Welcome to ESPNF1's live text commentary for the first practice session of the European Grand Prix. We've got 90 minutes of running ahead of us, during which we should get the first inkling of who's going to be quick and who's going to struggle this weekend.

There are plenty of talking points this weekend, but one seems to be occupying the thoughts of the teams more than most. A new ban on switching engine maps between qualifying and the race has been brought in this weekend and there is speculation that it could hit Red Bull hardest and lead to a more competitive Saturday afternoon. Red Bull say they are confident it won't change anything, but it adds an extra element of interest as the weekend develops.

You won't be surprised to hear that the morning sun is blazing down at Valencia and we are expecting a bone dry weekend all the way through to Sunday.

Karun Chandhok is in Jarno Trulli's Lotus for this morning session, Nico Hulkenberg has taken over from Paul di Resta and Daniel Ricciardo is standing in for Sebastien Buemi this morning.

The session is underway and the championship leader Sebastian Vettel is the first man out on track.

This circuit is only used once a year for the grand prix so the track is incredibly dusty and grip levels will be very low.

All the drivers are out on the medium compounds which are making their race debut this weekend. The teams also have the softs available to them this weekend but we won't see those being used until the afternoon session.

The pit lane is especially dusty and as the cars come back to their garages the surface of their slick tyres are covered by a fine layer of dust.

Webber is on track. He had a horrendous accident here last year, but it probably won't even feature in his mind this weekend ... unless he finds himself behind a slow-moving Lotus on the back straight.

Nico Rosberg has set the first time of the weekend with a 2:06.412, but that is by no means representative.

Button set two fast sectors but backed off in the third and came back to the pits. No representative times yet.

Ferrari says: "Fernando and Felipe have already completed their installation laps (2 for Felipe, 1 for Fernando). Nothing specific to report, all OK."

Hamilton, Hulkenberg and Heidfeld are all out on track at the moment.

Renault is conducting some aero tests: "Nick out with some hi-vis paint on the car for installation lap"

Team Lotus is preparing for its first full-speed runs of the day: "Both cars in the garage now. Tweaks being made to both before the first proper runs"

Hulkenberg is now the fastest man on track with a 1:46.302. Schumacher has set a 1:54.397 but was sompleting constant-speed runs down the back straights for the team to try to understand its new aero parts and wasn't anywhere near full speed.

Hulkenberg improves to a 1:43.769.

Hulkenberg has hit the wall on the run down to turn 12. He lost the rear under braking and smacked the concrete wall.

The rear end snapped away from him and that pitched the nose into the wall, which was soon followed by the rear of the car. Paul di Resta won't be too happy as that's his race car, but the damage doesn't look too bad. He will miss out on some data though.

Satyajeet asks: "Any idea how these constant speed runs help understanding aero parts?"

By running at a constant speed the car has a constant flow of air moving over its body and that helps the team understand what is going on from sensors and aero paint they put on the car. It's about as close as they can get to a controlled experiment on track.

Hamilton is out of his car and taking a good look at the rear end. It doesn't look like he plans to be back in action anytime soon, with his overalls tied around his waist.

Maldonado is on a quick lap. He won here last year in GP2 and fancies his chances of scoring some points this weekend. He sets a 1:43.455, which is the quickest so far.

Alguersuari has gone second fastest with a 1:43.576.

Subramaniyan asks: "Hi any updates for Ferrari this week will Alonso rock?"

The F150 Italia has some suspension tweaks that the team is hoping will help it overcome its tyre warm-up problems. They may have some more we don't know about as most teams bring new aero pieces to each race.

Madonado just had a little lock-up going in to turn 12 on the same section of track that Hulkenberg hit the wall.

Chandhok is about to head out for a run in its Lotus: "Karun given his rolling bite point finder, burnout and clutch instructions for his impending departure"

Chantelle asks: "What was the fasted time set in qualifying last year?"

Sebastian Vettel was fastest with a 1:37.587.

In first practice last year Nico Rosberg was fastest with a 1:41.175. That means the drivers found roughly 3.588 seconds between Friday morning and Staurday afternoon.

Chandhok is crawling around the circuit and has been told not to drop below second gear. A real shame as he was hoping to get some solid running in this session but still hasn't set a time.

Ian agrees with Red Bull and Renault that bringing in a ban on qualifying engine maps is a bit odd: "Hi, It seems to me the FIA is worried this years championship is going to be over before mid season. I don't know any other sport that changes the rules after the season has begun."

Mike Gascoynes confirms that Chandhok has a gearbox issue: "Karun has a gearbox problem, looks like lost second gear"

Chandhok says its the end of his session and that he's not having much luck with his Friday morning practice runs this season.

Alonso has gone quickest with a 1:41.239 ahead of team-mate Massa on a 1:41.758.

Lotus confirms that Chandhok's session is over: "That's it for Karun unfortunately, working on the car to get it fixed for Jarno for FP2"

Webber has set a new fastest time with a 1:40.852, 0.387 faster than Alonso.

Schumacher loses control of the rear of his car under braking for turn ten coming off the swing bridge. Grip levels are still pretty low despite some quick times compared to FP1 last year.

The BBC is reporting that Vettel is running with the Silverstone-spec off-throttle blown diffuser to try and get a grip on what it will be like without the gases going through the exhaust when he's off-throttle. He's currently 18th, 3.263 off Webber, but that time difference could also be due to fuel loads.

Mercedes confirms that "grip level very low at the moment" as Schumacher runs wide once more.

Webber has improved to a 1:40.403.

We're seeing lots of little errors from drivers up and down the field but the run-off areas here are big enough for them to get away with it.

Virgin says: "Reports coming that some teams have been picking up bits of glass on tyres so both engineers asking for a check before putting covers on."

Renault is still trying to get its head around these new medium conpound tyres: "Vitaly's out too so both cars on track, learning these new med compound Pirellis, and just how dirty and slippery the track is"

McLaren gives a bit of an insight into its ultraviolet aero paint: "You can run regular paint, or, if you want to hide the results, ultraviolet paint. The secrets are in the details, which we photograph..."

Massa is 14 laps into this session: "Second run for Felipe has just begun, same set of tyres for the Brazilian driver."

Barrichello complains of a "big vibration" when he goes fast.

The BBC is reporting that Sergio Perez is not feeling ill after his first proper run in the car so that should mean he's good to race this weekend.

Renault is talking Petrov through the optimal places on the circuit to use his KERS power boost: "Vitaly being given KERS deployment allocation strategy over the radio, Nick has ride height changes in the garage"

Alonso set the fastest first sector but a couple of mistakes in corner exits ruined his lap and he backed off in sector three.

Kovalainen has set his Lotus mechanics and engineers a challenge: "Heikki says he needs more rear grip, car so far is bouncing and not riding kerbs as well as he'd like. Initial turn-in is okay though"

Hamilton goes fourth fastest with a 1:41.510 but did not use his DRS. The team appear to be simulating race runs this morning as he hasn't been using it throughout the session.

Just ten minutes remaining in this session. Webber, Alonso, Hamilton and Vettel are all out on track.

Petrov is heading back out. He's having a good session this morning with the second fastest time.

Pirelli gives a little insight into tyre usage today: "This afternoon, the drivers are likely to concentrate on the PZero Yellow soft tyre more as they prepare for qualifying."

20 cars are out on track and they have four minutes to try and knock Webber off the top spot.

Perez just had a huge lock-up into turn two but controlled it very well and still made the apex, he's pushing very hard after missing out on a race in Canada ... and a race in Monaco of course.

Lotus is done for the morning with 17 laps from Kovalainen and just two from Chandhok: "Heikki's FP1 programme is finished now. Start preparing the car for FP2"

Glock is pointing towards the wall at turn five. He had a half spin and appear to have stalled. His car is parked across the track and that will bring an end to any competitive lap time in this session.

There's the chequered flag as first practice comes to an end.

Webber finishes on top, over 0.8 seconds up on Petrov and Alonso in second and third. Hamilton was the fastest McLaren driver in fourth and over a second off the lead Red Bull. Vettel was back in 16th but didn't appear to attempt any low-fuel runs during that session.

Thanks for joining us this morning, Make sure you check back in two and a half hours time for the second session when we'll see the first soft tyre runs of the weekend.