The tender, which is designed to "evaluate the relative competitiveness" of the two sectors, will be run as an experiment to test the advantages and disadvantages of technology-neutral tenders as promoted by the European Union.
Projects between 5MW and 18MW will be selected solely on the basis of "economic competitiveness", the ministry said.
Winners will receive support in the form of top-up payments, while projects including citizen participation will receive a higher tariff. The deadline is 3 September 2018.
Neither the industry nor the regulator CRE is in favour of the move. Development costs of wind and solar are very different, the industry argued.
This means "the result will probably be the selection of solar projects alone," warned Marion Lettry, assistant executive commissioner of trade body SER.
The CRE points out that wind and solar are complementary, whereby "the periods of low production of one can be offset by the other." Putting them in competition "could have an undesirable impact on achieving targets and on the cost of integrating res into the electricity system".