Kazakhstan, which now has the ability to meet domestic demand, will soon start exporting between 500,000 and 650,000 tonnes per year.
The investment will address a major issue for the region: the provision of uninterrupted and sustainable power supply to support economic growth and to improve the well-being of the population.
The European Bank for Reconstruction and Development and the Green Climate Fund are backing the largest solar plant built at one time in Central Asia.
The $3.9 billion project is expected to transform the Tajik economy and warm relations with neighbouring countries such as Uzbekistan, Pakistan and Afghanistan.
Russia's claims of shared interests in Central Asian energy deals rings hollow when it comes to the strategic gas industry, observers say.
The US-based company will provide and install equipment to produce base oils in Fergana Province under an agreement with Uzbek joint-stock company Uzbekneftegaz.
The Kyrgyz government and the Asian Development Bank are working to install solar power systems in remote areas of the country.
The project's goal is to provide surplus hydro-electric power from Kyrgyzstan and Tajikistan to Afghanistan and Pakistan during the summer months.
With financial assistance from the European Bank of Reconstruction and Development (EBRD), alternative energy sources will produce 30% of the country's electricity by 2030, predict observers.
More than 240,000 residents in five cities will benefit from better heating and hot water after implementation of the project.