Because of the current fuel-based technology of cars, renewable fuels, like biofuels, are quite popular. As I showed in one of my earlier posts, though, biofuels still emit carbon dioxide, a greenhouse gas, upon combustion. In contrast, hydrogen promises to emit no carbon dioxide emissions, becoming the cleanest fuel available. For those with a basic understanding of chemistry, hydrogen, upon combustion, produces, apart from energy, only water. Water is key to life on Earth, and, if the hydrogen is pure, the water will share that purity, which may allow people to drink that water. However, that approach may be impractical or expensive, and scientists probably did not use that idea to promote hydrogen use. On the contrary, the lack of harmful emissions likely contributed heavily to the concept of hydrogen use, and, with time, the fuel may become useful.
Unfortunately, hydrogen power is extremely problematic, as forty-eight percent of all hydrogen production is met with natural gas through Steam Methane Reforming, or SMR, which, unsurprisingly, also produces carbon dioxide. This method, despite its drawbacks, may serve as an effective transition to more environmentally friendly methods of hydrogen production. In fact, researchers have developed a process where solar energy is used to split water into hydrogen and oxygen, which can be combusted later. However, if the costs of this use of solar energy are too high, then the photovoltaic cells I discussed in an earlier post may prove more effective. Additionally, effective hydrogen combustion requires a fuel cell, which is commonly associated with a fuel cell vehicle. Fuel cell vehicles use hydrogen stored in high-pressure tanks, but can also use fuels such as natural gas and gasoline via a "reformer," which converts those fuels into hydrogen. This property may also aid in transitioning to renewable energy, and the high-pressure tanks could be used in other cars for natural gas combustion to significantly lower greenhouse gas emissions.
Ultimately, the fuel cell has remarkably similar properties to the battery of a Plug-in Hybrid, which I have elaborated on in an earlier post. Both technologies can potentially aid in eliminating greenhouse gas emissions, and both grant the world some flexibility in adapting to renewable energy. Each technology serves as a step in a long, winding staircase, but one technology may prove less expensive, which may halt progress on the other technology. However, scientists should research both technologies, despite the higher price in that approach, so if one technology becomes unexpectedly less effective, then the world will not fall behind in technological development, allowing humanity to preserve the Earth without risk, and the Earth is far too precious to risk to chance.
