noun
power generation company
A company that generates electricity, often used in business or energy contexts.
その発電会社は風力発電に力を入れている。
That power generation company is focusing on wind power.
電力会社 is a broader term for an electric power company that may also handle transmission and retail, while 発電会社 specifically refers to the generation side.
Compound of 発電 (power generation) and 会社 (company).