Hydrogen is a volatile gas. When mishandled, hydrogen is flammable and can lead to deadly explosions.As an investment, hydrogen stocks have often proven similarly dangerous (metaphorically at least). Several leading pureplay hydrogen companies have seen their share prices implode over the past 24 months. Investors could be forgiven for overlooking the whole sector altogether.However, the truth is that hydrogen can be harnessed as a clean carbon-free fuel source which should be a vital part of humanity’s pow ...