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Water Conservation (In Progress)
Updates on BIF Greywater Meter, Increase Cooling Tower COC, and Design Center Greywater Piping recommendations. Discussion on the development of water use dashboard.
Water and energy are intricately linked. The challenge of reducing campus GHG emissions should involve looking at the importance of water in at least two ways.
The first is to understand the significance of indirect GHG emissions associated with the use of treated water and the discharge of wastewater to the sanitary sewer. Another way to look at water in this context is as further incentive for improving energy efficiency. This section addresses both of these topics. In fiscal year 2009, campus used 1,202,497 kgal (1,000s of gallons) of water. In fiscal year 2008, campus used 1,312,492 kgal. In fiscal year 2007, campus used 1,262,491 kgal. The costs associated with these amounts of water use were $2,287,351 in fiscal year 2009, $1,762,819 in fiscal year 2008, and $1,661,137 in fiscal year 2007. Another 50 percent rate increase is expected in the next fiscal year.
Since the University of Illinois is a major water user, the baseline GHG emissions study should include an effort to determine the significance of indirect emissions due to water use. Significantly reducing campus water use will require greater understanding of how water is used on campus. Current water use categories include:
- Major Labs – 22 percent
- Chiller Plants – 19 percent
- Abbott Power Plant – 14 percent
- University Housing Facilities – 14 percent
- Irrigation – 7 percent
- Campus Recreation – 1 percent
- Other (Domestic Use - Classroom, office, etc.) – 23 percent.
The second major way to look at water in the context of reducing GHG emissions is to account for the fact that certain energy efficiency improvements reduce water use. In other words, the economic value of energy efficiency is often greater than just the economic value of the energy saved. For example, energy efficiency improvements that reduce cooling loads will save a proportional amount of cooling tower water. When cooling towers use less water, they require proportionately fewer chemicals, maintenance, etc. Therefore, a cooling efficiency improvement will result in savings in the cost of energy, the cost to purchase water, the cost to discharge water to the sanitary sewer, the cost of cooling tower chemicals, and the cost of cooling tower maintenance. Economic justification is easier when all of these cost savings are captured. The Illinois Sustainable Technology Center has performed true cost of water accounting for Ford and Caterpillar, and the results have shown that the actual cost to use water can be 5 to 20 times greater than the cost of the water alone. Campus has begun to utilize efficient water fixtures, including low-flow aerators for faucets, dual-flush and high efficiency toilets, high-performance low-flow showerheads, and pint urinals. These fixtures will continue to be utilized in new buildings and retrofits, and newer technologies to improve upon these efficiencies will be researched and harnessed. Non-potable sources of water will also be utilized when appropriate, including untreated raw water, sump pump discharge, cooling tower wastewater, stormwater, and graywater. The university has a raw water system across campus that has yet to be activated. This would allow campus to purchase lower cost, non-treated raw water from the water company. The Business Instructional Facility is already plumbed in a way that would allow for raw water to be used for toilet and urinal flushing when available. Campus will connect to the raw system and explore ways to use other non-potable sources in this system. A next step would be to conduct an analysis to account for the true cost to use water on campus.
Water Targets and Strategies
Targets1) Reduce potable water usage and its associated emissions from a fiscal year 2008 baseline:
a) 20 percent by 2015
b) 30 percent by 2020
c) 40 percent by 2025.
- Commission an internal, student-assisted study to determine a detailed water use baseline, the "true cost of water," and the related emissions.
- Include "true cost of water" charges with the energy billing program.
- Begin utilizing non-potable water, including untreated raw water, sump pump discharge, cooling wastewater, stormwater and graywater.
- Connect the raw water system by 2020.