The "virtual lease operator" has finally arrived, enabling operators to monitor and control production from their computers via the Internet.

Hanna Oil and Gas Co., a small, family-owned independent, operates about 150 wells in the Arkoma Basin. Hanna's four lease operators had been driving at least 1,000 miles (1,600 km) per week each to check volumes and troubleshoot their wells. In the first quarter of 2001, Hanna made the decision to automate 46 producing gas wells in the Arkoma Basin.
The driving force behind Hanna's interest in automation centered around the company's desire to operate its system on an exception basis. The ultimate goal was to reduce the amount of time spent driving to each facility. Combined, Hanna's lease operators were logging more than 200,000 miles (320,000 km) a year driving to well sites to check flows, pressures and overall operational status. Hanna recognized a Web-based automation system would allow them to perform these "health checks" without driving to the field location, saving them significant time and money.
Because Hanna had a significant amount of hardware, software and communication expertise within the organization, the company had the option to develop an automation system in-house or outsource that function to a third party. One of the latter options was eLynx Technologies LLC, www.elynxtech.com, a provider of real-time, Web-based automation services to the oil and gas industry. eLynx monitors everything from electronic flow meters to compressors to condensate and salt water tanks in the field. The company polls the field data back to a central data center, then makes it available to customers via the Internet for a monthly fee.
Hanna and eLynx began by defining the scope of the automation project. The needs Hanna initially outlined were to poll the following data hourly:
• instantaneous gas flow;
• instantaneous pressure;
• instantaneous orifice differential pressure;
• accumulated previous day gas flow;
• accumulated current month gas flow; and
• site alarm data.
In addition, Hanna wanted the ability to remotely collect the monthly, unedited electronic meter gas flow custody transfer files (hourly data, event logs, alarms and configuration files).
Since most of the facilities were in remote areas with no commercial power available, solar power would be used to operate the flow computer as well as the communications equipment. To conserve battery power, it was proposed that the communications only be active during daylight hours and provide hourly updates during the window of availability. The exception would be those critical locations (primarily compressor stations) that would have solar panel capacity to allow for 24-hour-a-day alarm notification.
Based on Hanna's guidelines, a field survey was conducted to determine the feasibility of using radio waves to establish communications with the remote sites. Using global positioning system (GPS) receivers, the latitude, longitude and elevation were noted for each site. eLynx also identified the availability of any existing towers that could be used in the area. Path profile software then was used to determine:
• path distance between a given remote location and its master station;
• minimum remote tower height; and
• estimated signal strength.
Because of the mountainous, tree-covered terrain, four master stations would need to be installed and maintained for the 46 Hanna wells. The master tower locations were to be connected to the eLynx central servers in Tulsa, Okla., via drops off the existing eLynx frame relay system. All data polling would initiate from eLynx servers in Tulsa, where Web servers would also reside to provide secure, 24-hour-a-day access to Hanna. In the end, the results of this survey indicated radio communications were feasible, but at a very high cost per monitored site.
Hanna and eLynx began to explore alternative communications media. Cellular dial-up and cellular digital packetized data were among the options evaluated. These options were eliminated quickly due to the lack of signal strength in the area.
After some discussion, Hanna agreed to evaluate eLynx's newly developed DataDOC device, which uses the cellular telephone system's overhead data channel (Figure 1). This new technology transports data on an underused portion of the cellular network, the digital overhead channels (DOC), which are mainly used to identify, track and verify the rights of roaming cellular phones through all cellular markets. eLynx recognized that data could be transmitted via the DOCs, so the company subsequently developed hardware that could interrogate a modbus RTU device, package the data and ultimately transmit the data via this infrastructure to the eLynx servers in Tulsa. The hardware, DataDOC, is compatible with major flow computer manufacturers such as TotalFlow, Bristol Babcock, Fisher, Flow Automation and Eagle Research, leaving Hanna free to decide on the make, model and features of their flow computers. Since the DataDOC also consumes little power, it can use the standard flow computer battery safely without endangering data integrity or battery life.
Hanna's basic operational field data needs are accommodated using the DataDOC device. Hanna selected the DOC solution because it provided most of the functionality of the radio solution at one-third of the cost. Hanna elected to receive one scheduled poll daily. Between 6 a.m. and 6:30 a.m. each day, the flow computer data is sent from each device to the eLynx servers. Hanna then views the data through a customized Web page developed and hosted by eLynx (Figure 2). This page provides production reports, alarm summaries (alarms are e-mailed directly to cell phones or digital pagers), demand scans and real-time trending of operating parameters. The alarming is configurable by Hanna via its Web page, giving the company the ability to change the recipients of DataDOC alarms at its discretion. As pumper schedules change, Hanna can easily modify its alarm callouts via the password-protected Web page.
Hanna selected eLynx and the DataDOC device based on several anticipated benefits:
• Increased production. Because lease operators can run their routes electronically via the Internet, they can plan for more efficient use of their time by knowing where the trouble spots are before they start their day.
• Alarm notification. With the use of the 24-hour alarm monitoring, Hanna expects a significant increase in compressor run time by allowing a more timely response to down equipment.
• Reduced operating expenses. By reducing unnecessary trips to the field, vehicle expenses will be reduced, which means fewer miles and tires, as well as less maintenance and gasoline.
• More efficient use of employee time. Hanna will be able to operate more leases with the same number of personnel.
• Internet. Having the information available on the Internet enables access to all production data from any location. Pumpers can log on from their homes, the corporate office or field office, and all that is needed is a computer with a Web browser.
• Economics. With technology changing daily and communications devices becoming less expensive with more features, the move to wireless monitoring seemed a logical choice.
Hanna receives 80% of the value of a full-blown radio system at roughly a third of the cost. Company President Bill Hanna expects these benefits to greatly increase productivity and morale for his company, making the work environment more efficient and easier for employees.
The technology
The DataDOC can transmit well parameters up to eight times daily. To compensate for the low polling frequency (compared to a radio-based system), the unit can be configured to provide exception-based, event-driven alarming, which offers tremendous value to a producer through real-time notification of problems in the field. For those situations in which a user wants to know a well parameter instantly without waiting for the next scheduled poll, demand polling is available. Due to the limited bandwidth associated with this technology, the end-of-the-month custody transfer information still will need to be manually downloaded each month - an easy compromise for such a low-cost monitoring solution.
The digital overhead channel and the DataDOC unit fill a specific need in the ever-growing menu of communication options. If a producer needs constant updates throughout the day, a large number of well parameters and end-of-the-month AGA files, the DataDOC is inappropriate. These customers need a radio-based system. At the other end of the spectrum, if a producer only needs a few critical well parameters such as spot flow, previous day's flow and pressure updated once or twice a day, the DataDOC is a perfect fit. A producer receives daily updates and real-time alarming, allowing him the ability to operate by exception - more wells, more efficiently, with fewer people.
DOC technology is being used by several companies in many industries. This low-cost technology was brought to the oil and gas industry because of its ability to communicate in remote areas, although it can be used anywhere. Industry leaders such as Universal Compression, Devon Energy, Metron Gas Measurement, TotalFinaElf and ABB Automation are using this technology to monitor remote field equipment.
The successful implementation of the DataDOC unit prompted Hanna to enter a marketing alliance with eLynx to sell the unit to other producers and pipelines throughout the Arkoma Basin - a prime area for this type of communication.

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