In flexQgrid, the secondary market comes into play in the yellow traffic light phase, which occurs as soon as a potential congestion is forecasted. This offers all households, units and storage facilities in the affected grid area ("cluster") the opportunity to trade on a virtual marketplace despite a restrictive quota and thus also to feed in or consume more power from the grid than the quota specifies.
Of course, no participant has to call his neighbour and say "I would have to charge my e-car, despite the quota. Could you unplug your e-car for a moment so that mine can be charged?". The secondary market runs fully automatically. With the help of artificial intelligence, bids are submitted via the building energy management system ("BEMS") that state, for example, that one participant would definitely like to charge his e-car, but cannot do so because of the quota. If this participant indicates via his BEMS that he might even be willing to pay a little more to exceed the quota, his bid can be matched on the market with the bids of his neighbours. In this way, a storage facility in the same cluster can store a little more and even get some money for it. Of course, the bids are generated fully automatically, sent to the market and matched there.
The secondary market plattform
The secondary market thus auctions off the right to consume or produce more than one is actually allowed to do without unlawfully violating the quota. This eliminates the danger of a grid congestion.
The secondary market is based on the tried and tested merit order principle. The market trades in 15-minute segments and is tested in 2 versions in the project. In the first version, 1 market trading segment is enabled before the quota comes into effect, which is constant for 6 hours. This discrete market is replaced in the 2nd project phase by a continuous market that trades every 15 minutes. In simulations we have already shown that the welfare of the participating agents in the market can be increased by >= 10% through secondary trading. The matching of bids can be optimally solved within a few seconds with up to 100 market participants. The quotas, bids and market results as well as the entire process flow are stored transparently, non-discriminatory, securely encrypted and unchangeable by specially developed Smart contracts on a blockchain .
The interaction of the secondary market with the grid operator and the hardware and software in flexQgrid creates a decentralised method for a dynamic, flexible solution to forecast congestion. More information about the market mechanism and its characteristics will be available in summer in a paper that is still in the peer review process. Be curious when we report more.