There’s been lots of talk about electric turbocharging - especially from Audi - but 2016 was the year that they actually started to sound real. Essentially, it’s exactly what it says on the tin - a electrically-driven turbocharger that doesn’t rely on exhaust gases to spool up, negating lag (ramp up times are in the 250-millisecond range) and improving efficiency. They can work independently or in the dead zone between demand and boost pressure (handing off to a more traditional turbo further up the rev-range, a bit like the multi-sized double and triple-charging used by some manufacturers), though the bigger ones require hefty 48v electrical systems to work properly.
Interestingly, because the blower doesn’t actually require exhaust gas to get itself going, it’s technically a supercharger rather than a turbo. Expect this tech to go into production cars in 2017.