First, you can split water into hydrogen and oxygen, using an ELECTROLYZER. In an electrolyzer, hydrogen and oxygen are pulled apart. The hydrogen is attracted to a negatively charged electrode – the cathode. The oxygen is attracted to a positively charged electrode – the anode.

Second, you can strip hydrogen and carbon atoms apart, in a catalytic converter called a REFORMER. You create CO2 emissions in the process, but much less than if you use fossil fuels directly.

Either way, however, you create some pollution. An electrolyzer runs on electricity, which is usually made from fossil fuels. And a reformer extracts hydrogen from fossil fuels.