The exploration, production, and environmental biotechnology of petroleum are all topics covered in the Journal of Petroleum & Environmental Biotechnology. Petroleum exploration and production involves extracting hydrocarbons from the earth's underground reservoirs with the aid of several different disciplines, including petroleum geology, drilling, reservoir simulation, reservoir engineering, completions, and oil and gas facilities engineering. Crude oil or natural gas is two of the available forms of the hydrocarbons that were generated. Environmental engineering is a method for integrating science and engineering that can be used to enhance the quality of the environment, including the air, water, and land.

Biofuel is any fuel made from biomass, which includes plant, algal, or animal waste. Biofuel is regarded as a form of renewable energy as opposed to fossil fuels like petroleum, coal, and natural gas since similar feedstock material can be easily supplied. In general, support for biofuel as a cost-effective and ecologically friendly substitute for petroleum and other fossil fuels is strong, especially in light of rising petroleum prices and growing concern over the contribution of fossil fuels to global warming. Due to the implicit destruction of enormous tracts of pastoralist land from food production and the financial and environmental expenses connected with the refining process, many critics voice concerns about the direction of the proliferation of some biofuels. Some long-used biofuels, like wood, can be used straight as the fuel that is burned to create heat. In turn, the heat can be used to operate generators in a power plant to create energy. Many power plants now in operation burn wood, grass or other types of biomass.

Biodiesel, which is derived mostly from oil plants (such the soybean or oil palm) and to a lesser extent from other oil sources, is the alternative and most popular liquid biofuel (similar as waste cuisine fat from eatery deep-frying). The most widely used biofuel in Europe is used in diesel engines and is often blended with petroleum diesel fuel in a variety of ways. Although promising, the commercial development of "third generation" biodiesel produced from algae and cyanobacteria has proven challenging.

Other biofuels include methanol, butanol, and dimethyl ether, which are currently under research, as well as methane gas and biogas, which are produced when biomass decomposes in the absence of oxygen. In addition to offering environmental advantages, biofuels can potentially have significant environmental drawbacks, depending on how they are produced. As a renewable fuel source, plant-based biofuels in theory contribute little to global warming and climate change because the carbon dioxide, a significant greenhouse gas, that is released into the air after combustion has already been absorbed through photosynthesis in the growing plants.