Although green energy and carbon neutrality are big news, the United States still uses millions of barrels of oil each day. In fact, the US Energy Information Association reported that, in 2011, the United States consumed 6.87 billion barrels of oil, or about 18.83 million barrels per day. With energy needs like that, the United States is going to need qualified petroleum engineers for quite some time. If you pursue a degree in petroleum engineering, there are a number of fields that you can find yourself working in, depending on your interests.

Production Engineer

The main task of production engineers is to streamline the process of petroleum production. In this task, the engineer is responsible for purchasing equipment to pump oil and gas out of wells. If there is no current equipment that matches the specifications of what is needed in the field, the engineer either will design new equipment or seek other engineers for assistance. Some of the systems that production engineers may design include hydraulic fracturing equipment, tubing, sand control and perforating systems. Production engineers also are responsible for overseeing pumping systems that transfer petroleum out of the ground and into pipelines or storage fields.

Reservoir Engineer

Reservoir engineers determine the viability of an oil field. They estimate how much oil is contained in a field and the best ways to extract it. Using state-of-the-art computers and multicell simulation software, reservoir engineers help to determine exactly where a drill should be placed to reach a field and the type of pipeline that will most efficiently transport the crude. Reservoir engineers also provide forecasts for the production of an oil field. Some fields, for example, may produce best when pumped by a number of shallow wells, while other fields do better with a single deep well. Forecasting production also helps the oil or drilling company know how much money they can expect to earn from a field during a certain period of time.

Drilling Engineer

If you'd like to do more with your petroleum engineering degree than sit behind a desk all day, becoming a drilling engineer is your best bet. Drilling engineers, especially when first starting out, supervise work at drilling sites to make sure that drilling is proceeding according to schedule, safely and within environmental regulations. More than any other types of engineers, drilling engineers work on the day-to-day needs of a drilling site, such as equipment procuring, provisioning and maintenance. Drilling engineers sometimes work with production engineers to assist in equipment design.

Completion Engineer

Completion engineers work hand-in-hand with reservoir, drilling and production engineers to extract the maximum amount of oil from a field. After a field is discovered, completion engineers begin a series of simulations to determine which type of technology, such as acidizing, fracturing, gravity pumping or water injection, works best. A major problem that completion engineers are tasked with on a given field is sand control. Too much sand that leaks into an oil pumping system can wear and break down machinery quickly.