Let's face it: the world won't sustain if we still keep relying on fossil fuels. Fossil fuels definitely are the most refined and most familiar sources of energy, but deposits are running low, competition is running high, and they negatively contribute to the atmospheric carbon dioxide concentration. Some renewable sources of energy, such as solar, geothermic and hydrothermal, are good alternatives, but not all countries or households have the resources to manage the processes needed to harness the energy.
They also aren't as sustainable or as cost effective as fossil fuels. However, one type of renewable source comes close: biofuel.
Biofuel are made of terrestrial plants (commonly corn, palm or soy) which are processed to produce ethanol. Biofuel is greatly sustainable at the small scale, but as of now, it cannot be used in the global scale due to how much agricultural land and crops are required. But what if we don't need to use important land space to make biofuel? Instead of using terrestrial plants, we can use algae to make biofuel.
Why algae? They are very similar in function to plants. Algae are plentiful in aquatic environments. They are responsible for about 40% of the global carbon fixation (use of carbon dioxide to produce compounds. They don't take up the land, and they can even be used to absorb sulfates and CO2 in wastewaters. All algae also have the capacity to produce high amounts of oil in their biomass. When algal biofuel is extracted, it is almost chemically similar to crude fossil fuel.
The catch to algal biofuel is that it cannot totally replace fossil fuels. Due to how dependent most countries are nowadays to fossil fuel, millions of acres of water must be dedicated to sustain even one large country as the United States. Algal biofuel processing is also relatively new and unpolished compared to fossil fuel processing, but since the crude oils of algae and fossils are chemically similar and require many similar processes, fossil fuel plants should team up with algal biofuel plants.
Algal biofuel may be more expensive than fossil fuel initially, but that is because it is still getting its foundations built. Future studies and scientific funding should both be instrumental in making algal biofuel a market reality. If humans want to still live in a sustainable world in the future, every step towards renewable energy, especially algal biofuels, are a must.