This paper will highlight the economic advantage of using a Hydraulic Diaphragm Electric Submergible Pump in a Powder River Basin Coal Bed Methane (CBM) well with an average daily production of 75MSCF/Day and 100 barrels of water per day and a pump set depth of 650 feet in 7” casing and 1.9” tubing.
HDESP versus Water Well ESP
Summary of Results
This paper will highlight the economic advantage of using a Hydraulic Diaphragm Electric Submergible Pump in a Powder River Basin Coal Bed Methane (CBM) well with an average daily production of 75MSCF/Day and 100 barrels of water per day and a pump set depth of 650 feet in 7” casing and 1.9” tubing.
The operator saved over $19,000 using the HDESP. This does not include power cost savings which are being confirmed. Details supporting the economic summary data are included on the following page.
|
Items in US Dollars per annum |
HDESP |
ESP Pump |
|
Production |
$219,000 |
$209,400 |
|
Repair or Replacement Cost |
$2,500 |
$7,200 |
|
Pulling Cost |
$400 |
$2,400 |
|
Net |
$216,100 |
$199,800 |
|
Savings |
$16,300 |
|
|
Cost comparison* |
$9,525 |
$1,200 |
|
Cost Differential |
$8,325 |
|
Driver to select HDESP
The operator was experiencing short run life with ESP pumps in certain wells due to problems associated with solids and/or scale. In a 12 month period, the ESP pump failed 6 times.
A Hydraulic Diaphragm Electric Submersible Pump (HDESP) was selected to reduce problems associated with scale and extend run times. The HDESP was installed on Aug 3rd, 2004 and pulled Aug 12th, 2005. Even though the unit ran more than one year, the cost summary above includes a pull and repair for illustrative purposes.
Application Review
An operator in the Powder River Basin has over 300 active wells making on average 100 MMCF of Natural Gas per day.
Application Profile
|
Well Type |
CBM |
|
Predominate Production Method |
Water Well type ESP running full time |
|
Well Profile |
Vertical |
|
Average Water Production |
108 BPD |
|
Average Gas Production |
75 MCF/ day |
|
Power Supply |
3 phase, 480V |
|
Surface Controls |
Across the line starter/controller |
|
Tubing Size |
1.9” OD, 2.75lb/ft,1.6” ID |
|
Casing Size: 0 to 600 ft |
7” , 6.1” ID |
|
Under Ream: 600 to 665 ft |
16” |
|
Pump Set Depth |
650 feet |
|
BHT |
65o F |
Production improvement
Over a 12 month period, there was 12 days of downtime associated with waiting on a pulling unit after the ESP failed (average of 2 days per pull).
|
Total downtime over a 12 month period |
12 days |
|
Average Daily Gas Production (per day) |
75 MMCF |
|
Gas Price ($/MCF) |
$8 |
|
Cost of Lost Production per failure (12 days) |
$9,600 |
Pulling Cost
|
Pulling Cost per workover |
$400 |
|
Failures over a 12 month period with esp Pumps in subject well |
6 |
|
Annual cost |
$2,400 |
Power
The HDESP and water well ESP both run continuously in this application and produce the same amount of fluid but the HDESP uses a 3HP motor and the ESP uses a 5HP motor. Assuming both motors are fully loaded, the following table highlights the power cost savings:
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|
|
HDESP |
ESP |
|
Motor size: HP and KW |
3HP = 2.24KW |
5HP = 3.73KW |
|
Yearly Power consumption at $0.07 / KW-HR |
$1,374 |
$2.287 |
|
Power savings with HDESP |
$913 |
|
Replacement Cost
The average replacement cost of an ESP in this area is $1200. The annual replacement cost associated with ESPs on this well was $7200 (6 x $1200)
* = Cost comparison in summary table is for pump only as electric cable and surface controls are similar for both systems.