOT TRY TO BURN THE HYDROGEN YOU ARE CREATING. If any hydrogen is collected in the container you are using, for example a 1gl glass jug, it will only require a small spark to ignite it and cause at the very least, permanent hearing damage, but can also start fires and cause burns.
  • If you feel you absolutely must light oxygen and hydrogen together, be safe - use hearing and eye protection. Try setting up some sort of a remote lighting system such as a sparkler fuse in order to give yourself time to get away.
  • Don't add too much salt (brine solution), otherwise the wire that is producing oxygen will begin producing chloride ions into poisonous chlorine gas. If the water turns, in any form, green, stop the experiment and dispose of the water immediately!

Things You'll Need

  • Small glass
  • Cardboard or paper plate
  • Water
  • Electrical Wire(or number 2 pencils, or a carbon rod from any dry cell.)
  • Salt(or baking soda, or lemon juice,{any acid or base.)
  • -volt Battery(or more,but not least)
  • Smaller container (less than 3 inches in height) OR needle-less syringe (recommended) [OPTIONAL]
  • Small clamping device/tape (DUCT tape works best) [OPTIONAL]

Article Info

Categories: Solar Energy