Best Electrolyte for HHO Generators: KOH vs NaOH vs Baking Soda

Why Electrolyte Choice Matters

The electrolyte dissolved in your HHO cell's water is what allows electric current to flow and split water into hydrogen and oxygen. Different electrolytes produce dramatically different results in terms of current draw, HHO output, and plate corrosion.

Potassium Hydroxide (KOH) — The Best Choice

KOH is the gold standard for automotive HHO generators. It dissolves completely in distilled water, produces high conductivity at low concentrations, and leaves very little residue on plates. Benefits include:

• High conductivity = more HHO per amp
• Minimal foaming or carryover
• Plates stay cleaner longer
• Food-grade versions are widely available

Use 1–3 teaspoons per liter of distilled water and adjust to hit your target amp draw. KOH is caustic — wear gloves and goggles when handling.

Sodium Hydroxide (NaOH) — A Viable Alternative

Commonly sold as lye or drain cleaner, NaOH is cheaper than KOH but slightly less efficient. It produces similar HHO output but creates more foam and deposits on plates over time. For long-term installations, KOH is the better investment.

Baking Soda — Only for Testing

Sodium bicarbonate (baking soda) is cheap and safe to handle, making it tempting for beginners. However, it decomposes during electrolysis, producing sodium carbonate and carbon dioxide. This fouls your plates and introduces CO₂ into the gas stream. Use baking soda only for initial testing to verify your wiring — then switch to KOH immediately.

Distilled Water is Non-Negotiable

Whatever electrolyte you choose, always use distilled water. Tap water contains minerals that deposit on plates, increasing resistance and reducing efficiency. Even filtered water is not pure enough for long-term HHO use.