Algae fuel is biofuel derived from algae. Algae cost much, but they offer high yields. As an example, it’s enough to say that algae can produce more oil in a space the size of a garage than a complete soccer field of soybeans.
There are some positive and negative aspects about algae. One which is very important is that algae don’t „touch“ water sources, they use ocean’s wastewater.
If algae would become the only source of fuel in the USA, a field the size of Maryland should be the plant. It would be possible to satisfy all the fuel needs of the whole America.