Intelligent Water Consumption - the Next Frontier for the Smart Grid?

Published: Mon 26 Aug 2013
A blog entry by Christine Hertzog

Contributed by:

Christine Hertzog
Managing Director
Smart Grid Library

Christine Hertzog's Blog

The Rim Fire, a conflagration centered in California’s Tuolumne County, is larger than the city boundaries of Chicago (with its own interesting history about fire.)  This fire threatens critical power and water infrastructure as well as Yosemite National Park and property for thousands of people and businesses.  The Hetch Hetchy Regional Water System delivers water for 2.6 million residents and businesses in the San Francisco Bay Area, including my town in Silicon Valley.  This system also supplies hydropower for the City of San Francisco, and two of three powerhouses in that area are shut down and awaiting inspection along with high voltage transmission lines, serving important city agencies like police and fire stations, City Hall, SF General Hospital, streetlights, and the city’s electrified transit system.  There will be damage to some of the electric grid’s assets.  The water infrastructure appears to be unaffected.

The City has backup plans in place for both power and water.  San Francisco’s Public Utilities Commission spent $4.6B over ten years to upgrade critical infrastructure and build more reliability into their infrastructure and sources of supplies (water and electricity) as well as the transport of them to the city and its water customers stretching down into the northern border of Silicon Valley.

This event raised a couple of questions for me and a compare and contrast exercise.  What if the water system had been damaged to the point that these backup plans go into effect?  Would it limit the amount of water that would be available to my community?  Could residential customers such as myself curtail water usage in the same ways (and as conveniently) as we are asked to curtail electricity usage?  What tools and programs would be available for me to do this?

There is a modicum of awareness about electricity use via plug load technologies that can measure how much electricity is drawn by specific devices, plus years of education about electricity consumption habits.  There’s also work on disaggregation technologies that deliver whole-house metrics by tweezing out various devices’ electricity use.  Utilities have programs that operate with homeowners’ permissions to automatically control selected devices and modulate energy usage.  Appliance manufacturers are planning new models that can receive electricity price signals and modify their operations to suspend certain functions like defrost cycles or ice-making during high price periods.

We’re way behind that curve on technologies and services that can deliver similar capabilities for residential water consumption. In fact, the situation is downright primitive.  Most technologies are still in conceptual stages and seeking funding.  Existing metering solutions have to be clamped to pipelines, which can mean an intrusive and expensive gauge of near realtime consumption.  How many water agencies are discussing creation of Time of Use (TOU) or dynamic pricing for residential water use based on peak and low demand time periods.  Appliance manufacturers may have water-conservative dishwashers and washing machines, but these aren’t built to flexibly respond to signals coming from a water grid.

Few investors see the need to allocate money to water consumption solutions, because as is often lamented with electricity, the prices for water are just too low.   Consumers don’t see the need for metering water or awareness of how much of a household’s water goes to washing dishes versus running showers versus irrigating flowerbeds and gardens.  But many states already experience significant droughts that trigger restrictions on water use for specific purposes, and as climate change impacts regional precipitation patterns, expect to see more need for intelligent water consumption.

While demand response (DR) activities are being discussed as routine programs for consumers with regards to electricity, it’s hard to find similar levels of discussion ongoing about residential water use in the USA.  While we’re planning a future with smart appliances, water-consuming devices are still really dumb when it comes to grid responsiveness.  We’re all really stupid when it comes to water, and that’s a real problem.  We can live uncomfortably without electricity.  We cannot survive without potable water.

The challenges to create a smart water grid are daunting, and as illustrated here, we’re significantly farther back in terms of achieving objectives compared to electricity.  Some of the technology and policy answers may come from agricultural and industrial consumption. Just like electricity, these categories are heavy users of water, and it would be smart to avoid reinventing wheels whenever possible.  Intelligent water consumption has been overlooked so far, but that’s about to change.

Christine Hertzog
Smart Grid Library