> For the complete documentation index, see [llms.txt](https://whitepaper.trustednode.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://whitepaper.trustednode.io/industry-backdrop/pos-blockchains.md).

# PoS Blockchains

PoS consensus blockchains have experienced considerable growth in 2020/2021. According to the Q2 2021 Staked review, there are now 26 PoS coins in the top 100 cryptocurrencies with a combined market cap of over **$450B**, a 150% increase from Q1 2021. Many other PoS projects also entered maturity or obtained significant milestones in 2020/2021. 

The PoS growing popularity is related to environmental and scalability issues surrounding PoW. PoS blockchains require significantly less energy than PoW. The mining of new coins doesn’t require solving energy-demanding computational puzzles like PoW. It happens through staking native coins to validator nodes at no cost. The non-reliance on large amounts of cheap energy and specialized equipment makes PoS less likely to be geopolitically centralized.

![BTC and ETH PoW vs. PoS energy consumption. Source](/files/XsvyZGgTsjRaAxjqhHNu)

There are currently multiple different PoS consensus solutions that differ in their on-chain governance. For example, PoS blockchains require validator nodes to stake specific amounts of native tokens to vote on protocol proposals. In contrast, DPOS and NPOS (delegated and nominated proof-of-stake) allow native token holders to choose validators by delegating coins to their nodes. Only the ‘nominated’ validators can vote on structural changes.

![Popular types of PoS governance protocols. Source](/files/bkxqgAi3oBmFq2gTpA09)