Let's not exaggerate. Bitcoin mining increases energy demand and therefore it can't push the cost of energy down. There's a lot of cool things to think about with energy and bitcoin mining, but let's not pretend that mining creates "negative demand" 😃

Systems like Lightning have the potential to replace the existing payments systems, and the existing payment systems probably aren't very efficient. So, it's possible that the net effect of all bitcoin tech - including Lightning and Cashu and so on - is negative

But mining on its own increases energy costs (perhaps by a tiny amount, but still non-negative)