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RENEWABLE POWER VS THE ESTABLISHMENT (How water and sewer utilities play a part)

September 24, 2013
Climate, economy, engineering, Environment, finance, hydroelectric power, infrastructure, innovation, power demands, power-water nexus, renewable power, solar power, Uncategorized, water sewer management, wind power
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In June, President Obama made a speech about the increase in renewable power that the United States had created in the last 4 years, and announced goals to double this amount in the next four.  Virtually all of this power was solar and wind power.  Little mention was made of hydroelectric or onsite sources.  But the latter have been around much longer than the former sources and there may be options to increase their contributions under the right circumstances. 

 

Hydroelectric power has been in use in the US for over 100 years.  By the 1930s, 40 percent of the nation’s power came from hydroelectric dams, including some fantastic accomplishments of the time like the Hoover Dam.  Today we have over 100,000 dams in the US, most of which provide power.  Today hydroelectric is only 6 percent of our total.   The reluctance to continue with hydroelectric power involved fisheries, land acquisition costs and legal issues.  Some hydropower options are excellent.  Hurting fisheries (which disrupt local economies dependent on those fisheries) may not be, and therein lies part of the dilemma.

 

But water and wastewater utilities are actively looking for means to reduce power costs.  Depending on the utility, pumping water can account for 80-90 percent of total power consumption, especially with high service pumps on water systems that require high pressures.  More efficient pumps is one obvious answer, but of fairly limited use unless your pumps are really old.  Variable speed drives can increase efficiency, and the cost is dropping.  But note that with all that high pressure, how do utilities recapture the energy?  We often don’t and the question is whether there is a means to do so that can benefit up.  The first step is looking at plant hydraulics.  Is there a way to recapture energy in the form a pressure.  For example of reverse osmosis systems, we can install a turbine to recapture the pressure on the concentrate side.  They are not very efficient at present, but the potential is there.  On long gravity pipe runs for water supply, a means to recapture pressure might also be available. 

 

Of course on-site generation of power is a potential solution. Water and sewer utilities have land, and on the wastewater side, methane, so producing power is possible.  This solution, however, may not be embraced by power utilities due to the potential revenue reduction potential and loss of embedded reserve capacity at water and wastewater plants.  As the water facility takes on on-site generation, their load profile may shift significantly placing them in under a different rate structure. This may greatly reduce the benefit to the facility.  There are, however, approaches to permit win-win solutions. The goal is to put willing power and water utilities together to permit local generation that will benefit both power and water utility systems to encourage public – private partnerships.  A medium to large wastewater plant can generate at least a third of its power needs.  Some even more if they take in grease, oils and other substances that should not be put into the sewer system.  The potential there is significant.  EBMUD has a plant that is a net seller of power.  We should look for opportunities.  But don’t forget, water utilities can create hydropower without impacting fish populations. We just need to seek out the right opportunities.

OnSIte Power At Utility Plants?

March 6, 2013
Climate, Leadership, planning, power demands, power-water nexus, sustainability, Uncategorized
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Since Richard Nixon was President, the federal government has been talking about reducing our reliance of foreign oil.  Since 2008, our dependence has dropped from 57 to 42 percent.  The foreign oil has been replaced by domestic oil and gas, conversion of power plants to natural gas, and investments in renewable power like wind (4% US production and) and solar power.  Coal has remained a constant, although future regulations of coal plant emission may alter this.  Federal loans from DOE have included $13 billion for solar energy, 1.7 billion for wind and 10 billion for nuclear power.  All other renewables account for 1.2 billion.  Power companies have invested in the renewable technologies in part because of low loan rates from the federal government, and partly due to tax credits (2.2 cents/kW-hr), but power entities like NextEra Energy have made cleaner power a basis of their future.  So what does this have to do with water utilities?  First, water and wastewater plant are often the largest users on the power grind in communities.  This is why they are able to get load control agreements.  The peak demands are the load control agreements, which means power providers can construct fewer plants, and keep rates down.  At the same time water and wastewater utilities benefit fro reduced rates, but have construct backup systems (which are needed if the power grid fails anyway.  Benefit to both parties.  But as the demands for power on the grid increase, and as regional demands in areas that are substantially constructed already, locating new power is difficult.  Transmission losses are 6 or more percent, and involve complicated federal FERC regulations.  So the SMART grid issue is distributed power, and finding sites for distributed power might be tough.  Or maybe not.  Water and wastewater plants have land, so there is an obvious fit.  But the rub is that if the water and wastewater people own the facilities, it decreases the peak capacity, meaning the power entities must build more capacity.  So perhaps there is a means to get revenues (leases) to water folks, while helping the smart grid.  I am thinking about developing a project proposal for this.  Let me know if you are interested.  Meanwhile if you have a success story, I’d love to hear it.

Optimizing Water Supplies in the Face of Climate, Economic and Population Demands

February 26, 2013
Climate, Environment, infrastructure, Leadership, management, power demands, power-water nexus, sustainability, Uncategorized, water supplies
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The world population is expected to grow to over 9 billion by 2050, an exponential trend that has continued for several hundred years and see no end it site.  Megaregions as people flock to cities and industry will be commonplace.  The question is how will water supplies be impacted, or impact this trend.  Interestingly it varies everywhere.  For example, China and India are not expected to reap major benefits from climate changes, so their economies will grow as will populations.  They continue to construct coal fired power plants, and impact carbon dioxide and pollution levels, which does not help the climate issues.   Recall that Beijing was basically shut down for several days recent due to smog – seems like I recall the first air pollution regulations stemming from Henry the VIII decision to move the coal plants out of London during his reign 500 years ago because of pollution, but perhaps we need to relearn history J.  Of course China and India are expected to be less affected than the more historically developed countries in the northern latitudes that have been moving to renewable and less impactful power solutions with good reason.  Aside from these two economies, the rest of the northern latitudes are likely to see changes in temperature, variation in precipitation patterns and drought frequency changes.  That has major impacts for a billion people who will see water supply shortages occur much more often, and create a whole host of “winners” and “losers” in the water supply category.  Conflicts may result from the need to change increase water supplies as desperation kicks in.  Lawrence Smith, in his book 2050, suggests that while the far northern countries, the US, Russia, the Scandanavian countries, and Canada may see more land for agriculture and more water (at least in some areas), those warmer countries in the sub-Sahara, will become more desperate and dangerous to the world order.  Water will be the new oil, and the tipping point for sustainability, akin to peak oil, needs to be developed.  The cost will be significant, but the failure will be catastrophic to global economies.  This is part of why the global pursuit of renewable power, local solutions and green jobs.  It is why the definition of sustainable water supplies continues to evolve as we understand that the impacts, or the constraints of water supplies is far more reaching than most engineers and planners have traditionally dealt with.  AWWA published a Sustainable Water CD several years ago.  It was a series of papers of different aspects of sustainability as applied to water resources.  The last paper summarized the findings and compared it to the initial paper discussion.  The conclusion was the concept is evolving.  Climate, power, agriculture, natural systems, local economies, local economic contributions to regional and national economies and politics all impact pure science recommendations for water supply allocation.  The question is can we overcome the politics to create a optimized science solution to sustain water supplies and economies.  An old Native American proverb comes to mind:  We do not inherit the Earth from our grandparents, we borrow it from our grandchildren.

Leadership with Water-Energy Nexus?

January 26, 2013
Climate, communciations, Environment, finance, groundwater, infiltration, infrastructure, Leadership, management, power demands, power-water nexus, sanitary sewer, sustainability, water sewer management, water supplies
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In our prior blog discussions the theme has been leadership.  Vision is needed from leaders.  In the water industry that vision has to do with sustainability in light of competing interests for water supplies, completion for funds, maintaining infrastructure and communicating the importance of water to customers.  The need to fully to optimize management of water resources has been identified.  The argument goes like this.  Changes to the terrestrial surface decrease available recharge to groundwater and increase runoff.  Urbanization increases runoff due to imperviousness from buildings, parking lots, and roads and highways that replace forest or grassland cover, leading to runoff at a faster rate (flooding) and the inability to capture the water as easily.  In rural areas, increased evapotranspiration (ET) is observed in areas with large-scale irrigation, which lowers runoff and alters regional precipitation patterns. At the same time there are four competing sectors for water:  agriculture (40% in the US), power (39% in the US), urban uses (12.7%) and other.  Note the ecosystem is not considered.

New water supplies often have lesser quality than existing supplies, simply because users try to pick the best water that minimizes treatment requirements. But where water supplies and/or water quality is limited, energy demands rise, often to treat that water as well as serve new customers. For many non-industrial communities, the local water and wastewater treatment facilities are among the largest power users in a community.  Confounding the situation is trying to site communities where there is not water because the power industry needs water and the residents will need water.  It is a viscous cycle.  When you have limited water supplies, that means your development should be limited.  Your population and commercial growth cannot exceed the carrying capacity of the water supply, or eventually, you will run out.  Drawing water from more distant place can work for a time, but what is the long-term impact.  Remember the Colorado River no longer meets the ocean.  Likewise the Rio Grande is a trickle when it hits the Gulf of Mexico  As engineers, we can be pretty creative in coming up with ways to transfer water, but few ask if it is a good idea.

Likewise we can come up with solutions to treat water that otherwise could not be drunk, but, that may not always be the best of ideas. Adding to the challenge is that planning by drinking water, wastewater, and electric utilities occurs separately and is not integrated. Both sectors need to manage supplies for changes in demands throughout the year, but because they are planned for and managed separately, their production and use are often at the expense of the natural environment.  Conflicts will inevitably occur because separate planning occurs (for a multitude of reasons, including tradition, regulatory limitations, ease, location, limited organizational resources, governance structure, and mandated requirements). However, as demands for limited water resources continue to grow in places that are water limited, and as pressures on financial resources increase, there are benefits and synergies that can be realized from integrated planning for both water and electric utilities and for their respective stakeholders and communities. The link between energy and water is important – water efficiency can provide a large savings for consumers and the utility.   As a result, there is a need to move toward long-term, integrated processes, in which these resources are recognized as all being interconnected .  Only then can the challenges to fully to optimize management of water resources for all purposes be identified.

Anybody have any good examples out there?

Energy Leadership in the Water Industry

January 23, 2013
Climate, Environment, groundwater, infrastructure, Leadership, management, planning, power demands, power-water nexus, sustainability
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Water and energy systems constitute the foundation for modern civilization around the world.  Without water, societies never get started, and without power, it is difficult for economies to grow.  At the same time, modern power generating equipment needs water for cooling and processes, creating an interdependency between water and energy infrastructure and potential for conflict over water resources. As a result, the Energy-Water Nexus is a topic of great interest and discussion among federal policy-making and regulatory entities; private and public sector water and electric utilities; state and local governments, and many supporting technical, educational, professional associations. At the nexus of water and energy exists a host of societal issues, policy and regulatory debates, environmental concerns (local and global), technological challenges, and economic impacts that must be balanced or optimized to permit ongoing economic development for all (NETL, 2008).

Estimates indicate that from 1950 to 1980, demands for water increased steadily across all sectors, with 1980 being the peak water use year.  However, since 1980, withdrawals declined.  Despite the overall decline, the built environment demands continued increase. This of course ignore the natural environment demands, which may play a large part in the economic stability of some regions.  Unlike water demands, the total US power consumption continues to climb as a result of population increases.  The US Census Bureau (2004) projects that the national population will increase from 282 million people in 2000 to 420 million by 2050.  The Energy Information Administration (EIA) project, assuming the latest Census Bureau projections in its reference case, the U.S. population to grow by about 70 million in the next 25 years and electricity demand to grow by approximately 50 percent (EIA, 2006). More people, means more power.  More power means more water for cooling unless all new power is solar or wind, something highly unlikely.  On the current track, which suggests and expansion of fossil fuel plants, the power sector may be highly vulnerable to changes in water resources, especially those that are already occurring, and are likely to intensify, as result of climatic changes (Vorosmarty et al 2000, Bates et al 2008, Dai 2010, NETL 2010d).

Adding to the challenge is that planning by drinking water, wastewater, and electric utilities occurs separately and is not integrated. In the US, the energy sector uses 39% of the water withdrawals on an annual basis for cooling, immediately behind the 40% used by agriculture (Lisk et al, 2012; GAO, 2012).  Urban demands (12.6% of water use – Sanders and Webber, 2012) require clean water supplies to protect public health.  Both sectors need to manage supplies for changes in demands throughout the year, but because they are planned for and managed separately, their production and use are often at the expense of the environment (NREL, 2011). This separate planning occurs for a multitude of reasons, including tradition, regulatory limitations, ease, location, limited organizational resources, governance structure, and mandated requirements. However, as demands for limited water resources continue to grow among all sectors, and as pressures on financial resources increase, there are benefits and synergies that can be realized from integrated planning for both water and electric utilities and for their respective stakeholders and communities. The link between energy and water is important – water efficiency can provide a large savings for consumers and the utility.  Reduced energy consumptions benefits the consumer – but should always be considered as one of the first steps (Gould, 2011).  As a result, there is a need to move toward long-term, integrated processes, in which these resources are recognized as all being interconnected (NREL, 2011).  Only then can the challenges to fully to optimize management of water resources for all purposes be identified (Scanlon et al 2005).

The lack of planning creates the situation where competition for water between agriculture, power and urban uses will reach a tipping point (or beyond in many basins) as an expected increase in thermoelectric capacity by electric utilities, and an increasing prevalence of droughts could induce possible water shortages.  By 2025, Ciferno (2009) suggests the most vulnerable areas for water shortages are fast growing areas:  Charlotte, NC, Chicago, IL, Queens, NY, Atlanta, GA, Dallas, TX; Houston, TX, San Antonio, TX, and San Francisco.  Immediately behind these areas are Denver, CO; Las Vegas, NV; St Paul MN, and Portland OR (Ciferno,2009). Hightower (2009) notes that virtually all the states west of the Mississippi and many southeastern states will experience regional or statewide water shortages in the coming decade (2010-2020).  The South and the Southwest are particularly vulnerable (Glassman, et al, 2011) because they rely on air conditioning to provide a comfortable environment, which requires more power for a growing population, requiring more water for cooling power plants.

These projections come with recent experience that is likely to foretell the future.  The south, Texas and parts of the west have had repeated drought periods in recent history.  During the summer and fall of 2007, a serious drought affected the southeastern United States.  River flows decreased, and water levels in lakes and reservoirs dropped. In some cases, water levels were so low that power production at some power plants had to be stopped or reduced (Kimmel and Veil, 2009). The Tennessee Valley Authority (TVA) Gallatin Fossil Plant is not permitted to discharge water used for cooling back into the Cumberland River due to thermal pollution (water > 90 F) (WSMV Nashville 2007; Kimmel and Veil, 2009; NETL 2009c).  Nuclear and coal-fired plants within the TVA system were forced to shut down some reactors (e.g., the Browns Ferry facility in August 2007) and curtail operations at others. This problem has not been limited to the 2007 drought in the southeastern United States. A similar situation occurred in August 2006 along the Mississippi River (Exelon Quad Cities Illinois plant).  Other plants in Illinois and some in Minnesota were also affected (Union of Concerned Scientists 2007). The production of gas from oil shale and biofuels has exacerbated the issues in the Plains states (Kansas, Oklahoma, Texas), Upper Rocky Mountains, and the Ohio River Valley (Hightower, 2009; Kimmel and Veil, 2009).  DOE (2006) specifically identifies where new power plants have been opposed because of potential negative impacts on water supplies (Tucson Citizen, 2002; Reno-Gazette Journal, 2005; U.S. Water News Online, 2002 and 2003; Curlee, 2003). Recent droughts and emerging limitations of water resources have many states, including Texas, South Dakota, Wisconsin, and Tennessee, scrambling to develop water use priorities for different water use sectors (Clean Air Task Force, 2004a; Milwaukee Journal Sentinel, 2005; GAO, 2003; Curlee, 2003; Hoffman, 2004; U.S. Water News Online, 2003)

So what is currently happening?  Current legislation  is mostly silent on the power-water nexus.  This is not to say that little is being done. A number of federal agencies are actively involved with the power-water nexus, including DOE, via NETL, and NREL, NOAA, USEPA via water Wise and Energy Star, BLM though management of land and water resources in the west, USDA and Department of the Interior/USGS which inventories water supplies.  However, DOE (2006) noted that collaboration on energy and water resource planning is needed among federal, regional, and state agencies as well as with industry and other stakeholders.  GAO (2012a) notes that the growth in water and energy demands is occurring at a time when the nation’s supplies are stressed by a growing population, a variety of new and changing uses, and environmental challenges such as climate change, but none of the involved agencies consistently or strategically collaborate on to ensure a harmonized approach to energy and water resource planning.

Effective integrated energy and water policy planning will require identifying the individual and cumulative impacts that power plants have on water resources and the vulnerabilities of specific power plants to changes in water resources (Wilkinson 2007, Scott and Pasqualetti 2010;Stillwell et al 2011; Kenney and Wilkinson 2012). From a systems perspective, a sustainable society is one that has in place the institutional, social and informational mechanisms to keep in check the feedback loops that cause exponential population growth and natural capital depletion.  A sustainable world is not a rigid one, where population or productivity is held constant.  Yet sustainability does require rules, laws and social constraints that are recognized and adhered to by all (Meadows, 2005).   Integrated planning implies removing silos, working collaboratively, and using resources wisely. It implies using the combined intelligence of multiple parties in the planning and fulfillment of goals. It implies linking a vision, priorities, people, and institutions into a flexible system of evaluation and decision-making.  In other words, leadership.

Details on refrences available