Making California Habitable
I would like to solve the water problems in Southern California. I've run a few numbers. I think I can do it! Here' s how.
First off, big industrial plants that take sea water and desalt it are operating in other parts of the world. We start there, because the technology is proven.
Here's a large plant in Saudi Arabia;
It's the world's largest desalination plant. It produces 264 million US gallons per day. The largest desalination plants should be in California because the people in California use more energy than the people in Saudi Arabia.
The Ras al-Khair desalination plant is a hybrid plant that uses heat and electricity to desalt Persian gulf water at a rate of 264 million US gallons per day.
The Saudi plant uses waste heat from the production of 2.6 GW of electricity, and uses a combination of heat and surplus electricity to desalt water.
https://www.water-technology.net/projects/-ras-al-khair-desalination-plant/
California's population uses more energy than Saudi Arabia's population. Yet, California's power industry is a net consumer of water, not a producer of water. California's power industry could be a source of water! That's the opportunity for investors!
Most very large plants uses multi-stage evaporation, permitting the salt is to be recovered. Reverse osmosis plants are energetically more efficient, however, they have a higher capital cost, higher operating cost, due to frequent replacement of reverse osmosis filters, and a shorter life span. You also produce a brine output with RO which must be discharged back into the ocean well away from the ocean intake. The brine volume is added to the fresh water volume in handling water, which has an energy and capital cost as well.
For this reason, in very large installations, like the plant described, multi-stage evaporation is favoured over RO. Though the use of RO on this scale is a testament to the advances in RO technology. So, RO is an up and coming tech. Has been for the past 20 years. It has its place, but it is secondary to efficient evaporation.
The Saudi experience says that with a 2.6 GW electrical output you have 6.5 GW thermal input. The electricity is sold, and the heat is used in a multi-stage evaporator to make fresh water. Unsold electricity fires up the RO plant and adds to the water supply made with waste heat. In this way the heat is mitigated and the power plants become a net water source.
In the Gulf States you typically have gas which is flared since the cost of transport is too high. For local consumption flare gas is captured and burned at low cost. To produce 6.5 GW thermal input you need 481 tons of natural gas per hour.
Now California uses 57 GW of power according to the DOE EIA. The water used to cool these plants is withdrawn from fresh water supplies. It is not reused for public supply. It could be!
Clearly there is a benefit if;
(1) Sea water is desalted using waste heat where feasible,
(2) The desalted water simultaneously cools the plant,
(3) The desalted water is used for public supply,
(4) Waste water is recycled and used to irrigate farms,
(5) Irrigated land is within greenhouses to reduce evaporation,
(6) Irrigation waste is recycled,
What is the impact of these steps?
LA uses 7.3 GW of electrical power. Three times that of Saudi Arabia.
2.2 GW of power comes from the Diablo Canyon Nuclear Power plant. Another 2.8 GW comes from the Moss Landing Power Plant, 2.0 GW of power comes from AES Alamitos Gas Power plant, 1.5 GW comes from the Ormond Beach Power plant.
These are places to start.
So, we make use of the heat in these power plants, to drive a multi-stage evaporator, while cooling the plant and arrange to buy surplus electrical power when available, to drive RO filters, we will produce 22x the output of Ras al-Kahair plant - 5.8 billion gallons per day at a cost of $154 billion which translates to $8.38 per 1000 gallons at typical discount rates.
The California PERS has over $1 trillion in funds that it could bring to bear on a project such as this. They could underwrite a properly structured project.
California uses 38 billion gallons of water per day. 6.6 billion gallons per day is used as cooling water for power plants. This could be reduced to 5.8 billion gallons per day with the installation of more advanced systems using water desalination as a component.
Reuse of this desalted water for human consumption supplies 5.8 billion gallons per day.
So, this subtracts off the 6.3 billion gallons per day is used as the public water supply leaving 0.5 billion gallons per day from fresh water sources.
According to the USGS California uses the following millions of gallons per day;
Total......... 37969
Irrigation.... 23056
Thermoelectric 6601
Public Supply. 6307
Aquaculture... 973
Industrial.... 400
Mining........ 272
Livestock..... 188
Self Supply... 172
Growing plants under glass and recycling water in these facilities radically reduces water demand for irrigation to about 20% conventional levels. So, that is reduced to 4.6 billion gallons per day when instituted. Furthermore, waste water has nutrients in it that are suitable for plants, once disease vectors are eliminated.
So, a near term program would entail;
(1) Conversion of agriculture to greenhouses
(2) Reuse of waste water as irrigation for green houses,
(3) Reuse desalted cooling water from power plants for public supply.
(4) Use of waste heat in power plants for desalination to increase supply.
(5) Use of desalted water for thermoelectric cooling.
In this way 38 billion gallons per day is reduced to 2.1 billion gallons per day, providing a 33.9 billion gallon per day surplus.
The USDA reports 7.9 million acres in California is irrigated.
It costs about $1 million per acre to put irrigated land under a glass greenhouse. It costs $400,000 per acre to put land under a plastic film greenhouse. Recovery of evaporated water in a greenhouse reduces water consumption by 80%. Another $500,000 per acre installs improved water management systems.
Even with the high priced spread this is $11.9 billion to cover this acreage. It saves 18.4 billion gallons per day in irrigation water - and by reuse of waste water from public sewage - use is reduced to zero.
The reduced water handling - which is energy intensive normally - is reduced.
Surplus energy is redirected toward air handling and temperature control - which changes energy impact by reducing energy needs, and increasing yields. Furthermore, the spread of pollutants is reduced the need for fertilizer is reduced, and the recycling of waste radically reduces adverse environmental impact. Finally, control of insects and reduced biohazards, mean less sales of insecticide.
The $8.70 per 1,000 gallons can be allocated to the different users to pay for the system. Power plants, Public users, Farmers, Industry, each pays $2.00 per 1000 gallons - and each gets a benefit in addition to water. Farmers for example, get greenhouse and improved water management.
Rebuilding our Energy Supply
While we're in the process of changing over the cooling system in our power plants and farms to reduce water consumption, why not add a secondary source of clean steam to reduce our energy dependence and cost?
If we wished to fee ourselves from coal, oil, natural gas and nuclear power we could do so, using advanced hydrogen producing solar panels as described here;
Creating Additional Sources of Water
Beyond this conventional approach, it is possible to harvest water from air, according to MIT scientists;
https://www.youtube.com/watch?v=h8vlzZ25vtg
A square meter of mesh produces 3 gallons per day in California along the coast according to UC Davis USGS and Berkeley Lab study done in 2014.
Whether you love fog,
Or hate it,
https://www.youtube.com/watch?v=wU6SKV1l7fw
A mesh arc over a free way, 40 meters in diameter and 20 meters tall eliminates intense fog conditions like that above inside the arc while collecting 300,000 gallons per day. To collect 6.8 billion gallons of water requires 22,670 miles of sea coast highways to be covered with water collecting mesh and channels. The rain water run off would also be captured nearly doubling the amount collected. Lighting and road maintenance of affected roadways would be improved, and advertising could be sold along the roadway to defray costs.
https://www.youtube.com/watch?v=Vrxyr1CjiSM
Solar panels equipped with mesh collect fog as well as rain.
California uses 38 billion gallons of water per day.
Half the power plants use a once through set up to cool power plants.
6.4 billion gallons per day is used by open loop once through cooling on 40 billion watts of generator capacity. Using closed loop cooling reduces this to 0.04 billion gallons per day for the capacity indicated. The capital cost of this is $8 billion.
20.2 billion gallons per day is used to irrigate 10.6 million acres of crops and none of this is recovered or recycled.
Covering the crops with low-cost greenhouses and recovering and recycling the waste water, reduces usage to 4 billion gallons per day whilst improving yields. The cost less than $12 billion.
These two programs taken together reduce daily usage from 38 billion to 14 billion gallons per day at a cost of $20 billion.
Taken together these measures alone basically ends the shortage.
Who pays?
The California Public Employees Retirement System - has over $300 billion in assets to invest. CalPERS pays $20.2 billion in retirement and health benefits and received $16.6 billion in contributions.
Thus the asset base must earn $3.6 billion or 1.2% positive return on average.
Providing a 3.6% annual return on investment to PERS for the $20 billion invested costs $720 million per year, or $2 million per day.
Dividing this across the 14 billion gallons of avoided water use $1 per 7,000 gallons. ($46.55 per acre foot!)
Current prices for water are $1,100 per acre foot, and were only $140 per acre foot 20 years ago!
1 acre foot is 325,851 gallons
California uses 38 billion gallons of water per day. Obtaining this water from sea water using multi-stage flash evaporators requires 23.3 billion watts of thermal energy. This may be met with 5.187 million tons of hydrogen gas each year, made from 0.4 billion gallons of desalted water each day.
Solar Hydrogen
Beyond retooling existing power plants, beyond reinventing California agriculture, beyond creating advanced systems of water collection from air, California can deploy new sources of fuel. That fuel is hydrogen.
Hydrogen may be used to displace other fuels as well.
https://www.eia.gov/state/?sid=CA
Replacing older forms of energy with solar hydrogen we obtain the following;
T=trillions,
B=billions,
M=millions.
Source....... T btu B MJ M tons H2 per year
Desalination. 5.187 - - - (waste heat)
Coal......... 43.8 46.2 0.326
Natural Gas.. 2456.4 2591.5 18.276
Gasoline..... 1617.2 1706.1 12.032
Fuel Oil..... 518.6 547.1 3.858
Jet Fuel..... 535.7 565.1 3.986
LPG.......... 57.3 60.4 0.426
Residual Fuel 167.1 176.3 1.243
Petroleum.... 313.2 330.4 2.330
Nuclear...... 193.9 204.6 3.699
Hydro........ 255.4 269.4 - - - (not needed)
Interstate... 828.5 874.1 15.805
............. ...... TOTAL.. 67.169
Producing 67,169,000 tons of hydrogen per year translates to producing 183,900 metric tons of hydrogen per day from 0.4 billion gallons per day of desalted sea water. Doing this with sunlight replaces all fossil and nuclear fuels, along with the purchase of all interstate electricity with hydrogen fuel used in the same thermal engine, in addition to building a hydrogen powered desalination plant network that produces 38 billion gallons of water per day.
https://www.wholesalesolar.com/solar-information/sun-hours-us-map
Hydrogen producing solar panels operating at 700 Watts/sq meter illuminated for 5 hours per day produces 88.8 grams/m2/day of hydrogen. Thus, 2,070 sq km of solar panels is sufficient to meet ALL the energy needs and ALL the water needs of the State of California by desalting sea water producing 1.41 trillion watts at peak output. The cost of this system is $70 billion.
https://www.futurity.org/full-spectrum-boosts-solar-cell-power/
https://www.google.com/patents/US20050051205
The cool part is this, namely, that by arranging to purchase hydrogen from me at 20% discount to market prices at the time the hydrogen is delivered, I can arrange financing of the equipment with an order for power, and provide 38 billion gallons per day of fresh water made from sea water free of charge!
In addition to converting all the coal fired, nuclear fired, and gas fired plants to hydrogen gas, in the process we'll convert the single pass cooling to a recycling cooling system, that radically reduces water demand while at the same time making use of the heat energy to run a desalination plant where practicable, to provide at least 38 billion gallons of water per day.