What does it Cost to Run On-Demand Hydrogen?

The cost is negligible. You will need some potassium hydroxide ($5 worth will last more than a year). You will also have to buy mineral-free (distilled) water. This is readily available at your local grocery store for about $1 per gallon. Considering the average hydrogen generator units use about a gallon of water
per 2,400 miles. (or one litre lasts for about 630 kilometres). On this basis it will cost you around $10 - $20 per year in mineral-free water.

You should ensure you will always have enough water to produce the hydrogen gas that your car needs. Either check water level each time you fill up with petrol. or install a reservoir (with distilled water) so you don’t forget. Then you really only need to full this up every 1,000 miles.

Why do you use distilled water. Minerals leaves behind a muddy substance that can affect how well the generator works.

Rain water has no minerals in it. If you have a dehumidifier, the water it collects is free of mineral. Some city water treatment systems take out minerals, and if yours does, then you can use tap water safely.

Check your hydrogen generator often, to ensure it is clean, and mud free. With distilled water, the amount of maintenance you will need to do is almost nil.