Siacoin is a utility token of the cloud storage platform called the Sia network. Sia is open-source and blockchain-based. The operations take place on Sia's own blockchain. The coin is used to pay for storage rent transactions. The coin is Proof-of-Work-based meaning that Siacoin can be mined. Another use for the coin is trading.
Energi (NRG) is a next-generation Proof of Stake (PoS) cryptocurrency that combines smart contract capabilities, decentralized governance, and a self-funding treasury.