Just one bid was made for a wind farm, energy regulator the Federal Network Agency (BNA) revealed.
The heads of the Federal Solar Industry Association (BSW-Solar) and the German Wind Energy Association (BWE) claimed "artificial competition" between the two technologies is "not expedient".
They added a balanced mix of both technologies was needed to make Germany’s transition to a clean energy system, known as the Energiewende, a success.
Further, as the additional amounts awarded to solar PV will be deducted from future single-technology auctions, tenders planned between 2019 and 2021 are now "largely worthless", they argued.
The BWE and BSW-Solar criticised the "artificial competition" after the BNA released the results of Germany’s second joint-technology tender.
It launched a series of technology-neutral tenders, with wind competing against solar, to determine appropriate financial support requirements for technology-specific auctions, the agency had explained when it announced the first auction in February.
In total, 36 contracts were awarded for solar PV projects with a combined capacity of 201MW.
The weighted average of successful bids increased to €52.70/MWh from €46.70/MWh in April’s tender.
Contracts were awarded with values ranging from €46.70/MWh to €57.90/MWh — up from €39.60/MWh-€57.60/MWh in April.
The price of the lone wind power bid was not diclosed.
The BNA receiveda total of 50 bids with a combined capacity of 307MW — meaning the 200MW allocation was more than one-and-a-half times oversubscribed.
Two bids were excluded "for formal reasons", the BNA added, but it did not explain what these reasons were.