Thursday, March 27, 2014

Fixing leaks and the Internet of Things

In a previous post, I wrote about when it makes sense the fix leaks (or not) depending on local conditions. Unstated but looming large in that post are some important questions (non-exhaustive list) : 
  • where are the leaks?
  • how big is each leak?
  • what is each leaks' financial cost?
  • what is each leak's environmental cost?
I'll now discuss briefly the issue of finding leaks. Traditionally, we have looked for leaks using a combination of sound, gas, and modeling methods. Today, connected objects offer new opportunities.

Sound and gas methods basically involve surveying the water network to listen for leaks or detect leaking tracer gas. Fixed or mobile listening devices can help triangulate a leaks' location, and tracer gas will leak (or not) downstream of where it has been injected - so the search can be optimized. These methods either reveal little information about the size of the leak, or are limited in physical reach. 

Hydraulic modeling makes it possible to focus the search for leaks. However, hydraulic models need field data to be reliable. Unfortunately, it is very difficult to take an instantaneous picture of a water network unless one has a significant number of sensors that are well-calibrated, functioning, and transmitting all at once. As a result, hydraulic models, while sometimes very precise, do not provide instantaneous information about the location and volume of leaks.

Enter a number of companies (i.e.: Visenti) that have combined the power of connected sensors with Big Data to monitor water networks in real-time to identify leaks and bursts as they happen. Connected water networks can update centralized control centers like SAUR's CPO to make it possible to prioritize leaks and react accordingly. We will shortly see the proliferation of connected objects along water networks, from sensors to meters to valves, in step with the capital campaigns of water utilities. 

Water network sensors must be placed at critical points in physically extensive systems (100s to 1000s of km), often in wet, buried, or even corrosive environments. Changing batteries is expensive, and power is not always available. Sensors therefore must be highly energy efficient and resilient, and their communication protocols must be able to overcome specific challenges. Because utilities are often strapped for cash, a major challenge is establishing an appropriate price point and clearly spelling out the ROI of these investments.   

That said, the Internet of Things, and in particular the Internet of Water Networks, is clearly the way of the future for leakage management - and other aspects of water management too. It will provide that elusive instantaneous picture of what is happening on the network, and allow engineers and technicians to increase their efficiency in reducing leakage rates. 

In a future post, I'll discuss why it's not enough to deploy sensors: utilities have to learn how to use them and transform themselves correspondingly. 

No comments:

Post a Comment