Mar 19 2014
Water Kilowatts Don’t Care!
Pat Mulroy, the retired Las Vegas water executive, said when asked if water
was a basic right, “Sure, if you want some water, take your bucket to Lake
Mead and get it.” This blog is not about the philosophy of whether water is
a basic human right or not. We can discuss that later. Ms. Mulroy was
illustrating the point that water, to be useful, must be moved from its
source to the point of use.
In Water Shock’s Afterword I said, “We can transmit energy over thousands of miles; we cannot move water, weighing 8.35 pounds per gallon, very far without incurring huge energy penalties that can only be economical if subsidized by creating massive government debt.”
Most discussions of water fail to talk about the energy costs required to
bring water from its source to the point of use. That’s why, when
desalination or recycling is the subject, the first comment is usually about
how expensive the energy is to produce it. So let’s do some more math. I
realize many people’s eyes glaze over at the mere mention of putting figures
in front of them. What we need, if I may be so bold as to use the Bible’s New
Testament, is an epiphany like Paul had in Acts 9:18 : “Immediately,
something like scales fell from Saul’s eyes and he could see again.”
Currently, costs are as follows for desal and imported water. See this link
by the Otay Water District. http://www.otaywater.gov/otay/page.aspx?g=69
1) 56,000 acre-feet per year for desalination,$2,042/AF;
2) 2013 Wholesale Rate in AF for imported water from all suppliers,$1,310/AF;
3) Recycled water costing using indirect potable recycling (IPR) is
complicated, but it has been estimated to be somewhere in the range of those
two figures above for imported and desalinated water. See this link.
Much of the cost of imported water is the pump energy required to move it
from one place to another. Twenty percent California’s energy usage is
consumed moving water.
The point is if policy decisions about our most precious resource, water,
are made based on price we can expect failed policies as we move toward
water independence. The water policy makers must be guided first by
reliability, and then chose the better solution. IPR or desal. Both use
essentially the same technology. Following that, a whole slew of factors
enters into the decision. All three, desal, imported and IPR will be equally
adversely affected by rising energy prices.
Is IPR a reliable alternative? There are literally thousands of similar
installations world-wide. No question the technology is solid. Take some
time to read this link. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2672392/
It will be a political decision, not a technical one that will carry the day
to bring San Diego County closer to water independence. And who do the
politicians look to for courage? The voting public! But if the voting public
is not well informed, the potential for disaster looms as the drought
If G. Lance Johannsen from Carlsbad is any indication of public sentiment,
our work is cut out for us. His letter to the editor in today’s San Diego UT (3/19/2014) titled, “Misconception over using desal water”, mistakenly says desal is two to three times more expensive than recycled water. He gets credit, however,for favoring recycling over “dumping [wastewater] in the ocean.”
Since a kilowatt doesn’t care whether it moves imported water into San
Diego County or its used to recycle water already in the County, doesn’t it
make more sense to look to reliability and water independence instead of
hoping for the best from water sources hundreds of miles away subject to
natural disasters and capricious courts?
About Alumni at the University of Montana