You still need fees or inflation because you can't force everyone to install a miner-heater. Some people will refuse. Some people will not upgrade it after 5 years. Some people will want to mine in another fork / altcoin.<p>So the fee/inflation is important to pay the additional cost of the miner-heater, and to encourage people to upgrade it.<p>I've seen a few similar projects before. For example <a href="https://techcrunch.com/2018/03/08/qarnot-unveils-a-cryptocurrency-heater-for-your-home/" rel="nofollow">https://techcrunch.com/2018/03/08/qarnot-unveils-a-cryptocur...</a>