|Water Energy Nexus|
How much energy can we save by conserving water in our homes and businesses?
And when we save energy, how much water are we keeping in our rivers and streams?
At the Coalition, we're illustrating the connections between water use and energy production in the basin, as part of our ongoing effort to significantly reduce carbon emissions, decrease energy costs, and improve water quantity and quality.
Most of us recognize how to save water-- by taking shorter showers, or cutting back on watering the lawn. And we can save energy by drying clothes outdoors, unplugging computers and TVs when not in use, and washing clothes on a "cold" setting.
But there's more to the story of energy and water. There is also the "indirect" energy cost in our water systems-- because it takes energy to bring water to our homes in the first place.
To illustrate-- consider how heavy water is. We all know how difficult it can be to carry a gallon of water up a flight of stairs. So imagine the energy it takes (and the greenhouse gases produced) to transport, treat, and heat water in our cities and towns. And, meanwhile, it also takes water to produce all this energy in the first place.
We hope the tools and calculators provided on this page will increase awareness of how conserving water can also reduce energy costs, all while lowering greenhouse gas emissions. And, we're outlining steps that citizens can take to cut down on water and energy use, saving money at the same time.
Water-Energy Nexus - The Facts:
- Energy production in the U.S. requires more water than any other sector.
- 48% of all water withdrawls in the U.S. are used for thermoelectric power production. 34% of all withdrawls are used for irrigation. From the USGS report, Estimated Use of Water in the United States (2000).
- For many communities, the energy required for supplying and treating water and wastewater constitues the largest municipal energy cost.
- The United States uses the equivalent of 520 billion kilowatt hours per year-- equivalent to 13% of the nation's total electricity use-- to pump, heat and treat water. This is equal to the output of over 150 typical coal-fired power plants.
- Approximately 56% of all water that made its way into public systems was delivered to domestic users, with commerical use ranking a distant second.
graphic courtesy Union of Concerned Scientists (UCS)
At the Coalition, we're working to localize the impacts of global climate change-- and of the water-energy nexus. We want to take a closer look at our energy production and water use in the basin, to see how water conservation can potentially lower energy costs, and how saving energy might also conserve water.
Showerhead Conversion Calculator: This calculator demonstrates the water, energy, and carbon costs associated with different types of showerheads. Showering is one of the most energy-intensive end-uses of water, and this calculator demonstrates how much water and energy can be saved when using a more efficient showerhead model. This is an excel-based calculator, with areas for users to plug in information. See the tabs at the bottom of the sheet for doing calculations based on either an Electric Water Heater or a Natural Gas Water Heater.
Low-Flow Toliet Energy Savings Calculator: This calculator illustrates the water, energy, and carbon costs of different toliet models. Because toliets use only cold water, this is a useful tool for users to understand the indirect cost of energy and greenhouse gas emissions in their water use. National averages are provided in this tool. However, the Coalition hopes to work with local water and wastewater utilities to determine the energy intensity of their water systems, and provide a more accurate picture of the energy and greenhouse gas emissions embedded in the water used for toilet flushing.
Community Water and Energy Savings Calculator: This calculator provides an estimate of the water, energy, money, and carbon saved by adopting indoor water efficiency improvements at a community level. This is an excellent tool for agencies or municipalities to use when attempting to create incentive based programs for water conservation. Users can select from five different indoor residential uses of water-- toliets, showerheads, dishwashers, clothes washers, and faucet aerators-- to assess relative savings of conservation progams.
Water Heating Calculator: The water heating calculator allows users to determine the energy and greenhouse gas emissions embedded in a gallon of water in a specific location. Users plug in their zip code and water heater temperature setting.
Thank you to River Network and Pacific Institute for allowing reproduction of water and energy calculators
Green Blocks: Interested in making water and energy efficiency improvements to your home? In 2008, Missoula initiated its Green Blocks program, which brings significant energy-saving home improvements to Missoula homeowners free of charge. Residents have the opportunity to join together as a neighborhood to apply for energy audits and free energy efficiency upgrades. For more information please visit the Green Blocks webpage.
Gray Water: Thanks to a host of conservation lobbyists, in 2007 the Montana Legislature legalized gray water reuse. Laws were then updated in 2009 to expand the use of gray water systems beyond single family home use. "Gray water" is defined as watewater that does not contain human waste-- water from sinks, dishwashers, washing machines, and showers. Through a re-use system, gray water can be recycled on-site and used in landscape irrigation. Learn more about gray water systems.
How you can make a difference in your watershed:
Balance your water footprint: In the Clark Fork watershed, our rivers and streams are working overtime to keep up with increasing demands on water consumption, especially in the face of population growth, energy production, and climate change. Find the water footprint for your home, business, or family, and then balance your water use through the purchase of Watershed Restoration Certificates (WRCs). Calculate your total water footprint and give back to the Clark Fork today.
Links and Resources:
Union of Concerned Scientists (UCS): The UCS "Water and Energy Collision" webpage explores the intersection of water use and energy production, and includes downloads and links to additional resources on climate change. Download the UCS brochure The Energy-Water Collision: 10 Things You Should Know
Cases in Water Conservation: This report, published by the EPA in 2002, uses examples from across the country to show how water conservation and efficiency can benefit utilities. You can make the case that these measures will work in your community.
eGrid Power Profiler: This epa.gov site offers analysis of electricity source production by zip code. Simply plug in your zip code and electric distribution company, and receive a breakdown of the electric power sources for your residence or business. The electricity required to power the Coalition's office in downtown Missoula comes from a mix of sources. The "Electricity Fuel Mix" for our office zip code comes from: 48.6% hydropower, 34.4% coal, 10.8% gas, 3.3% nuclear, 2.3% non-hydro renewables, and 0.3% oil. Want to find out the "fuel mix" at your home or business? Visit the Power Profiler at epa.gov.