Renewable Energy Engineers

Renewable energy sources provided about 13 percent of the electricity generated in the United States in 2015. The renewable energy industry can be broken down into the following sub-industries: wind, solar, hydropower, geothermal, bioenergy, and fuel cell technology. A wide variety of career options are available to engineers. Additionally, many career skills are transferable from one sub-industry to another. The following sections provide an overview of each renewable energy sector and detail career opportunities for engineers in each industry.


According to the American Wind Energy Association, every state in the U.S. has either an operational wind energy project or a wind-related manufacturing facility. In 2015, wind energy made up 35 percent of all renewable energy in the United States, according to the Energy Information Administration (EIA).

The wind turbine is the modern, high-tech equivalent of yesterday’s windmill. A single wind turbine can harness the wind’s energy to generate enough electricity to power a house or small farm. Wind plants, also called wind farms, are a collection of high-powered turbines that can generate electricity for tens of thousands of homes. In addition to development on land, wind projects are also being developed offshore.

The wind industry is very competitive. There are hundreds of companies that manufacture turbines and related components. Companies are constantly seeking ways to make wind turbines more reliable, efficient, and powerful while keeping costs manageable. In order to achieve these improvements, many types of engineers are employed in research and development. Aerospace, civil (with specializations in construction, geotechnical, structural, and transportation engineering), computer, electrical, environmental, health and safety, industrial, materials, and mechanical engineers design and test the turbines.


In 2015, solar energy made up 5 percent of all renewable energy in the United States, according to the Energy Information Administration. Its potential as a major energy source is largely untapped.

There are different ways to turn the sun’s energy into a useful power source. The most common technology today uses photovoltaic (PV) cells. When a PV cell is directly hit by sunlight, the materials inside it absorb this light. Simply put, the activity of absorption frees electrons, which then travel through a circuit. Electrons traveling through a circuit produce electricity. Many PV cells can be linked together to produce unlimited amounts of electricity.

The concentrating solar power (CSP) technologies use mirrors or lenses to focus sunlight onto a receiver. The receiver collects sunlight as heat, which can be used directly or generated into electricity. The four CSP methods used are parabolic trough systems, power towers, parabolic dishes, and compact linear Fresnel systems that concentrate thermal energy to power a conventional steam turbine. Parabolic troughs can produce solar electricity inexpensively compared to the other methods, and they can generate enough power for large-scale projects. Power towers can also generate power for large-scale projects, while parabolic dishes are used for smaller-scale projects. Flat mirrors are used in compact linear Fresnel systems, which allows for more reflectors to be added to a solar array. This technology allows solar infrastructure to use less land surface than other technologies.

Using solar collectors and storage tanks, the sun’s energy can be used to heat water for swimming pools or buildings. Many schools, hospitals, prisons, and government facilities use solar technology for their water use. This technology can also be used for cooling. Desiccant systems remove moisture from the air, thereby making it more comfortable. Absorption chiller systems are the most common solar cooling systems. These systems produce air-conditioning without using electricity.

A building’s design or construction materials can also utilize the sun’s energy for the building’s heating and light through passive solar design or water heating, or with electrical PV cells. 

Solar engineers work in any number of areas of engineering products that help harness energy from the sun. They research, design, and develop new products, or they may work in testing, production, or maintenance. They collect and manage data to help design solar systems. Types of products solar engineers work on include solar panels, solar-powered technology, communications and navigation systems, heating and cooling systems, and even cars. Solar engineers are frequently electrical, mechanical, civil, chemical, industrial, or materials engineers who are working on solar projects and designing photovoltaic systems. Solar engineers with a degree in civil engineering, for example, may work in solar power plant construction. They use their knowledge of materials science and engineering theory to design and oversee the construction of solar power plants and related infrastructure (such as roads, support structures, and foundations). Others with backgrounds in electrical engineering work in solar power plant operations, controlling and monitoring transmission and electrical generation devices. 


In 2015, hydropower energy made up 46 percent of all renewable energy in the United States, according to the Energy Information Administration.

Hydropower uses the energy of flowing water to produce electricity. Water is retained in a dam or reservoir. When the water is released, it passes through and spins a turbine. The movement of the turbine in turn spins generators, and that spinning produces electricity. In "run of the river" projects, dams are not needed. Canals or pipes divert river water to spin turbines.

In addition to hydropower generated via dams or reservoirs, scientists are currently studying several other types of hydroenergy generation techniques. According to the U.S. Department of Energy (DOE), wave energy technologies "extract energy directly from surface waves or from pressure fluctuations below the surface." These waves can be turned into electricity by onshore or offshore systems. Wave energy can be only harnessed in certain areas of the world. In the United States, the northeastern and northwestern coasts offer the best prospects for viable wave-based generation.

Tidal energy involves the harnessing of tides into electricity. According to the DOE, tides can be harnessed only if the difference between high and low tides is more than 16 feet. There are only about 40 places on earth where this is the case, including sites in the Pacific Northwest and Atlantic Northeast. Tidal energy is harvested by using barrages or dams, tidal fences, and tidal turbines.

Ocean thermal energy conversion (OTEC) involves converting the heat energy stored in oceans into electricity. According to the DOE, OTEC "works best when the temperature between the warmer, top layer of the ocean and the colder, deep ocean water is about 36 degrees Fahrenheit. These conditions exist in tropical coastal areas, roughly between the Tropic of Capricorn and the Tropic of Cancer." OTEC has been around for about 80 years, but it is not yet cost competitive with traditional power technologies.

Hydropower engineers design, construct, and maintain hydropower projects. They typically have backgrounds in civil (especially construction, geotechnical, hydraulic, and structural) engineering, electrical engineering, and mechanical engineering.


In 2015, geothermal energy made up 3 percent of all renewable energy in the United States, according to the Energy Information Administration.

Geothermal heat comes from the heat within the earth. Water heated from geothermal energy is tapped from its underground reservoirs and used to heat buildings, grow crops, or melt snow. This direct use of geothermal energy can also be used to generate electricity. Most water and steam reservoirs are located in the western United States. However, dry rock drilling, a process that drills deeper into the earth’s magma, is an innovation that will eventually allow geothermal projects to be undertaken almost anywhere.

Hydraulic engineers, reservoir engineers, and drillers work together to reach and maintain the reservoir’s heat supply. Geothermal engineers with backgrounds in chemical, civil, electrical, manufacturing, mechanical, performance/systems, project, and quality engineering play an important role in plant design and construction, developing the complex mechanical and electrical systems, as well as the power unit systems, that are part of plant infrastructure.


In 2015, bioenergy made up 11 percent of all renewable energy in the United States, according to the Energy Information Administration. Bioenergy can be used to generate electricity and produce heat. It can also be used to produce biofuels, which are used in place of fossil fuels to power vehicles and for small heating applications. Bioenergy can be derived from wood, construction and consumer waste, landfill gas, and liquid biofuels such as ethanol for use in generating electricity, producing heat, and fueling vehicles.

Engineers help design and build bioenergy and biofuels plants. Civil, electrical, industrial, and mechanical engineers develop designs for plants and process equipment using computer-aided design and computer-aided industrial design software. They work closely with architects, developers, business owners, construction crews, and others to make sure the work is done according to specifications.

Fuel Cell Technology

Until recently, all motor vehicles were powered by gasoline and internal combustion engines. While effective and reliable, these systems cause considerable pollution—especially with the increasing number of vehicle owners in the world. Manufacturers have developed cleaner power options for vehicles such as the electric car, or the gas/electric hybrid. The fuel cell is another option currently in development. A fuel cell is a highly efficient device that generates electricity. According to the Fuel Cell and Hydrogen Energy Association, "fuel cells can run on a variety of fuels, including natural gas and hydrogen. Hydrogen is a clean, carbon-free fuel readily available from a variety of sources. When powered by hydrogen, fuel cells emit only water vapor as a byproduct. Fuel cells can run at any time of day and produce nearly zero noise. They are reliable, safe, and never need recharging." In addition to use in powering motor vehicles, fuel cells are used in a wide range of applications, from stationary electricity generation to portable electronics. They are only in the developmental phase in the automobile industry, but are in regular use in markets in which they can provide performance and environmental benefits. These markets include backup power systems, specialty vehicles (such as airport ground vehicles and fork lifts), portable power units, and combined heat and power production.

Fuel cell engineers use their engineering expertise to design fuel cell systems, subsystems, stacks, assemblies, and components. They typically have backgrounds in chemical, electrical, industrial, materials, and mechanical engineering.

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