BEIJING — China's unit cost on wind and photovoltaic power projects is expected to drop until 2020 thanks to lower equipment prices and improved design.

The cost of thermal, wind and photovoltaic power generation projects dropped continuously from 2011 to 2015, according to Lv Shisen, vice-president of Electric Power Planning and Engineering Institute.

During the period, the unit cost for thermal power projects declined from the previous five-year period thanks to a 19 percent drop in bank loan rates, Lv said at a press conference.

Meanwhile, equipment costs dropped 12 percent, while engineering costs fell 8 percent.

Hydropower project costs, however, rose as the locations of such projects had moved upstream and to high altitude areas, where both the engineering difficulties and environmental protection costs increased.

"There is still room to reduce costs on thermal, hydropower, wind and photovoltaic power projects as the country's equipment manufacturing and technology level is improving," said Lv.

Amid the government campaign for greener growth, China has reduced the share of coal in its energy mix and built more renewable energy facilities.

By the end of 2020, renewable energy facilities will supply 1.9 trillion kilowatt-hours of electricity, accounting for 27 percent of total power generation, according to the government's 2016-2020 plan for renewable energy.