I sure hope it's cheaper than the Rohloff hub, I can't imagine anyone buying these if they are very expensive. I thought I had read that chains and sprockets were pretty efficeint in terms of energy loss.
It's the chain not the internal hub. Rohloff can use either a chain or a belt drive. The belt drive is cheap, and works with other internal hubs (sealed planetary gear system), which are much cheaper (e.g. Shimano, others make them).
Tourers buy them. Money well spent. Just change the oil every year. Less efficient than a clean deraileur drivetrain but those stay clean for about 30 minutes.
Even a muddy chain is unreasonably efficient, to the tune of maybe 85-90% [0].
Having bike toured, keeping a chain halfway clean (or at least not muddy) is not hard. Yes, I see the appeal of an internally geared hub, but marginal differences in efficiency either way would not be high on my list of concerns.
> All of that is working, too, with independent tests showing properly race-prepped drivetrains to be as much as 98% efficient.
> That elusive 2%
> As good as chain optimization has become, there comes a point where there’s no more optimizing left to do, and there are no other options but to rethink the system.
Though, not as in any modern drivetrain but high-end competition drivetrains. At least I imagine it would be with really expensive solutions like Ceramic Speed bearings everywhere.