Today's superchargers are high-performance, computer-designed and thermally efficient, but they are still based on the same basic design that's been on the market for decades.

New developments, including variable speed units and superchargers for hybrids promise to offer even more benefits, especially as demand for small, powerful and efficient engines grows in the quest to meet regulatory requirements.

Some of these developments, like the variable-speed units, are very close to market, while the electric superchargers are farther down the road and related to more exotic technologies.

Eaton, a leading manufacturer of superchargers, thinks electrically driven superchargers are not ideal for internal combustion engines but is developing the technology for fuel-cell vehicles, according to Automotive News.

Variable speed and advanced-design standard superchargers are ideal for hybrid vehicles as well, according to Eaton, because unlike turbochargers, superchargers are capable of adding significant power at very low engine speeds - maximizing low-end power and efficiency for constant-rpm range-extending engines in plug-in hybrids and enabling better driveabilty and lower usable gears in standard hybrids as well.

Eaton has also been selected to supply Audi with its superchargers, including the new 3.0L TFSI V6 engine. The unit will power the new S4, and employs Eaton's advanced Twin Vortices (TVS) twin four-lobe supercharger to produce 290hp (213kW) and 310lb-ft (420Nm), with more powerful applications expected. The same TVS supercharger technology is also used by General Motors in the 2009 Corvette ZR1 and Cadillac CTS-V.