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Well an important part of cryptocurrency is a distributed set of fullnodes, see they are scattered globally, connect to different ISPs etc. Each fullnode contains a full copy of the entire blockchain; having many copies scattered all over the world significanty increases the resliliency of the blockchain to issues like natural disasters, government/ISP interference, hacking attemps and so on.
However its no use if all those fullnodes arent online 24/7/365; if we only turn them on in the daytime when we have solar power for example, then we lose a significant amount of the security of the blockchain. Once security is compromised, then who is going to use it; no-one.

So a small low power device like a Raspberry Pi, allows you to stay online 24/7/365 and support the network, for around 3Watts or 72Wh of energy per day. So its a economically and ecologically viable method to build a strong and secure energy efficient blockchain.

Also staking your coins 24/7/365 gives you maximum chance of staking, which in turn should slightly increase your staking rewards through compound interest, versus starting your wallet say once per year.

If you didnt want to try making this yourself, I would be happy to make one for you (at cost) and post it over, DM me on Slack if you like.