The crypto tokens (coins) in circulation on each platform can be used as a currency to engage other market platforms as well. For example, in the case of a P2P power-trading platform and a separate reward system for end-consumer behaviour, a user that receives tokens for riding a bike to work instead of using a car could use the awarded credit to buy renewable power produced by a neighbour in the local community. Their level of complexity and the resources needed for implementation vary significantly from case to case. Four use cases are presented in section 3.