Lotus just released a concept based on the Toyota Venza where the goal was to trim the fat, ultimately reducing CO2 emissions. Officially, the project was meant to showcase a "viable mass reduction strategy" on two representative models: a 2017 near-term version and a 2020 long-term version.
Comparing the Lotus Venza versus the off-the-lot Toyota Venza, overall mass was reduced by as much as 38% on the 2020 (minus power train) at only a 3% increase in component costs. The 2017 model's mass reduction was 21%. All this was done using processes and tech that should be available and affordable by 2020.