# 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) --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://whitepaper.trustednode.io/industry-backdrop/pos-blockchains.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.