The terms of the deal were not disclosed.
Pacific CEO Jamie Cullen said the purchase would help existing mining customers reduce their carbon footprint and also establish a strong foothold for the company in the fast-developing market for standalone power systems (SPS) and microgrid systems.
"This transaction delivers a talented and cutting-edge team experienced in the integrated renewables market, where decentralisation, decarbonisation and cost reductions are generating significant new growth opportunities," he said.
"We gain home-grown, in-house experience in the integration of renewable energy with traditional remote power generation technology. It's closely adjacent and highly complementary to Pacific Energy's core business."
While Hybrid Systems' major customer in the SPS market is Western Power, Cullen said the increased demand for distributed and clean energy was also providing opportunities for the company's larger scale battery energy storage systems (BESS) to be deployed at remote towns, communities and mine sites, to maximise the use of renewable energy.
Pacific will maintain Hybrid Systems' brand name and support it through funding, resources and facilities to accelerate growth and capitalise on the emerging opportunities in the hybrid power systems market.
Hybrid Systems was formed in 2015 by Aaron Hodges and Mike Hall and recently expanded operations into a new 3000sq.m workshop in Perth, employing 32 people.
Pacific was acquired by QIC for A$422 million late last year.