Somewhere on the plains of Texas is an APG level sensor on an oil production tank. It reads the levels of both the condensate (oil) and the water that is a natural by-product of the pumping process.
Not only does the sensor tell the exact level of both the oil and water (to facilitate their separation), but it also communicates back to the owners via Internet connection.
The tank is nowhere near a standard Internet connection point. So, how do they do it, and how much does it cost?
The least expensive way is to exploit an existing broadband connection within a few miles of the monitoring location. This can be done with 802.11 Ethernet radios in the 2.4-6 GHZ range (ex. ubnt.com). These act as “wire replacers” to several monitoring locations from a single broadband source. Ethernet radios cost as little at $50 per point, and typically need constant power.
Second in cost, but first in convenience, is a cellular router. Radios need a direct line-of-sight, while cellular does not. In addition, these routers rely on cell towers rather than landline broadband sources, and can be solar powered. Our sensors, such as the LOE series, can check tank levels every two hours for a month and use less than 1MB of data, which costs as little as $9.00/month on a cellular network.
If needed, this connection can be shared with Ethernet radios as well. When possible, this increases the use of data per month, but is more economical than individual routers.
Finally, satellite is always available for remote monitoring locations that have neither a near-by broadband source nor a cellular tower. It is the most expensive option of the three (cost varies), and requires a satellite dish and a modem. While it does require more power than cellular router, it can still be solar powered, and the connection can be shared via Ethernet radio.
All of these methods are more than adequate for our remote sensors due to the small data packet size.
Sharing level data over the Internet by remotely monitoring levels of any body of liquid, whether in a tank or a pond is very effective and inexpensive. Remote Internet connections are quite easy to find, and when compared with alternative methods, are very cost-effective.