Energy and Water Nexus Summit
Water 2- What are our options?
Prioritizing conservation, or prioritizing
supply increase- what are the potential
economic and environmental impacts?
Val S. Frenkel, Ph.D., P.E., D.WRE.
How Much Water We Have?
More than 70% of Earth surface covered by WATER, Radius of Earth = 6 378.1 kilometers
How Much Water We Have?
All the Water on Planet Earth
Illustration Credit & Copyright: Jack Cook, Woods Hole Oceanographic Institution, Howard Perlman, USGS
oceans of water cover about 70 percent of Earth's surface. The radius of water ball ~ 700 kilometers, less than half the radius of the Earth's Moon,
Water Cycle
Water Cycle
ENERGY
GENERATOR
Water Cycle
ENERGY
GENERATOR
Precipitations, Snowcaps
Ocean
Reuse
Water Flow As We Use It
Water Flow As We Use It
Conservation
Reuse
Desalination
What We considering When Need More Water:
•
•
•
•
•
Availability
Sustainability of supply for long term
Quality of source water and treatment which is required
Environmental aspects
Regulatory compliance when developing new source
and easiness to permit it
• And….
What We considering When Need More Water:
•
•
•
•
•
Availability
Sustainability of supply for long term
Quality of source water and treatment which is required
Environmental aspects
Regulatory compliance when developing new source
and easiness to permit it
• And COST
“…if we could ever competitively, at a
cheap rate, get fresh water from salt
water, that it would be in the long-range
interests of humanity which would really
dwarf any other scientific
accomplishments.”
- President John F. Kennedy
April 12, 1961
119 - The President's News Conference
Recycled water can be a new water resource
• Traditional potable supply
(surface and groundwater)
• Sea and brackish water
(surface and groundwater)
• Wastewater
• Rainwater capture
• Greywater
Desal
Recycled Water
Summary
When we need more water we are looking three key direction:
- Conservation
- Reuse
- Desalination
To be sustainable all 3 key directions should be explored. Cost of
water is one of the dominating factors when exploring additional
water source. For the long term sustainable water supply
desalination may be an important part diversifying water supply
portfolio.
Val S. Frenkel, PhD, PE, DWE
THANK YOU
Malcolm Pirnie / ARCADIS
(415) 412-1380
[email protected]
Back-Up Parked Slides
Typical recycled water quality objectives for
irrigation
Parameter
Sodium
Chloride
Bicarbonate
Copper
Zinc
Manganese
Iron
Boron
Fluoride
Aluminum
Electrical Conductivity
Adjusted Sodium Adsorption
Ratio/Salinity Ratio
Symbol
Na
Cl
HCO3
Cu
Zn
Mn
Fe
B
F
Al
ECW
RNa/ECW
Concentration
<100 mg/L
<175 mg/L
<250 mg/L
<0.50 mg/L
<1.0 mg/L
<0.20 mg/L
<1.0 mg/L
<0.70 mg/L
<4.0 mg/L
<3.0 mg/L
<1200 S/cm
<5.0
Recycled water can be added to Surface Spreading
(Recharge Ponds)
• Often blended with
surface water
• Can be used to
enhance or create
wetlands
• Recycled water
recharges
groundwater
Subsurface injection of recycled water
(Injection Wells)
• Provides a more direct
enhancement to
groundwater basin
• RW often blended with
other water sources
• Monitoring wells can be
used to check water
quality
Groundwater recharge typically requires
separation from neighboring drinking wells
Energy Consumption by Desalination
Desalination
Energy
Reverse Osmosis Desalination Process Schematic
90-95% of Entire Energy
Feed
Water
Structure
PreTreatment
Solids
Disposal
Reverse Osmosis
Energy
Recovery
Brine
Disposal
Water
Conditioning
Product
Water
Typical Breakdown of Desalination Cost, %
Seawater
Brackish water
Fixed costs
35 %
50 %
Energy
45 %
15 %
Labor
5%
10 %
Membrane s
replacement
5%
5%
Maintenance
7%
10 %
Consumables
3%
10 %
Questions?