Minnesota added 2,737 jobs related to clean energy in 2018, a 4.7 percent increase, according to a study released Tuesday.

"Clean energy jobs continue to show strong year-over-year growth, said Gregg Mast, director of Clean Energy Economy MN, a non-profit group that released the study, which was conducted by the industry-led Clean Energy Trust and the business group E2.

In the 12-state Midwest region included in the study, which spans Nebraska to Ohio, clean energy jobs grew 4 percent in 2018.

The clean energy sector accounted for 61,047 jobs in Minnesota last year, led by 46,191 in energy efficiency. Most efficiency-related jobs, which rose 3 percent in 2018, are in occupations where workers spend a portion of their time on projects such as refitting buildings to reduce energy use.

Energy efficiency includes building trades workers involved in heating, ventilation and air conditioning (HVAC). The sector also includes jobs in the manufacture of energy efficient products; installation of efficient lighting systems; and in software development for HVAC.

To calculate employment in energy efficiency, the study's authors used the same methodology as the U.S. Energy Administration, Mast said.

Renewable energy generation was the second-largest clean energy sector in Minnesota last year with 8,098 workers, a 12 percent increase over 2017, according to the report. Sixty-one percent of those jobs were in solar power, while 28 percent were in wind.

The majority of energy generation jobs involve workers who build wind and solar farms and install solar arrays on buildings.

Employers in the overall clean energy sector, including efficiency, project adding 4,400 jobs in 2019, a 7.3 percent growth rate, the study said.