"Take the top of the scuttle panel off that sits just below the wiper arms.. You will then see on the right handside, 3 10mm bolts holding a metal plate on that covers the airfilter box..(this plate looks like part of the rear bulkhead)
Remove the plate and this will give you the access you need to change the filter."
after taking a closer look under the left-hand side plastic cover - there's a lot more to the job:
taking off both wiper arms, both plastic covers, the large plastic cover under the first (risking damaging the front windscreen glass, etc. etc. - although it doesn't appear that technically difficult but it would be very time consuming for just changinge filter (and the 'service book' states that the filter only needs changing at the normal service! - no wonder)
the Renault servicing people must be laughing...all the way to the bank.
On my 1.9dCi I had to remove the battery, battery tray, ECU support bracket and fold the ECU out the way before I could access the filter box. One circlip needs loosening on the filter outlet, one on the inlet and it pulls free from the car. Then 2 screws on the filter box allow you to remove the top and out pops the old filter.
Phew It sounds a lot, but in reality only takes about 10 mins.