Re: Nuclear fusion reactors are very common. They're called 'stars'.
Putting it in context - the world's entire annual production of tritium and deuterium isn't enough to keep ONE 1GW fusion reactor fed for a year
This is one of the fundamental issues with fusion. Yes, duterium is in seawater (nordic hydro, etc) and you can make tritium from lithium but the former is expensive to extract and whilst 7% of all natural lithium is a candidate for tritium production the latter works out at $50,000 per GRAM
(Also, heavy water is relatively dangerous. It turns out that many life processes rely heavily on quantum tunnelling of hydrogen protons and deuterium essentially "doesn't tunnel". This shuts down mitochondria, stops photosynthesis and prevents DNA unzipping, amongst other issues)
Fusion is "the future" but we need to drastically cut carbon emissions NOW, not in 100 years, so waiting around for it to be ready isn't a viable strategy (If CO2 levels get too high then sea level rise or climate change is irrelevant - if raindwater gets acidic enough (carbonic acid) to start affecting plant life then a runaway process becomes unstoppable - this isn't theory, it's happened in Earth's past and took less than a decade to go from "oh shit" to "Dead Dave, everybody's dead. The entire planet's dead, Dave" (Gaspacho is optional)
Biting the hand that feeds IT
