You may not know this, but Echain network is primary based on the Proof-of-Authority consensus. Validators are chosen and trusted which is a more energy-efficient alternative to PoS because it requires fewer computing resources (less than 10 KWH atm). The next step is to bring proof-of-green to the PoA consensus. To make this concept a reality, validators will run their nodes on non-carbon energy, making Echain completely carbon neutral.
Same as PoA (Proof-of-Authority), PoGA (Proof-Of-Green-Authority) is a consensus system that allows only authorized entities to validate transactions and propagate new blocks to the chain. In this specific cases, validators needs to run their on-chain activities thanks to renewable/green energy. They will be trustworthy, and subject to regular Validators Audits.
The actual energy consumption of the Echain network, both for the testnet and the mainnet, is approximately 5 to 10 KWH.