15 Billion Gallons Of Water Could Be Saved By Solar Power In Arizona
A research study has found that using more solar power in Arizona could save 15 billion gallons of water annually. Most of the water used in Arizona is for agriculture, but another common usage is for cooling natural gas, coal, and nuclear power plants. Obviously, operating rooftop solar power does not require such water use.
“He said that if Arizonans increased their use of rooftop solar power to 20 percent of the energy supply from the 1 percent it represents today, the state could save 15 billion gallons of water a year. That’s enough water to serve 90,000 homes, or the population of Chandler,” reported Arizona Central. The article was referencing former Arizona Department of Water Resources Director Herbert Guenther, who was hired by the Alliance for Solar Choice. Currently, the solar power installed in Arizona is saving about 750 million gallons of water a year. (Of course, adding that much solar would also reduce climate change emissions and air pollution.)
Arizona gets about two-thirds of its electricity from nuclear and coal, with natural gas providing about 25%. Hydropower supplies most of the rest, and there is a little solar power. The Arizona Renewable Portfolio Standard requires the state to produce 15% of its electricity from renewables. The Hoover and Glen Canyon dams produce most of the hydropower.
So, could Arizona get enough solar power capacity to generate 20% of its electricity and save 15 billion gallons of water each year? A report from Environment Arizona says it could get to 25%, “Solar PV capacity in Arizona increased at a rate of 142 percent per year from 2010 to 2013. If solar PV installations continue to increase at just one-seventh of that rate (20 percent) annually between 2013 and 2025, Arizona would have enough solar energy to generate 25 percent of its electricity.”
According to SEIA, Arizona has about 2,143 MW of solar power installed currently, which ranks it no.2 in the US only behind California. Politics seems to have been one of the main barriers to expanding solar more aggressively in Arizona, not any technological barriers. Environment Arizona has written that Arizona could have enough solar power to generate well over 300 times as much electricity as it consumes.
Image Credit: ricraider, Wiki Commons
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Putting things in perspective instead of overhyping and sensationalism:
The average purchase price of off-farm water in Arizona is $25.38/acre ft.
15 billion gallons is 46,033 acre-ft and its total cost would be a measly $1.17 Million that the whole of agriculture will save per year. Now how much would those solar PV plus energy storage as replacement for natural gas and coal fired power plant to deliver the same reliability and amount of energy?
Source for price of agricultural water:
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0ahUKEwj_z6rWvKfJAhXMNYgKHYpVBDoQFggjMAE&url=http%3A%2F%2Fwww.ers.usda.gov%2FdataFiles%2FWestern_Irrigated_Agriculture%2FSet3%2F3-11.xls&usg=AFQjCNFA0SD77_U-6VRViuomKHjOJRvEjA&cad=rja
You can’t buy water you don’t have, so there’s that. Can’t eat money, either.
Surprisingly not every thing is about money. If money was the incentive here the Article probably would have referenced it. This is simply a piece of good news in addition to the rest of the reasons to use Solar over Coal Natural Gas or Nuclear generation. Especially in the Southern States water conservation is a big issue already and will be more so in the future.
Thank you for the perspective though. I also found it interesting that 15 billion gallons sounded like a lot until they equated it to 90,000 homes, that’s really not much.
Water is too cheap at 100 gallons per penny, this is why it has been wasted.
I agree. Every time someone says there is a drought or ‘we need to conserve water’ I think to myself that water is stupidly cheap. If water was priced for what it was worth we wouldn’t have to worry about waste.
It is cheap for farmers, but no residential. Farmers grow crops irrigated above ground where water evaporates. Drip irrigation saves water and improves crop yields, but costs money. Cheap water is easier than investment.
You answered the first question popping into my head at the end of the article. Thanks.
Dear Marion: I consider water to be one of my most prized commodities living in Arizona. I used 4,817 gallons of water last month and was charged $8.69 or about .0018 cents per gallon. Even if I just multiplied that monthly cost by 12, it would mean my water service is worth at least $104.28 per year. Now if I considered what an actual acre foot of water would cost in my community for myself and my neighbors it would cost about $586.00.
So for some water customers in Arizona the cost might certainly be $25.38/acre ft as you have stated. However, with the majority of our population now living in cities and urban areas I believe that quoting such a low value is not in the best interest of our society.
Of course all of the above numbers are just meaningless technical noise since they are only the direct costs for a cubic foot of water in two different markets. In my community we pay additional sewer processing fees which are about 400% higher than our water rate. We of course also pay sales taxes on the purchase of the water and even a small percentage for just having a water service. So for my purposes, WATER is very valuable commodity and we should be doing everything we can to encourage everyone to conserve where possible. If that means taking a broader view of what the value of water really is, then I encourage everyone to take that view. I sincerely hope you agree.
With solar power, we don’t have to ruin pristine desert landscape when there are thousands of acres of unsustainable irrigated farmland throughout central Arizona. Those fields could be replaced with solar thermal power stations with storage providing 24/7 dispatchable power. Cover Phoenix area rooftops with PV and they can sell clean power to hungry California.
Red Texas is the wind leader and red AZ could do the same with solar but it’s just a question of will.
Heck forget about covering food production acreage or pristine desert land with solar thermal or solar PV. Just cover our existing parking lots with solar PV. That will give us more than enough power to meet our daytime energy needs. And sooner or later we will master battery technology and my guess is that will happen in about 4-7 years.
I don’t know how cost effective it is to cover parking lots, but I bet the cars wouldn’t get so hot if you did.
I wonder how low the cost could be brought if we had a company or companies actively doing whole parking lot installations.
It wouldn’t be as cheap as utility scale but land costs would be zero and there should be no environmental studies and remediation costs. Travel to work site costs should be lower. And there would be no cost for things like fences and security personnel. Transmission costs would be zero.
Panel arrays could be assembled at ground level and lifted into place with a small crane. The most significant cost over solar farm installation should be the height of the risers.
Covering parking lots is a nice idea. It would definitely help in our AZ summer where 115 is normal.
One of the issues is that the company who owns the lot does not pay the electricity bill. The tenants pay the bill.
As solar continues to get cheaper I’m sure we will see this sort of set up. I for one would drive farther to a mall/store that had covered parking in the summer. Im sure others would feel the same.
Parking lot operator could enjoy another income stream by selling power to the grid. Or selling it to his/her tenants.
Add to that possible sales to the increasing number of EVs that would pay for a charge and they would pay more than the “cost avoidance” that the grid would pay.
Most of those fields in the desert around Phoenix are used to grow cotton or hay and are extremely water intensive and shouldn’t be there in the first place. We will need to use all options for getting off fossil fuel.
Awesome, more water for Saudi Hay farms in Arizona..
http://www.npr.org/sections/thesalt/2015/11/02/453885642/saudi-hay-farm-in-arizona-tests-states-supply-of-groundwater
Good catch, thanks.
Does water used for power-plant cooling get used up? I’m thinking it mostly gets passed through for the cooling, although some evaporates, of course. So if you replace the fossil fuel plants with solar and wind, you don’t necessarily get much additional water supplies. (Generally water is used and reused many times on its way from the mountains to the sea.)
This quote from Wikipedia is for the 3 unit nuclear power plant located just Southwest of Phoenix Arizona [PVNGS[.
“The facility evaporates water from the treated sewage of several nearby municipalities to meet its cooling needs. 20 billion US gallons (76,000,000 m³) of treated water are evaporated each year.[9][10] This water represents about 25% of the annual overdraft of the Arizona Department of Water Resources Phoenix Active Management Area.[11] At the nuclear plant site, the waste water is further treated and stored in an 80-acre (32 ha) reservoir for use in the plant’s cooling towers” END QUOTE.
Therefor the water is not per say used up but is instead evaporated. In this case if you were to eliminate the nuclear plant and replace it with solar there would be no need to evaporate the 20 billion gallons of water that is used to cool the plants nuclear reactors each year. That 20 billion gallons could be used for other purposes like the irrigation of farm land or used for industrial purposes. It can also be further purified and re-injected into the ground water and used later which is what our community does.
Very interesting! Thanks, Tom G.
15 billion is great but it’s 0.6% of 2.5 trillion annual usage…
Arizona farmers apply an average of 5.7 acre feet of water to the 949,000 planted acres annually. Only 25% of those acres utilize sprinkler or drip irrigation which can consistently perform at 85% irrigation efficiency, including a 5%-10% leaching fraction. (USGS, 2005). The precision application systems easily, not even remotely doubtful, pay for themselves in 3-4 years, often even less, depending on markets and crops grown. Why do you think the Saudi’s are moving in?
Governor Ducey recently took an executive decision to form a Water Augmentation Council. How stupid. What he should do is use his Executive power to raise the minimum cost of water for irrigation to $160 per AF in Ag, and to $900 per AF in urban and industrial irrigation (by dual metering). Guess who would move to impeach him? Start at SRP board, who so callously sell farmers water every year for less than $10 per AF.
If the other 75% of farmers were to adopt precision irrigation and scientific irrigation scheduling for water and nitrogen, both of which carry massive embedded energy costs largely externalized costs to society, then the US Geological Survey (2005) data suggests 6.6 million acre feet of water could be left in streams, aquifers, and reservoirs.
So, rather then removing the water from our critical watersheds north of Maricopa, Pinal, and Pima Counties, water could be well-spent propping up drought-stricken forest lands. The health of our watershed functions is paramount. But, to Arizona farmers, being efficient means losing their so-called “water right.” Our silly state government is run by the land and “water rights” holders. By some bizzaro logic, wasting water on our farms is a beneficial use. It’s all crap to any thinking person.
There are many injustices in our country. I have travelled extensively throughout the Southwest and many or most hotels STILL have 5 gallon flush toilets. This is especially true of hotels on indian reservations. And then there are the 1 gpf urinals by the thousands instead of waterless urinals. And of course it is hard to overlook all of water features in Vegas. And why do people STILL insist on watering grass in California, Nevada, Arizona, Utah, New Mexico and Texas. And still more water is evaporated by all of the concrete lined channels transporting water to California and Arizona so why pick on the farmers first. Looks like “we the people” need to get our act together before we start attacking the people who grow our food.
For a short period of time I served on our local Water Conservation Committee and about 5 years ago we spent about $14 million to improve our water treatment facilities and now most of our schools and golf courses use treated wastewater. And our community water conservation programs have resulted in a further 23% reduction of water conservation.
Your desired rate increase on farmers of from $160 to $900 to me to be some type of punitive reverse psychology rate hike technique which for the most part has been shown to be ineffective and will raise the cost of food for everyone which really accomplishes nothing. You do not motivate people by punishing them. That just creates more division between the people and angers everyone involved who need to be working together to accomplish some goal. It is pure insanity for charge some Arizona farmer a high price for water from the Colorado River when the people in California who get their water from that same river and are still watering their lawns. It’s insanity for the Indian tribes to suck water out of the Colorado River to flood alfalfa fields while people are still using evaporative coolers instead of high efficiency AC units. We have had far too much division over the last 8 years or so and it seems that most conversations on the internet sound more like hate speech than people looking for solutions. If you want to create a level playing field that ends up creating an effective water conservation plan for the Southwestern U.S. then EVERYONE from the President on down needs to be involved. The American people once worked together to solve problems. Now it seems we just fight and call people names.
So here are some of my solutions.
1. Build no more coal, natural gas, nuclear or any other type of power plant that uses water to cool the power plant.
2. Remove all Air Conditioning or Heat Pump units from the roofs of homes. Installing AC units on the roofs of homes reduces their efficiency by not less than 10% and results in more energy from power plants.
3. Eliminate the manufacturing of the upright washing machine and only sell horizontal machines. This would save millions and millions of gallons of water
4. Require all pool builders to install an automated pool cover mechanism to reduce evaporation.
5. Start stressing the need to conserve water and the beauty of decorative low water consuming landscaping in every city by promoting decorative rock and low water plants.
6. Begin the manufacturing of only “inverter style” AC/Heat Pump units which are 50% more efficient than old reciprocating or scroll compressor units. This should be combined with number 9.
7. Plan and advertize that water rates for homes with laws will have their water rates increased 10% per year for the next 10 years. These rate increases would begin in 4 years. This does NOT prevent someone from having a lawn if they want one. They are just going to pay more.
8. Meet with all of the Indian tribes and establish reasonable transition plans to better water conservation.
9. Stop the manufacturing of evaporative coolers which can use up to 12 gallons of water per hour. Replace these evaporative coolers with 20-23 SEER High Efficiency AC/Heat pump ground mounted units. The homeowners will end up paying less to maintain a comfortable temperature level in their homes.
Get the point? It’s not just about the farmers! It’s “we the people” who need to make this happen and of course our farmers can become more efficient. But raising their water rate more than 5 times is not what I consider to be a valid solution.