On November 2, 2016, BERC held its annual 2016 Resources Roundtable, featuring the Water-Energy Nexus. Attracting over 100 UC Berkeley students, faculty, and professionals, the conversations shed light on current and anticipated challenges to the water-energy nexus, as well as steps towards achieving a sustainable future in a world with growing population and resource demands.
The event featured a cross-disciplinary set of speakers from academia and industry, including Dr. Peter Gleick, co-founder of the Pacific Institute, and David Sedlak, UC Berkeley Malozemoff Professor and author of Water 4.0: The Past, Present and Future of the World’s Most Vital Resource.
I would like to share a few of the themes and takeaways from the day.
Impacts of Climate Change
- Water is how we feel climate change.
- When considering all resource, we must choose water and sacrifice other things. In our decision, we will likely use more energy to produce water to satisfy our needs.
- The effects of climate change are already being seen in California, through:
- Heat – more extreme hot days, fewer cold nights, and shifts in the water and growing cycles; more heat waves will stress demand for water and energy, and reduce the amount of electricity the power lines can hold while AC demand is at its highest.
- Air quality – increasing the potential for high ozone days, with increased heat comes increases in non-attainment ozone concentrations.
- Increased wild-fire risk
- Sea-level rise and associated sea-water intrusion into underground aquifers – Sea levels have risen by six inches or more along much of the California coast over the last century, increasing erosion and pressure on the State’s infrastructure, water supplies, and natural resources. Possible permanent inundation of wetlands, bays, low-lying delta areas.
- Increased flooding/storm surge risk in the Sac/San Joaquin delta and central valley
- Flooding/stormwater surge of critical infrastructure – roads and highways, ports, harbors, airports, wastewater treatment facilities, and power plants are located in low-lying coastal areas.
- Increased storm frequency and severity – affecting above ground power lines, and coastal powerplants are subject to storm surges. There is inundation of water into plumbed sewer systems where stormwater is combined with sewage.
- Water supply – increased temperatures, decreased snowfall, earlier snowmelt, and greater spring run-off means less water supply for everyone.
Infrastructure
- Consider the decomposition of water use: clean tape water vs recycled water for lawns and toilet flashes. There are high costs to build distributive systems, but once the systems are built, ongoing costs will be lower.
- Current water supply is built on snowfall. The current shift from snow to rain will change the entire distribution system.
- Costs of water supply = costs of carrying infrastructure.
- The cost of the energy input to treating and re-purposing wastewater is largely an economics problem. Water is the more constrained resource. Every day, we get sun from the sky that’s moving excess electrons off solar panels onto our lines, but we only get water from the sky a small fraction of the year – and then we have to figure out how to store it for the remainder. What we really have is a water storage problem in California.
- For electricity production, there is insufficient water in reservoirs and other hydro facilities for on-peak energy production during our long, hot, dry summers.
- Increased risk of fire is affecting electric transmission lines, caused by dry trees and other drought-stricken vegetation close to electricity transmission lines. This can take down large transmission lines, such as the north south connector, and cause more blackouts.
Water Tracking
- There is not as much data available about water usage as compared to energy usage.
- Smart sensors will provide information about how water is used (for showers, lawn watering, dish washing, laundry, etc.); it is currently in pilot testing.
Policies
- There is no central body that regulates water usage in California, only local utilities.
- To create the necessary drive for innovation, legislative and regulative changes are required.
- Water and energy can be viewed as two siblings (but not twins) of one parent. Water is the youngest sibling, and there is a lot about water conservation practices that can be learned from energy conservation.
- Water is considered a “civil right” so its price cannot be manipulated. It is hard to create conservation stimulus without price incentives.
- How do we make water sexy? We need to translate the problems to politicians and make the public excited about water conservation.
- There is a need for better forest management practices to prevent mud and other organic pollution from affecting the reservoirs and water supplies.
- Seek to increase utilization of stormwater capture and other potable and non-potable water reuse.
- We need to change what we consider as normal for landscape irrigation in urban and suburban environments; embrace low water plants and grasses, native plants, and climate appropriate landscaping.
- Careful consideration of placement and scale of any future water desalination facilities.We don’t want to be stuck with stranded assets where the plant has to run just to produce enough units of water to generate income to pay back the loans needed to build the plant.
- We need to pay attention to the quality of the wastewater used in energy production, particularly in fracking so that freshwater supplies are not contaminated.
Conclusion
- The soft path to water (incentives on demand side) can reduce water usage in California by 30-35% per capita. This is a short-term solution.
- We have 2-3 decades to determine a long-term solution to address anticipated population increases. A long-term solution could embrace use of hybrid systems (waste water for toilet & lawn and drinking tap water) and off-grid technologies, which can reduce water usage by 40-50%.