Smart Ideas in Energy and Water from the Southwest US: Technologies that improve energy and water management and their economic benefits
By: Erum Azeez Khan
The recent revealing of President Obama’s Climate Action Plan echoes the goals of the European Union’s energy policy to create a low-carbon economy. In efforts to reduce fossil fuel dependence and add more renewables in the energy mix, the role of water is often left aside. Water and energy are interlinked and it’s important to understand how the two influence each other. During an ELEEP study tour in to the US Southwest, we did just that. Desert-like states such as Nevada and Arizona are no strangers to high temperatures and drought-like conditions, yet they have bustling cities with bright lights and ample water supply.
As we traversed the Southwest, we met with government agencies, private companies, research laboratories, and a variety of special interest groups, discussing the complex relationship between energy production and water consumption. We saw how problems transformed into solutions, or better yet opportunities to reduce environmental stress and increase profits. A glimpse into the water-energy nexus reveals how public and private industries are uniquely positioned to shape the sustainable, economically competitive use of natural resources and demonstrate effective evidence-based policy making.
Here are some of the technologies that play a central role in the water-energy debate and how their applications influence local and national policy.
Cooling Power Plants with Water
Power plants are the most water-intensive technologies in developed nations. In fact, the United States uses up to 40% of freshwater withdrawals to cool power plants and Europe uses about 43% of their water for the same purpose. Although there is a difference between withdrawal and consumption, where consumption is the removal of water from the system (such as household and agriculture use) and withdrawal is the temporary use of water that is eventually returned to the water source. In this case, it’s the volume and intensity at which the water is being used that is of utmost concern.
Of the different types of power plant cooling systems, once-through gets the most red flags as it is the most water-intensive followed by recirculating, pond, hybrid, and then dry-cooling systems. Although once-through has unfavorable high water withdrawals, it’s the return of hot water into the natural water system that places environmental stress on aquatic life. Because of this and the large volume of withdrawal, the EPA has proposed standards for cooling water systems under the Clean Water Act and suggests that inefficient power plants take steps in retrofitting existing plants with less water intensive cooling systems. However, this would come with exorbitant capital costs and revenue loss due to extended outages needed to change the system according to the Electric Power Research Institute. Building entirely new plants with water efficient cooling systems, and shutting down old ones may be the most economical way forward.
When it comes to building power plants, it’s all about location, location, location. Over at Sandia National Laboratories in New Mexico, researchers are exploring water consumption patterns of power plants around the western region. Their research resulted in a geographical model of strained and available water resources to aid in siting for power plant construction and projected water availability in the coming years to see which cooling system would be the most appropriate.
By understanding what locations and systems are the most efficient for building power plants, policies can be drafted to ensure energy producers take the most environmental, yet profitable choices.
Using Produced Water for Biofuels
Another means to tame the water-energy giant is take a look at the copious amounts of water being used to extract oil and gas from the ground by either traditional means or hydraulic fracturing. After this water is used, it is considered industrial waste or “produced water” which is rich hydrocarbons, metals, and organic compounds. This water would need to undergo multiple rounds of treatment before being suitable for human use.
But what is waste? Is it something you no longer have use for? Can we use science and technology to find novel uses for various form of “waste”? These questions are being asked by the folks at Los Alamos National Laboratory (LANL). They have figure out a process to grow algae with produced water, which can later be converted into biofuels. This research is being conducted by Jeri Sullivan, a technical staff member at LANL , where they are using untreated produced water from oil wells in Jal, New Mexico for algal production. An innovative part of the work is the use of a membrane bioreactor that is normally used for freshwater sewage treatment, but now it is successfully adapted for produced water and algae. The team at LANL has calculated a 44% cost savings in using produced water rather than freshwater in production of this biofuel. This is a leap forward in biofuel research and may benefit the EU’s goal of using biofuels as 10% of their fuel economy by 2020.
This is only example produced water can be used, surely there are others. The central idea here is to reconsider the concept of waste to be something of value when used in new ways.
Carbon Sequestration for Water Extraction
Carbon capture and storage is the talk of the town, yet commercial viability is yet to be seen. Again, researchers at LANL have developed a process and cost model for the use sequestered carbon to extract water from the ground, a step in a different direction from the fully funded Enhanced Oil Recovery (EOR) for which sequestered carbon was initially intended. Here, the carbon injected into the ground would be used to displace or extract water in order to control the CO2 placement in the subsurface. If the water can be treated for human consumption economically, then this creates a new water resource. The model created by LANL evaluates basic water quality, flow rates, volume, and treatments with costs ranges to determine which methods are the most useable.
However, the financial costs, energy requirements, and risk of leakages are all major challenges to be considered when going down this path. More in-depth simulations, modeling and safety measures need to be put in place to avoid any environmental and economic damages.
Genetic Selection for Changing Climates
At The Arboretum at Flagstaff in Arizona, research is being carried out by Northern Arizona University (NAU) on the ecological and evolutionary effects of climate change, specifically how genetics will select for characteristics that cater to the climate changed environment.
Tom Whitman, who is leading the team of NAU researchers proposes that drought can cause plants to use water more efficiently and cause more O2 production due to higher levels of CO2 in the air. “Species will evolve to tolerate and adapt to climate change,” says Whitman, “a slight change in temperature can cause huge changes in ecosystems.” He also suggests using climate modeling to predict the climate conditions as little as 2 years ahead in an effort to relocate plants to new terrain where they would be more suited. This could be an action-oriented step forward.
Whitman further discussed genetic fingerprinting or genotyping various species of plants in order to select genes that are responsible for reduced water intake and increased oxygen production. Plants with these features will have two-fold benefits by using less water and can certainly play a role in carbon offset-projects.
Additionally, the researchers at The Arboretum discussed other “garden technologies” like moisture sensors and smart irrigation systems that provide an accurate amount of water to plants that significantly cuts down water loss and cost. The trick here is to identify the lowest possible cost to manufacture the garden gadgetries in order to get in the hands of farmers in order to reap the most rewards. Slowly but surely, hopefully.
Closing the Loop with Desalination
Using a desalination plant to clean water is not a new technology, but incorporating it into the waste water cycle of manufacturing plants is. The Intel campus in Arizona has invested $5 billion to add a reverse osmosis desalination plant to its manufacturing capacity which is run by city of Chandler in Arizona.
The Reverse Osmosis Facility uses a series of nanofiltration tubes that remove impurities from the wastewater on a molecular level. When the water reaches drinking-level standards, it then goes to recharge an aquifer through direct injection wells ready to be reclaimed by the community and company. Through this desalination facility and other water conservation techniques (like using the local community’s wastewater to cool their energy systems), Intel has reduced its water consumption by half, from 8.9 million gallons/day (mgd) to 4.8 mgd.
Intel’s initiative in incorporating a desalination plant in its water lifecycle is an excellent example of corporate responsibility undertaken by large manufacturing plants, yet saving millions of dollars in energy and water conservation. And it is probably no surprise that this company is also known for being the largest purchaser of green technologies in the United States and ranks No. 1 on the EPA’s Green Power Partnership list. I would definitely recommend keeping an eye on this company to see what other tricks they pull from their sleeves.
Smart uses of new technology set the stage of how energy and water can work together in order to manage natural resources and build a more responsible economy. There is no one solution that will beat out others, but a combination of solutions that can reduce water usage, environmental contamination and lower the carbon footprint of nations. It is important for policy makers and the private sector to coordinate R&D activities, prioritize energy and water policy on national and regional agendas, reinforce mechanisms that are proven solutions, and to build a platform for effortless technology transfer. It’s a balancing act, and policies geared to foster technological development and “environmental” entrepreneurship will aid in moving toward a low-carbon economy, so as long as there is the societal and political will to do so.