The three projects planned in Nakhonpathom and Suphanburi provinces are expected to generate 57MW in contracted capacity.
Meanwhile, funds were made available as a part of its public-private partnership program.
ADB private sector operations department senior investment specialist Daniel Wiedmer stated: "ADB is contributing to build a critical mass of successful large scale solar power projects in Thailand, which will give confidence to more investors and banks that solar power is a proven technology and a sound investment."
The funds comprise $52m approved for Yanhee EGCO Holding subsidiary Solarco. A further $33m credit facility will be provided to the company through ADB Clean Technology Fund, under its Climate Investment Fund.
With this financial aid, EGCO is outlining plans to increase its energy capacity to more than 300MW by 2015. Currently it has 9.9MW of biomass and 64MW of solar energy.