Private versus Public Networks for Remote Oilfield Monitoring

The major drivers of the traditional variations of remote production data gathering are cost and presentation. On the cost side are the two extremes of a SCADA system versus a simple call out system. The SCADA system typically employs a dedicated or private network, providing high volumes of information on a near continuous basis at a cost of up to several hundreds of thousands of dollars for spread spectrum radios, radio tower infrastructure, satellite uplinks and complex software to control it all. The ensuing private network allows the owner full use of the available bandwidth but at a significant initial cost and generally a high exposure to single point of failure due to the lack of redundancy in the infrastructure. The radios used will typically generate one or more watts of power for a range of several dozen miles at a cost of several hundred dollars each.

A more efficient alternative is to use a public network for all or a portion of the data collection. Digital cellular modems are available from a variety of vendors at a price point half or less the dedicated spread spectrum radios mentioned above. They are designed to communicate on the major cell carriers existing networks set up to carry voice and increasingly, data traffic to the oil fields. This approach uses less expensive devices and removes the need to construct and maintain a dedicated tower, freeing that capital for other uses and allowing the network to be deployed anywhere within range of a cell tower.

When the field to be monitored has a high concentration of wells in a limited geography a hybrid approach is even better than either extreme of all private or all public infrastructures. This approach uses a set of digital cellular modems dispersed through the field collecting data from several nearby locations via low power, inexpensive radios. The monthly costs are thus reduced without requiring the private tower's costs and exposure to a single point of failure.

In summary,

1. Spread spectrum radio systems require a very large upfront cost
2. Building radio towers in the oilfield increases the risk of failure of the entire system, as there is one single point-of-failure. If high winds damage the tower, or a power outage hits the area, all well sites will be unable to report data to the server
3. Digital cellular network technology is exploding, primarily due to consumer demand. This means the major communications companies are rapidly offering the best, cutting-edge technology to even remote areas of the oilfield, and continued innovation will be funded by consumers. This means reliable, consistent and inexpensive data networks for the oilfield.
4. Using a hybrid approach, companies are using digital cellular and low power, inexpensive radios to provide the real-time data they need to improve their operations and manage their assets effectively.