<P> Separate starting devices may be used to start engines in the pits and on the grid . If the engine is fitted with an anti-stall device, this must be set to cut the engine within ten seconds in the event of an accident . </P> <P> The engines, now referred to as power units, are divided into 6 components: the internal combustion engine (ICE); turbocharger (TC); Motor Generator Unit - Kinetic (MGU - K), which harvests energy that would normally be wasted under braking; Motor Generator Unit - Heat (MGU - H), which collects energy in the form of heat as it is expelled through the exhaust; Energy Store (ES), which functions as batteries, holding the energy gathered by the Motor Generator Units; and Control Electronics (CE), which includes the Electronic Control Unit and software used to manage the entire power unit . In 2015, each driver is allowed to use up to four of each component during a season that is up to 20 scheduled races in length; a fifth power unit (and its components) may be used without penalty if more than 20 races are scheduled to take place . A ten place starting grid penalty will be applied for the use of a power unit component used beyond the established allocation; a pit lane start for entire unit changes beyond the limit . </P> <P> From 2010, refuelling is no longer permitted during the race: every car starts with a full fuel load . The 2010 season cars were about 22 cm longer than 2009 cars to accommodate the enlarged fuel tank this necessitated . </P> <P> Formula 1 has contracted a single supplier of tyres since the 2007 season . The supplier (currently Pirelli) supplies five specifications of slick dry - weather tyres (ultra soft, super soft, soft, medium and hard) (Ultra soft being introduced during Monaco 2016), of which two compounds are provided at each race; these are referred to as the "Prime" and "Option" tyres . The distinction between Prime and Option is that the teams are supplied with more sets of the Prime than the Option tyre for use throughout the weekend . Usually the Prime tyre is harder and therefore more durable than the Option tyre, while the Option tyre provides more grip and therefore allows faster lap times on fresh tyres; at some events the selection is reversed, with the Option tyre being harder than the Prime . The combination of longer lasting and faster tyres adds an element to each car's race strategy . Additionally, two wet - weather compounds are provided by the supplier: intermediate and full wet . Each compound is differentiated by a colour - coded band painted around the tyre's sidewall and including the supplier's logo; purple for ultra soft, red for super-soft, yellow for soft, white for medium, orange for hard, green for intermediate and blue for full wet . </P>

Do formula one cars refuel during the race