"planning an onshore drilling campaign in the UK"
If this is a (series of wells) and/or if you can collaborate with other license holders to work up a decent drilling program, then this would open up the type of beneficial opportunities you are seeking.
This is assuming well's are of similar design, complexity, capacities, with similar rig rating requirements.
In my view I would then research the North American, Canadian market and bring in a more modern 'fit for purpose' rig to suit.
e.g. Shales Gas and CBM well's being drilled in Pennsylvania has roads, terrain perhaps as difficult that most of UK.
However as can be concluded very modern rigs can overcome these challenges and drill complex wells on very small footprints, with very few people successfully as current operations and projects ongoing will show.
As mentioned if areas are restricted then modern 'pad' land based drilling has advanced and emerged when locations are not always where you want them to be but you can drill multiple wells from one location.
As a starter, I would speak to H&P to see what range of rigs they have and could offer for UK drilling environments. They may already have rigs operating in Europe so mob/de-mob may not be as significant as one would imagine.
Sources - mostly Drilling Contractors - I would use for advice based on my experience in the UK 1976-1983 + 1995-1999:
- Boldon Drilling
- Neddrill Rx: Use "uniheads" uninterrupted safety + 2 days savings as a side benefit
- BenTec Pro Star 2000
- Helmerich & Payne Rx: TurnKey experts
IADC/SPE 11364 Amoco's concept of LAND rig efficiency = (Mechanical + crew) performance.
My guess is that they are not comparing apples to apples - does your US partner have much experience outside the US?
Are they just referring for the time from spud to TD, or the overall time including rig moves, or the cost estimates?
One big difference is the US Regulatory regime is much looser than in the U.K. - and the reduced safety & environmental regulations means they can do things much quicker, albeit with safety and environmental performances that would simply not be acceptable in the UK.
If they are involved in a resource play (e.g. the Eagleford Shale), then they have had literally thousands of wells to optimise their drilling program, plus they use state-of-the-art rigs such as the H&P Flex Rig series which are specifically set up for ultra-fast rig moves and high performance drilling. These types of rigs are usually only made available on multi-year contracts.
A consequence of so many wells may also mean that - for example - mud logging units are not used and E-Logging programs are cut to the bare minimum as they know exactly what information is needed to quantify the wells potential.
A much more developed land infrastructure also means that they can call off equipment in a couple of hours that we would have to carry on the rig - or at least give a much longer call-off notice for.
Other cost-savings for them might be things like the e-logging unit. I imagine in the UK you would have to pay a monthly standby charge of some description, even if it is not actually on the well location? In the US, land utilisation of such equipment means that the service co's can just charge a call-off fee every time it is mobilised. This may also apply to other equipment - e.g. MWD/LWD, PDM's etc.
Finally, it may just be down to drilling difficulties and formation hardness - just in 'bar talk' with friends in the Southern US, although some wells can be extremely challenging, most of the time I hear how quick the drilling is as there are few difficulties (reactive formation, overpressures, losses etc) and a lot of the time (again in the Southern US), it sounds like they are going through the proverbial "whale sh#t and leaves" so can "blow and go".
P.S. One more thing - they may be using OBM (or even diesel based mud!) in their US drilling program, which I'm guessing cannot be done Onshore the UK these days?