The first one is KERS – Kinetic Energy Recovering System – which accummulates ‘lost’ energy generated mainly from braking on a battery pack (the same as regular hybrid cars do), flywheel or hidraulic system and provides additional horsepower (up to a maximum of 80 extra horsepower) to the engine when the pilot activates a button placed on the steering wheel. KERS was reintroduced in 2011 after the 2009 start experience that caused some doubts on its cost-benefit advantages (e.g. it increases the car weight – a typical KERS system weighs around 35 kilograms) and led to its suspension in 2010 by all teams’ common agreement. The use of KERS is limited to 6.67 seconds per lap.
The other one was DRS – Drag Reduction System – which reduces aerodynamic drag with the purpose of enhancing overtaking probability. DRS consists on a adjustable flap mounted on the car’s rear wing that can be opened (the flap is closed to create more appropriate downforce to handle corners) by the pilot. DRS can only be activated if the car to be overtaken is within one second of the pursuer at the DRS detection point(s) that exist in each track. The activation point is located a few hundreds of metres ahead of the detection point. DRS is not allowed in the first two laps of a race. Both KERS and DRS are not of compulsory usage by F1 teams.