The Benefits of Fracking

I am tired of special interests driving a purely negative discussion on fracking in the US.  Fracking has some very real, tangible benefits to the average person.  What is that benefit in terms average people can understand?  Let's try and make an estimate.

If you look at the historical natural gas price trend, were it not for fracking we would be paying at least $8/mcf for natural gas.  That is still less than Europe.  Instead we are paying around $4 (ignoring the current spike due to an especially cold winter). 

Let's look at the benefit to the average person in the US: We consume 26 trillion cu ft of natural gas per year.  An extra $4/mcf would be $108 billion or $340/person. Man, woman and child.  That $340 a year is equivalent to one Big Mac meal per week per person.  Or a year's worth of Friday-night movie tickets.  Or for the elite intellectuals, $340 is equal to 5 bottles of Philippe Foreau Domaine du Clos Naudin Vouvray Reserve Moelleux or 4 steak dinners at Peter Luger's.

Cheaper natural gas disproportionately benefits the poor.  In the US, 46 million folks live below the poverty line.  Those folks spend about 6% of their money on electricity and natural gas for heating.  They spend about the same for food.  So, if you raise the cost of their fuel and electricity (in a gas-fired plant doubling the fuel cost raises the electricity cost by about 70%), they get quite a bit less to eat. Or, they freeze. 

Lower gas prices are not a promise of good things to come.  This is a benefit that real  folks are getting right now.

How many average people want to give up their fancy wine, steaks, movies Big Macs, or the health of poor families?  That is the inconvenient alternative.

While the average person in the US is getting these benefits, I don't doubt that the societal costs are being borne disproportionately by those living near fracking.  I would not particularly want a gas well next door. I would not really want to share my local road with a bunch of frack trucks and well servicing trucks.   I might be inclined to test my water well a few times. Folks in that situation might make a lot of noise and try to get fracking banned.  They might find very sympathetic, vocal friends in the environmental lobby. But, they wouldn't be average people. They would be a tiny group with special interests. 

Cheaper gas and electricity in the US means we can compete better in manufacturing, have more jobs, and have higher average incomes.  Cheaper gas means less coal, less nuclear, less birds killed in windmills.  

So, before asking folks if they want fracking, tell them what it is going to cost them to not have fracking.

Gas Lift Instability

Someone asked me recently about gas lift well instability.  This is how I learned to determine if gas lift will be unstable, that is deciding if the well will exhibit casing heading.

As far as I know, this was invented by Dick ter Avest with Shell in 1995, but I think Wim der Kinderen was finally able to explain it to me so I could understand it.

This technique was included in WinGLUE software and was a great, simple predictor in the analysis  of  many hundreds of gas lift wells.

Follow the sequence 1-3 to calculated casing pressure at the valve depth vs injection gas rate. 

1) can be calculated with multiphase well performance software and should be a system (inflow and outflow and choke, if any) calculation.  For each injection rate, find the pressure at the lift depth in the tubing.

2) Calculate the dP across the gas lift valve port (or choke, if installed) versus injection rate.  For this purpose, Thornhill-Craver will work well in most cases, especially if operating off of a simple orifice valve.

3) Add 1) and 2) to get 3).  

4) Find the minimum.

Left of the minimum pressure the rates are unstable.  If a rate below that rate is injected, the injection gas will be injected, then deplete the annulus until the production pressure is more than the injection pressure.  Then it will build up until it can inject again, starting the heading cycle again.  If you have it on a rate controller, the rate will average correctly (maybe) but it will be intermitting unintentionally, i.e. casing heading.

Larger valves will have a lower dP across the valve and so the minimum will shift to the right, to higher lift gas rates.

This means that most wells that do not produce on their own have an operational range.  The low end is explained above.  The right side of the curve will rise with injection rate until either a) the maximum injection pressure at the surface is reached, or b) until the pressure re-opens a gas lift valve uphole, which will also cause instability (because now the gas lift rate through one or both valves may fall below the minimum).

Addendum:

By 'larger valves' I mean a larger diameter port or a larger diameter choke.  This would also be the case of a hole (or holes) in the tubing.  Or, multiple open valves.  All of these would serve to reduce the pressure differential between the casing and tubing, and also reduce  the slope of the casing pressure curve (3) in the graph.

Merry Christmas

Merry Christmas and Best Wishes for 2014!

Units Conversion Nomographs

Many of my clients work in different unit systems.  Because I can't remember all the unit  conversion factors, I have carried around a sheet with the factors for many conversions.  That's fine for creating a spreadsheet or computer program, but is not great when listening to a presentation and someone mentions their well rate or productivity index in different units from the ones in my normal frame of reference.  Stopping the presentation to ask "Wait, is that a lot of GOR or not?" spoils the flow of their presentation.

A few weeks ago someone gave me a sheet with x-y graphs for converting a few values.  That was pretty good because I could convert any amount without using a calculator or spreadsheet.  But, such a sheet could only have a few conversions because the graphs took up too much room.

I tried to improve on that by making a set of nomographs for unit conversion.  I hope this will be helpful to you.

If you find an error or want to request another nomograph, tell me in the comments.

Artificial Lift Course in Houston

Last week in Houston I taught for the second time a course on Artificial Lift for Unconventionals.  The other instructors and I improved the course content with more exercises and some fun activities.  We also got a tour of the Weatherford facility in Katy, TX.

I learned more about Unconventional fields, gas well deliquification and various forms of artificial lift.  The students were very enthusiastic.

Austria Again

I recently returned from two weeks running a Produce the Limit workshop near Vienna.  This was the 5th PtL I have run from this office, so the team was very well prepared.  In a field with 90 wells, we managed to find 29 opportunities (recompletions, acidizing gravel packs and some beam pump improvements).  These opportunities are expected to add 20% to the field production, over the next 6 months or so.  With an NPV of over EUR14million, I think we earned our pay for this period.  

k+K hotel, Vienna

Since my regular hotel was fully-booked, I spent the weekend at the K+K hotel in Vienna, on the advice of Tripadvisor.  Very nice hotel and nice staff.  There were several nice restaurants in the area, including Das Heinz, which is just next to the hotel. They were serving Murauer "Nock-Land" dark beer on tap, and it was one of the best I have had--delicious.  I got that and a nice, well-aged steak.  Fantastic!

I flew Austrian Airlines, which I have done before.  I swore never to fly them again because of the horrible, painful, terrible seats in business class.  These things are so hard that most of the passengers choose to sit on their blankets.  I only considered flying them again because their website said they had new seats.  They did have nice new seats that were very comfortable.  The cushion is filled with air, so sitting on it is a bit like sitting on one of those exercise balls, but not in a bad way.  I wonder how long they will last before popping.

The rest of the experience on Austrian is OK, although they do have a 'chef' that helps serve (and, I assume, prepare) meals.  Complete with the chef's hat!  They also have a sky blue interior in the plane and play classical music also.   

This was the 3rd and 4th flight since I got my Global Services membership level on United.  I can't see any difference, except I get to board before the rest of boarding group 1.  I could not even get into the first class lounge in DC on the way back, because I was not flying internationally on United.  Apparently flying on their partner, Austrian was not good enough.  

Yes, these are what qualifies as 'problems' in my life.  I know I'm super-lucky.

AL Course for Unconventional Fields

Just finished teaching (with 4 other experts) a course on Artificial Lift for Unconventional Assets. We put a lot of effort into this over the past six months.  Good to be teaching again. 

Already have the next class lined up for November.  The world of unconventional fields, (oil and gas shales, mainly) is very different.  Artificial lift is the same, but needs to be much more cost competitive and much more flexible than the world of traditional (conventional) fields.  This brings a wide variety of challenges and some creative solutions. New technology will help, but also better, standardized, more automated ways of working must become the norm.