LONDON, England - Formula 1 will look and sound different when the season starts in Melbourne on March 16, with new regulations and the introduction of a turbocharged V6 engine with energy recovery systems.We highlight the major changes for 2014 as the sport goes through its most significant technical overhaul in two decades.POWER UNITWhat used to be called an engine has become something a lot more complicated so the name convention is now "power unit".The previous 2.4 V8s, with kinetic energy recovery systems and capable of 18 000rpm, have been consigned to history and replaced by 1.6 turbopetrol engine limited to 15 000rpm, and two energy recovery systems shortened to ERS.Turbo engines have not been used since 1988.Teams are allowed five power units, comprising six elements, per driver, compared to the eight engines of 2013. A driver will have to start from the pits lane if he uses more than five units, while each additional element above the allocation will incur a 10-place grid penalty.KERS/ERSThe previous kers, activated by drivers, delivered a boost of around 60kW for six seconds. The new ERS does not require the driver to push any buttons and can deliver an extra 119kW for 33 seconds a lap. ERS comprises two electric motors that harvest kinetic and heat energy from the brakes and single exhaust.Whereas a kers failure during a race would merely have put a driver at a disadvantage, ERS failure will be far more dramatic. As a result of ERS, cars will produce more torque at lower revs which puts more stress on the rear tyres and calls for gentler throttle control.EXHAUSTSCars now have one centrally exhaust; there used to be two. This spells the end for “blown diffusers”, where hot exhaust gas was directed over the rear diffuser to generate more downforce. Some teams, such as Red Bull which used the technology to good effect, will be more affected than others.FUEL ECONOMYThe new power units will use 35% less fuel than the V8's as part of a “green revolution” in the sport. Each car has an allocation of 100kg of fuel; it was 150-160kg in 2013 to complete the race without refuelling. There is a also a fuel-flow limiter.Saving fuel will become a top priority for teams as they rely on the power generated by ERS. Driving styles and tactics will have to adapt to the level of fuel consumption.McLaren expect races to boil down to three segments: "An opening charge to establish position; a consolidatory middle stint as engines, fuel levels and temperatures are managed; and a final burst as drivers with the machinery and confidence to push press on to the finish."TRANSMISSIONSThe rules specify eight-speed fixed-ratio transmissions compared to the seven-speed used 2013. In the past teams could pick and choose from 30 gear ratios but in 2014 are limited to same ones with a single change allowed in the season. Further changes will incur penalties.This change means that each gearbox needs to last six consecutive races instead of five.AERODYNAMICSFront wings have become 150mm narrower to reduce the frequency of rear punctures caused by cars clipping those in front. There is no longer a lower beam wing at the rear and the upper part is much smaller.The 2014 regulations require car to have lower noses. The tip (point) of the nose cannot be more than 185mm above the ground; it was 550mm in 2012. The change has been made to prevent cars from being launched into the air during a collision - and to reduce injury from side impacts penetration of another car.As a result, a variety of distinctive noses has been launched in 2014 such as Williams’ “anteater” car. WEIGHTMinimum car weights have increased from 642kg to 691kg to compensate for the heavier power units. Taller and heavier drivers, such as Force India's Nico Hulkenberg, believe the increase is not enough and they are at a disadvantage compared to much smaller rivals such as Williams' Felipe Massa.With every extra kg affectingperformance, expect some drivers to appear much leaner..NOISEThe new power units make a noise softer than that of the screaming V8's. While engines rev at 15 000rpm, the turbo will make its own distinct noise as it spins at 125 000rpm.Renault's Rob White said: "The car will still accelerate and decelerate rapidly, with instant gearshifts. The engines remain high revving, ultra-high output competition engines. Fundamentally the engine noise will still be loud. "It will wake you from sleep,and circuit neighbours will still complain. The sound of the new-generation power units is just different. It's like asking whether you like Motorhead or AC/DC. Ultimately it is a matter of personal taste. Both are still pretty loud in concert."DOUBLE POINTSThe top 1o finishers in the final race of the season in Abu Dhabi will score double points, with the winner taking 50 instead of the usual 25. This controversial move is intended to ensure the title battle is competitive for as long as possible. F1 critics have accused it of being an artificial and unnecessary gimmick.PENALTY POINTS/DRIVER NUMBERSAny driver collecting 12 penalty points in a calendar year faces an automatic race suspension. Drivers have also been allowed to choose their racing numbers, which they will retain for their entire career. In previous years, driver numbers changed according to Constructors' championship standings.