A venture between Toshiba Corp. and Mitsubishi Electric Corp. is more than doubling capacity to produce inverters, a key solar device, tracking growth in Asia and the U.S.

Production of the part, which allows solar power to be fed into grids, will begin at a factory in Texas in late July and at a plant in Yancheng, China, as early as October, said Hidehiko Kikuchi, head of the power electronics systems division at Toshiba Mitsubishi-Electric Industrial Systems Corp. TMEIC has been making inverters at three plants in Tokyo, Shanghai and India.

“We need to become a local player to become global,” Kikuchi said in an interview. “Our idea is to build a factory where there is a big market.”

TMEIC’s annual production capacity will increase to 6.5 gigawatts by next March, from 2.9 gigawatts in early 2014, according to the company.

The 50-50 venture between Toshiba and Mitsubishi Electric has led to an increase in inverter shipments over the last few years, buoyed by Japan’s clean energy incentive program introduced in July 2012, according to Kikuchi.

The maker of inverters for large-scale solar plants saw shipments more than triple to 1.6 gigawatts in fiscal 2013 from a year ago. Shipments rose to 2.5 gigawatts last year.

TMEIC will ship more than 3.5 gigawatts this year, according to company estimates. It is projecting the ratio of overseas shipment will keep rising to 70 percent by fiscal 2018 from this year’s 25 percent with a focus on the U.S., India and China, according to Hisayoshi Kobayashi, who oversees TMEIC’s clean-energy business.

TMEIC ranked fifth in production volume for inverters of all sizes, according to Bloomberg New Energy Finance. SMA Solar Technology AG, the top maker, is seeing its share shrink as rivals such as Sungrow Power Supply Co., ABB Ltd. and TMEIC increase production, according to BNEF data.

Kikuchi said TMEIC wants a 20 percent share of the global inverter market by 2020.