What is ADA delegation?
Cardano works with a block generation model (a consensus model) based on the amount staked. For this reason its mechanism is called Proof of Stake (PoS). Stake pools are representatives to the protocol for their delegators. By running their servers, a stake pool runs the technical operations that make this rewarding system possible. Missions of a stake pool are keeping high levels of reliability and security, assisting its delegators and helping in spreading the word about Cardano.
How much does it cost?
When you delegate to a pool, you will pay the amount of 2 ADA. This is a small fee but it's important to discourage so called DoS attacks, in which many operations are pushed at the same time to a server or a group of server to make the unusable. By putting a fee, the Cardano protocol highly discourages DoS attacks by making them much more expensive. When changing pool, you'll pay a transaction fee instead (0.17 ADA).
Will my ADA be blocked when I stake?
Absolutely not! Unlike other protocols such as Ethereum, you will always be able to transfer or take all your delegated amount. You can also undelegate, although you will stop receiving rewards. Currently, this is possible with Yoroi wallet only.
What is pool saturation?
The Cardano system is designed to incentivize decentralisation. Achieving this goal in a Proof of Stake system, where ADAs are delegated to pools means reducing the concentration of ADA in a small number of pools. For this reason if a pool has more ADAs delegated than a certain limit, the rewards for all the delegators will be reduced. This limit is defined by the k value and it's currently 64M. If you are in one of these pools, consider moving to a pool with much less stake, consider a small pool.
Why should I delegate to a small pool?
Small pools are pools that have low amounts of stake. Small pools have less luck but higher rewards and so they can be attractive in two ways: first, since the amount of rewards for each block is decided by the blockchain protocol, if a small pool gets a block, its rewards will be shared between a low number of people so they can be high. On the contrary, if a large pool gets a block its rewards will be shared among many people so you will get a smaller value. This is partially compensated by the fact that in a small pool the total stake is lower and so the total number of blocks per year will be lower. But on average per year, small pools will get higher return of stake (ROS) than larger pools.
One of the purposes of Cardano is to assure decentralisation. By having an ecosystem of many indipendent small pools you are also greatly contributing to this purpose.
When will I receive my rewards?
The clock start when you delegate to a pool. You will have to wait for the next epoch (5 days) to be registered and the next to be active (total 10 days). From that moment you will start contributing to the pool, so you can start receiving rewards. If the pool is small, it won't get immediately a block so you will have to wait for its next block. At that point, you will get rewards 2 epochs after the block is minted.
To summarize: you will need 2 epochs to take part into the pool, and you will get rewards 2 epochs after the pool gets a block.
Why is renewable energy important?
We're here for the long run. Cardano is here to stay and Billionaire Pool was setup with the long run in mind. Being sustainable, energy friendly is a key part of this.