[doikor]

The market is mainly regulated by having some restrictions on pricing by requiring the sellers to be able to prove that their price roughly matches your their costs + some profit margin (to stop a big player from buying all the cheap electricity and relisting it for massive profits) and forcing producers to put money into escrow/buy insurance for the case that they fail to deliver what they sold.

This latter one led the government having to open a line of credit for tens of billions euros last winter when the prices were high just so the actual producers could afford to sell their (historically highly priced) electricity as the money you have to leave in escrow/insurance price is tied to the SPOT price.