To save water, get rid of more front lawns

Gary Musser, Las Vegas

Tue, Jul 8, 2008 (2:03 a.m.)

We all should be grateful to people such as Pat Mulroy, general manager of the Southern Nevada Water Authority, and Terry Katzer, a paid consultant to the Water Authority, for helping us take important steps to ensure the future of our water supply.

However, in their commentary on Sunday they write, “No community can conserve enough to survive on only 10 percent of its water supply.” Although that is true, we should pull out all stops to ensure what water we have lasts as long as it can.

My family moved to Las Vegas more than 11 years ago from lush, green Oregon. However, we planted beautiful desert landscaping around the three houses we had built here.

Though some families may need grass in back yards for play, the Water Authority should be more aggressive in keeping as much water in our Lake Mead “bank” as possible.

A simple first step is to dramatically increase incentives for converting grass front yards to desert landscaping (maybe up to 100 percent of the cost) by increasing the costs of water for those who currently have grass front yards. A grass front yard surcharge should fund the conversion incentives.

We live in a desert and there really is something wonderful about seeing the variety and beauty of desert landscaping. Also, it is a reminder that we are all doing our part to save our water for the future.

Discussion: 4 comments so far…

By jfnance32

7/8/08 at 8:24 a.m.

Suggest removal

We are suppose to become the capital state for thermal solar power plants.

Those thermal solar power plants will consume tons of water.

Has Mulroy factored that into the water needs equation?
By JohnF

7/8/08 at 11:14 a.m.

Suggest removal

Mr. Nance,

Do you happen to know what the relative use of water is for solar plants, coal-fired plants, and nuclear plants? It's a serious question; I looked on the web but couldn't find that information anywhere.

I found some information from an Australian government web site, but it only accounts for fossil fuel and nuclear plants. It doesn't mention how much water is used in providing solar-powered electricity.

http://www.aph.gov.au/library/pubs/rn/20...

The range of water use is from zero for air-cooled plants to about 2,700 liters/MWh for nuclear plants. Water-cooled fossil fuel-burning plants (like the three being proposed here in Nevada) use over 1,100 liters/MWh. At about 3.8 liters per gallon, that translates to 289 gallons of water per megawatt hour of electricity produced.

You're right; this is a legitimate concern. If solar power is not less water-intensive than other forms of electric generation we should think twice about it here in the desert.

Anybody have any figures?
By thebs

7/8/08 at 4:34 p.m.

Suggest removal

John,

Take a look at this report titled "Water Demand Projections for Power Generation in Texas"
https://www.twdb.state.tx.us/wrpi/data/s...

Here are a few excerpts:

"Wind, PV solar, and other non-water using renewables can contribute to electricity generation without direct water usage."

"Today, there are no concentrating solar power (CSP) facilities in Texas, but progressive utilities such as Austin Energy are moving toward this concept. CSP plants use mirrors to concentrate the solar radiation onto smaller areas in order to heat a fluid or molten salt. Water is then turned to steam by running it through a heat exchanger with this heated fluid, and that steam is in turn used to generate electricity in a cycle similar to that for fossil and nuclear steam plants. Thus, CSP systems need cooling systems like other thermoelectric power plants. For cooling towers connected to CSP systems, the estimated water consumption is 0.72-0.90 gal/kWh [DOE, 2006]."

Also check out pages 38-39 of the referenced DOE report:
http://www.sandia.gov/energy-water/docs/...

THe DOE report gives a handy comparison of withdrawal/consumtion between energy sources.
By JohnF

7/8/08 at 6:08 p.m.

Suggest removal

thebs,

Thanks!!