Through the other WE credits, you’ve already realized water savings from landscaping (WEc1), wastewater processing (WEc2), and specific domestic water fixtures and fittings (WEp1 and WEc3).
This credit deals with the “rest” of the water—the process waterProcess water is used for industrial processes and building systems such as cooling towers, boilers, and chillers. It can also refer to water used in operational processes, such as dishwashing, clothes washing, and ice making.. It covers any fixtures, appliances, and processes that aren’t included in other credits or in the Energy Policy Act of 1992, and establishes maximum water use limits for clothes washers, dishwashers, ice machines, food steamers, and pre-rinse spray valves. In order to achieve this credit, you must demonstrate that you meet the thresholds for four of these five equipment types—or prove that your project reduces process water use by 20%.
No garbage disposals are allowed anywhere in a school earning this credit. You will also be required to use only boilerless steamers, and use no garbage disposals, no refrigeration equipment using once-through coolingA once-through (single pass) cooling system is one which water from any source is used to transfer heat from equipment or processes and then discharged. (including kitchen and mechanical equipment), and no water-cooled ice machines.
If your project doesn’t have a kitchen, it’s unlikely that you’ll be able to achieve the credit using the prescriptive path—four of the five eligible equipment types are kitchen appliances. You can still determine the baseline water use for other process-water equipment and calculate a 20% reduction in order to achieve the credit—but it can be more difficult to prove, mainly because it is challenging to establish an industry baseline.
Some project teams may be surprised to find that garbage disposals are not allowed under this credit. After all, there is a wide perception that garbage disposals offer environmental benefits by reducing landfill waste.
A standard commercial steamer consumes about 80,000 gallons per year—most of it tap water to cool the condensate. Shown here is a boilerless steamer that dramatically reduces water use. Photo – AccuTemp Products, Inc. The reality is that garbage disposals consume large quantities of potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. for conveying the food waste—especially relative to more traditional means of disposal, composting, or pulping. Processed food waste from garbage disposals also puts a significant burden on wastewater treatment facilities, where the increased load of nutrients and solids demand additional energy and chemicals for treatment.
Removing garbage disposals can be seen as a challenge for many schools, because it typically requires schools to find an alternative means to dispose of food waste. Schools that already have a system in place for composting food waste—rather than using garbage disposals—will probably find this credit easier to achieve.
Although it’s spelled out in the credit requirements, it’s easy to overlook these exclusions:
Garbage disposals consume large quantities of potable water. Collecting food waste for composting is ideal but food waste can be sent to the landfill if there is not a better alternative. Water efficient scrap collectors and pulpers may also be considered by GBCI.
The July 2010 LEED reference guide addenda states “‘At least 4 process items’ with ‘All appliances within at least 4 equipment types’" must be used. In other words, if you used just four compliant dishwashers, you would likely not achieve this credit.
The water use for each equipment type needs to be equal to or lower than the maximum water use specified in the credit language.
This credit addresses process-water use reduction only. Other WE credits address landscaping (WEc1), wastewater processing (WEc2), and specific domestic water fixtures and fittings (WEp1 and WEc3). Process water, like kitchen, laundry, and mechanical equipment, is what’s left for this credit.
Determine where your school uses most of its process water and examine the feasibility of purchasing appliances that meet the credit requirements for water use reduction.
This credit can be earned either through a performance-based approach, a prescriptive approach, or a combination of the two. The choice is up to the project team, but the prescriptive path may be easier as it requires no calculations.
Garbage disposals are not allowed in projects pursuing this credit—not even in science classrooms or teacher break rooms.
Determine whether composting service with curbside pickup is available, or if the school is interested in onsite composting. Schools may also choose to throw away food scraps (or donate to pig farmers, if in the area) instead of using garbage disposals to meet this credit, but composting is the environmentally preferred method for managing food waste.
Onsite composting at the school is a great way for students to learn about waste, biology, and the environment. Schools can also add a garden project to make use of their composted food waste.
Some schools may be hesitant to eliminate garbage disposals in their kitchens and science classrooms because of their ease and convenience in dealing with wastes such as dissection projects. Host a discussion about the garbage disposal issue with school personnel early in your planning process. Most school staff can be convinced to eliminate the garbage disposals once an acceptable alternative has been proposed.
A food pulper or other food waste reduction system that pulverizes food and separates out the solids from the water can allow schools to eliminate garbage disposals and still limit the amount of food waste created. Solid waste can be reduced by up to 80%, and the remaining food waste can be composted or sent to the landfill.
Refrigeration equipment that uses once-through cooling with potable water must be eliminated. Discuss this with your project’s mechanical engineer and kitchen consultant to determine the availability of compliant refrigeration equipment. Generally, this is an easy requirement to meet.
Earning this credit can lead to not only reduced water and sewer bills, but may also reduce gas and electric bills due to reduced water heating and pumping.
This Fisher Ultra-Spray pre-rinse spray valve uses just 1.2 gpm, well below the 2006 federal maximum of 1.6 gpm. Photo – Fisher Manufacturing Research process equipment that meets the water usage requirements for this credit. Find out what is on the market and what makes the most sense for your project. Most projects find compliant products relatively easy to find, but it may require some flexibility. For example, one school had trouble finding a compliant 12-tray food steamer, but were able to purchase two compliant 6-tray food steamers.
To follow the prescriptive path, choose four of these five equipment types and meet the given water use requirements.
Ice machines must not only meet water-efficiency requirements, but they must not be water-cooled. This is part of the credit language, athough it is easy to overlook.
All steamers must be boilerless. Research compliant products that also meet the water efficiency standards.
Check the Consortium for Energy Efficiency website, which has a list of products and their associated water efficiencies for clothes washers, dishwashers, ice machines, pre-rinse spray valves, and steamers. (See Resources).
Check the Energy Star website for clothes washers, ice machines, and food steamers. (See Resources.)
Check the Food Service Technology Center’s website for pre-rinse spray valves. (See Resources.)
Purchasing water-efficient equipment sometimes involves a slight cost premium, but as these products become more popular, the price is expected to drop. These products should not be difficult to locate.
Research local and federal incentives and rebates on purchasing low-water-consumption products.
Many water-conserving appliances are also Energy Star-certified and will save not only water but also energy. Energy Star appliances often qualify for rebates.
You have the option of using an alternative compliance path through process-water equipment other than that named in the credit language. In order to do this, you need to demonstrate a 20% reduction of process water use from a baseline case. The baseline case is usually an industry standard, which can be obtained from your mechanical engineer or kitchen consultant.
Consider setting process-water reduction goals higher than this credit’s requirements. Achieving a 40% reduction in process water use can earn an exemplary performance point.
Research equipment that can reduce water consumption. Possibilities (in addition to the items listed in the prescriptive path) may include:
Alternative equipment types can be combined with any of the process-water items listed for the credit as long as you demonstrate a 20% reduction.
Running calculations to show a 20% or 40% reduction in process water use is more difficult than simply choosing a set of compliant products. The baseline must be determined by the engineer, who should choose a defensible number and avoid being too subjective.
Verify that none of the following have been included in any portion of the project:
Determine the four categories of equipment for which you will specify products that meet the thresholds, if following the prescriptive path.
Credit-compliant products are typically easy to find.
Collect information on applicable pieces of equipment, including equipment name, make or model, water usage, maximum allowable usage, and number of products installed. You’ll need this information when you’re ready to submit documentation to LEED Online.
If following the alternative compliance path and including equipment beyond the five types for which LEED establishes a baseline, look for options that work with your design and program needs. Evaluate a number of possible scenarios for achieving the credit.
Why would a project choose this path? For example, it might not be installing clothes washers or food steamers, which would not give it four compliant process water equipment types. In this case they will need to calculate a total reduction for their dishwashers, ice machines and pre-rinse spray valves. If their calculations do not meet the 20% reduction requirement, they will need to include other process water equipment types in their calculations. Projects that want to achieve an exemplary performance credit will also need to run these calculations.
Determine an acceptable baseline case—usually an industry standard that can be obtained from your mechanical engineer or kitchen consultant. This is evaluated on a case-by-case basis, so you need to provide a narrative addressing the rationale for your baseline numbers.
Select equipment that reduces process-water use.
Run calculations to verify a water reduction of at least 20%, and save them to upload on LEED Online as documentation.
Include compliant process-water equipment in construction specifications.
Fill out the LEED credit form, including equipment name, make or model, water usage, maximum allowable usage, and number of products installed. The designer needs to sign off confirming that no refrigeration equipment using potable water for once-through cooling has been installed.
The contractor needs to ensure that the correct equipment has been purchased and installed correctly.
Apply for water-use reduction incentives or rebates through your municipal water authority.
Provide building managers with manuals for unconventional products.
Consider installing permanent water metering for ongoing monitoring of the project’s water use. A submetering system can help to detect problems early and facilitate future LEED-EBOM certification.
If your project will be composting, research local compost haulers or onsite composting strategies.
Excerpted from LEED 2009 for Schools New Construction and Major Renovations
To maximize water efficiency within buildings to reduce the burden on municipal water supply and wastewater systems.
To receive this credit, buildings must have the following:
Assess the process waterProcess water is used for industrial processes and building systems such as cooling towers, boilers, and chillers. It can also refer to water used in operational processes, such as dishwashing, clothes washing, and ice making. equipment needs for the project, based on programmatic considerations and size of the school. Specify the use of high-efficiency equipment, appropriately sized, to reduce the potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. demand.
CEE is a North American nonprofit organization that works with its members to promote energy-efficient products, technologies, and services. CEE brings efficiency program administrators together, providing a forum for them to explore common interests, exchange information, and seek consensus with their colleagues as well as industry representatives and Energy Star staff.
Energy Star is a joint program of U.S. EPA and the U.S. Department of Energy that promotes energy-efficient buildings, products, and practices.
WaterSense is a U.S. Environmental Protection Agency program designed to encourage water efficiency in the United States through the use of a special label on consumer products. It was launched in 2006. The WaterSense website offers information on certified products, and other water conservation information from its partners.
Use this resource to find low-flow prerinse spray valves.
The following links take you to the public, informational versions of the dynamic LEED Online forms for each Schools-2009 WE credit. You'll need to fill out the live versions of these forms on LEED Online for each credit you hope to earn.
Version 4 forms (newest):
Version 3 forms:
These links are posted by LEEDuser with USGBC's permission. USGBC has certain usage restrictions on these forms; for more information, visit LEED Online and click "Sample Forms Download."
Documentation for this credit can be part of a Design Phase submittal.
Where can I find a benchmark or industry standard for the below equipments in kitchen. Although the supplier claim that they are based on the current technolgy to reduce the water consumption but difficult to calculate the 20% water reduction.
1. Flight dishwashers: we are not proposing that dishwashers with racks or baskets are used but have specified ‘flight’ dishwashers which run on a continuous belt, which are more suitable for the number of meals involved. These use 165 litres per hour to wash up to 3,800 plates, bowls, etc., per hour.
2. Pot washing machine : water consumption (maximum) 5.8 litres per cycle.
3. Combination ovens: steamers not used but 10-grid and 20-grid combination ovens will be included (the number of grids relate to the maximum number of 1/1 gastronorm cooking trays/pans the oven can accommodate). These use 6.3 and 12.5 litres of water per hour respectively
4. Water washing system : a manually operated water washing system is proposed for the ventilation canopies above the main cooking equipment. This will be used on average once per month and the washing process uses 35 litres of water per wash cycle.
Does anyone know of a rule that states you cannot include harvested Rainwater in your WEc4 calculations?
As part of our submittal for an Innovation Point for Process WaterProcess water is used for industrial processes and building systems such as cooling towers, boilers, and chillers. It can also refer to water used in operational processes, such as dishwashing, clothes washing, and ice making. Use Reduction in an Industrial Facility (a facility which uses far more process water than a school ever could) patterned after the credit for Schools, we added the fact that Rainwater will be harvested and used which accounts for approximately 12% of the more than 25 million gallons that will be saved annually. Part of the GBCI reviewers response was:
"Note that the rainwater collection strategy would not be applicable to an ID pursuit for Process Water Reduction; therefore the water savings reported for the rainwater collection system has not been taken into account for the purposes of this credit review."
I have searched through every LEED Reference Guide, Addenda, CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide's, and LEEDuser. I cannot find anything that confirms (or denies) the reviewer's comment. Can anyone point me to where they got this?
Thanks - Kris
I don't know of anywhere it's written that rainwater collection can or can't contribute to an ID credit in this way. In my opinion, it should be allowed, because the process waterProcess water is used for industrial processes and building systems such as cooling towers, boilers, and chillers. It can also refer to water used in operational processes, such as dishwashing, clothes washing, and ice making. is outside the scope of reguar non-ID credits, and yet rainwater is an allowed strategy in meeting those credits. It meets the key tests of ID-worthiness.
However, with ID credits there is typically not a lot of precedent or written rules.
You could appeal, or submit a CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide.
Has anyone found dishwashers other than thermador that can meet this
Suzanne, we list nine different companies with compliant products in our GreenSpec directory—see the sidebar up and to the right of this forum.
Some locales require drain water temp to be under 110 degrees. A commercial dishwasher may expel water up to 150 degrees--higher if drained right away, all tanks at once. Has the USGBC taken a stand regarding the use of drain water tempering and the potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. it uses? Thanks!
Suzanne, I have not seen this referenced in any LEED requirements. The typical approach is to regulate individual appliance efficiency.
What you describe is similar to the issue of once-through coolingA once-through (single pass) cooling system is one which water from any source is used to transfer heat from equipment or processes and then discharged. with potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems., which this credit does cover, but it's a different issue.
Suzanne, it's a good question, drain water tempering can lead to significant water use. As Tristan mentioned, this is not referenced in any LEED requirements. The latest version of LEED BD&C 2012 does not addressed it either.
Water use from drain water tempering seems to fall outside of the water use testing criteria for the Consortium for Energy Efficiency and Energy Star, which both certify dishwasher water use.
It seems like an ideal strategy in this scenario would be adding a drain water heat exchanger to capture the heat for another use and eliminating the need for using potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems..
Great comments. If the drain water heat recovery encompassed all hot discharge water, i.e. from steamers etEvapotranspiration (ET) is the loss of water by evaporation from the soil and by transpiration from plants. It is expressed in millimeters per unit of time. al, that would be great. I researched drain water heat recovery for a utility in Canada about a year ago, but there were issues, in particular because there isn't enough water to 'get' anything out of. Waste AIR heat recovery is increasingly common in commercial warewashers, and those machines are fed with cold water. But alas, the water heated with waste air, then maintained by tank heaters, then has to be cooled! It's a problem. I wondered if a food waste digester discharge might work? (aerobic digester which converts food waste into 'water.')
You can also get lower-temperature dishwashers, but you have to use more chemical sanitizer (chlorine, etc.), so there is a tradeoff.
The intent for this credit is "To maximize water efficiency within buildings to reduce the burden on municipal water supply and wastewater systems."
The principal at our school was not willing to eliminate garbage disposals based on concerns about health-safety and food scraps. However all wastewater is treated on-site in a sewage pond. Would LEED allow garbage disposals if we are not tied to a municipal wastewater system?
It might be worth it to review WEc4.3 under LEED for Healthcare. They actually allow disposers if under full load they use 3-8 gpm, and under 1gpm no load, with a ten minute shut off timer. Would your principal allow a pulper? That's one of the best because it will take items other than food waste.
Does anyone have an idea what process waterProcess water is used for industrial processes and building systems such as cooling towers, boilers, and chillers. It can also refer to water used in operational processes, such as dishwashing, clothes washing, and ice making. using appliance could be considered "other?" i.e. a pulper, waste collector, both alternatives to disposals? If so, can the baseline potentially be LEED for Healthcare because it has baselines already set in that track? Thanks.
Suzanne, I don't know what is meant by "other," but it does seem logical that LEED for Healthcare could be used here.
Has anyone attempted to utilize a scrap collector when attempting WE4? It recirculates the water it uses, reducing supply water usage by 90% over traditional garbage disposals. It would then grind the fibrous & non-soluble food waste and reduce waste bulk by 50% - 80%, reducing the amount of disposed waste. The client is not willing to compost everything, but we are attempting to get them to compost the pre-consumer waste (kitchen scraps, etc) thus reducing the amount that would be put in the scrap collector, and further reducing the amount of process waterProcess water is used for industrial processes and building systems such as cooling towers, boilers, and chillers. It can also refer to water used in operational processes, such as dishwashing, clothes washing, and ice making. needed to eliminate food waste. Has anyone else attempted a similar approach?
Many of my foodservice consultant clients specify collectors. Under LEED for Healthcare (Pilot), collectors are addressed. I would imagine that someone may have presented collectors as alternate compliance path, but compared to a pulper, at 2 gallons per minute, the collector is not the "best." Larger operations have difficulty with collectors because they must be emptied, and there is lifting involved. Collectors also offer up somewhat of a pre-rinse with their gusher heads, and using recirculating water.
I see that there is a subtle change in WEc4 in LEED v3.0 over v2.2 that has some of my food service consultant clients very concerned. And with good reason because their kitchen's performance can be severely affected, and they are largely responsible for achieving this credit.
Under the previous version, four of the five processes, IN AGGREGATE, reducing water collectively by 20% was the means to get the credit. Now, each individual item has to be 20% lower than standard. Many food service designers would agree that today's boilerless steamers frequently do not provide the production needed for a school. But if they could use the best in class steamer WITH a boiler, for instance, that actually worked for the school, and made up the difference using lower water usage "everything else " for a total 20% water usage reduction, why wouild that not be considered as the intent of the credit?
Door-style dishwashers that use less than one gallon per rack are generally undersized for schools, even for those using door-style machines now. There is a drop in production from 55 or so racks per hour, down to 38, so run time is longer, so potentially higher energy costs, not to mention labor. I had one client specify two smaller clothes washers rather than the one larger unit, because the smaller ones met the standard, the larger did not, but the two together exceeded the water and energy for the one larger model. Another specified an ice machine in a school that didn't need one to get this credit by having 4 of the process waterProcess water is used for industrial processes and building systems such as cooling towers, boilers, and chillers. It can also refer to water used in operational processes, such as dishwashing, clothes washing, and ice making. users. Besides, schools take very good care of their kitchen equipment, so they are stuck with the decision for at least 20 years. Nugget ice makers, at 12 gal/100#, rather than cubed ones at 20, significantly make up the deficit while keeping the kitchen high performance. Therefore, properly sized dishwashers and steamers are possible.
What is the rationale here? Better, what is the answer? It seems to me that the consultant can't make a correct decision--if they pass on the credit, they look bad, but if they specify products that don't work, they look worse.
I hear ya!
I think it makes sense that the requirements should be able to be met through a combination of efforts as opposed to having to have each individual item meet the requirements. I can't answer your question regarding the GBCI's rationale though I can suggest that you'll probably have to follow the requirements of the credit as its currently stated if you'd like to get the point.
Alternatively, you could submit a project specific CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide.
Latest addenda for the credit is here: http://www.usgbc.org/ShowFile.aspx?DocumentID=7054 which just further clarifies that you must include "at least 4 process items" with "all appliances within at least 4 equipment types."
As a consultant I generally try to follow the intent of the credit and try my best to meet it. I also try to remind my clients that, even if the point isn't earned, we should still try our best to do the "right" thing. This usually means, deciding your priorities and goals in terms of LEED Certification level and then doing what you think is both reasonable and most beneficial for our planet.
Sometimes, you need to follow the LEED requirements in some instances and diverge in others.
Where do you see this change from a 20% reduction on all equipment to a 20% reduction on each piece of equipment? As I read it, we are still allowed to calculate a 20% reduction based on an aggregate number.
Shannon, please see Lauren's link above. But the real way to clarify it is with the online template at LEED Online. If you would like to send me your email address, I will forward the old template to you with some specifics plugged in, and you can plug the same figures into the online template that I have NO ACCESS to. This is why the USGBC really needs to make the letter templates at LEED Online available to at least members, because not all of us have an active LEED for Schools project, OR, we do and we just don't have access. Bottom line, if we plug the same figures in, and it comes up with the point, then nothing has changed.
I do not see the difference Suzanne is noting for this credit’s requirements either. If it is in fact a difference between the v2009 Form (formerly known as a Template) and the credit’s requirements, this should be reported to USGBC LEED Resource Development for a fix to the Form. I do not have access to the Form for Schools v2009 and cannot confirm the calculations. Looking at LEED Online v3 Help (new and improved - https://www.leedonline.com/irj/go/km/docs/documents/usgbc/leed/config/co...), a new version of the WEc4 Form was released on 8/20/10. I wonder if Suzanne’s consultants were using the Beta Version of the Form previously as her post is dated 8/20/10. If the problem exists in the new version of the Form, it should be reported as flawed.
Because the USGBC no longer has the forms, previously published under 2.0/2.2 as "sample templates" ,http://www.usgbc.org/DisplayPage.aspx?CMSPageID=1447
for LEED 3.0, but continue to have on their site those for LEED 2.0, 2.2, see link above, we have no way of checking it. My point is that you used to be able to COMBINE the water usage for the four of five process items, steamer, dishwasher, ice maker, pre rinse spray and clothes washer, which in TOTAL had to reflect a 20% reduction in water usage. So, if a consultant spec'd an ice maker that was over the baseline, but made up for it with another piece, he'd get the credit. NOW, EACH OF THE FOUR items, of the five to choose from, must in of itself, stand alone as each being 20% below baseline. I was told this by a consultant on a project whose architect kicked it back. While language is not totally clear I told her that the only way to check it would be to access the template on LEEDOnline and plug in some numbers, to test the old scenario. Dishwasher standard is one gallon per rack. Easy to exceed on a rack conveyor machine, but harder on a door style machine. So if you spec a door because that is all the customer needs, at say .91, you aren't 20% below. But your ice maker standard is 20 gal. per 100 lbs. of ice. So if you spec'd an ice maker using 12, you'd drastically cut the water usage, easily making up for the short fall for the dishwasher. Under 2.2, you'd get the credit. Under 3.0, I am told that you would not because the door machine isn't of itself 20% below baseline. I want to be wrong on this, but until I can see that template for myself, plug in numbers for four pieces of equipment, deliberately making one NOT be 20% below baseline, while the total of 4 together as a package IS 20% below or better, I can't tell if you'd get the credit. I have tried and tried to get access to this but I am not on a project right now. So if anyone out there in LEEDUser-land can access the WEc4 template on LEEDOnline, I will happily supply numbers to try this out. I can't tell if there's a flawed form if I can't see the form. The CaGBC, unlike the USGBC, publishes their LEED 3.0 sheets in an xls workbook. NICE! Sadly, they don't have a LEED for Schools, or I'd check there.
I can access the WEc4 template for schools. If you still want/need it, let me know how to get it to you.
I would deeply appreciate it. I am doing a class next week and don't want to mis-inform anyone. email@example.com . Many thanks.
Thanks to Kasey (my new best friend), here's what I found when using her template: a. the 20% reduction is built into the baseline, i.e. see LEED Retail, which is higher. This is NOT clear in the credit language which implies that you beat the drop-down by 20%; b. there are two categories for ice makers based on poundage, so you can have two ice makers, one in each category and they count separately, as opposed to two dishwashers, which was attempted by another user above. Sadly, it takes more water an energy generally, to run two ice makers this way than one larger, more efficient one. As opposed to LEED 2.2, all and each of the products must be AT the standard in the template, or below, but in 2.2, one could be out of range as long as the total reflected 20% savings.
I recently had this credit denied by GBCI and the logic they used was unsettling.
Our clarification request stated: stated: “The LEED Submittal Template has been provided stating that the project has maximized water efficiency within the building through the installation of ice machines, dishwashers, and pre-rinse spray valves. The Submittal Template indicates that no refrigeration equipment was used in the project that uses once-through coolingA once-through (single pass) cooling system is one which water from any source is used to transfer heat from equipment or processes and then discharged. with potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems., and that no garbage disposals are installed on the project. The Template also indicates that all process waterProcess water is used for industrial processes and building systems such as cooling towers, boilers, and chillers. It can also refer to water used in operational processes, such as dishwashing, clothes washing, and ice making. use equipment is less than or meets the maximum water use LEED allowable limits.
However, per the requirements listed in the LEED for Schools v2.0 Reference Guide for WEc4, the project must include at least 4 process items. Please note that while the project has listed 5 pieces of process equipment that meet the water use levels, only 3 categories of process equipment are listed. Each category of process equipment may only be counted once towards the credit requirements, because it is assumed that each piece of process equipment in each category meets the water use level requirements in full. This same implication requires that all process equipment included in the project under each category must meet the water use level requirements.
TECHNICAL ADVICE: Please provide a revised Template demonstrating that the project includes at least 4 categories of process water equipment in which all equipment in each category meets the water level use requirements for this credit."
I contacted Christopher Davis at GBCI who then contacted the WE TagLEED Technical Advisory Group (TAG): Subcommittees that consist of industry experts who assist in developing credit interpretations and technical improvements to the LEED system.. He wrote: “I have confirmation from the Water Efficiency Technical Advisory Group that “item” in the credit requirements is intended to refer to a category of items. This is intended to prevent, for example, projects that may have 5 dishwashers when only one meets the credit requirements. Note that the credit also allows you to propose your own benchmark against which to compare equipment that could be used to meet the requirements...”
We attempted to build a case around this and even contacted USGBC Schools staff who believed we had made a good case and said they would go to bat for us on this. We wrote in our clarification response memo: “While we both acknowledge and agree with the logic of this clarification to avoid unintended consequences, we designed the project under the assumption that we needed 4 process items. In addition, we worked hard to design the project’s kitchen to meet the requirements of this credit including no garbage disposals and no refrigeration equipment using once-through cooling with potable water. We then followed guidance in the Reference Guide to assess all processes in the building that used water to identify opportunities for selecting high-efficiency equipment. All items in the categories of commercial dishwashers, ice machines (both classes), and pre-rinse spray valves at XXXX meet the credit requirements. We do not have any commercial clothes washers on the project. We do not have any food steamers on the project and purposefully eliminated this equipment category due to its water intensive nature. As far a commercial water using equipment goes, we do have a combination oven that does both convection cooking, steaming, and a combination of both but since it is not just a “food steamer” we would have to come up with another water use benchmark. Upon investigation we learned from our Food Service Consultant that we could not find a water efficient model although our combi oven is boilerless. So unfortunately we cannot propose a benchmark for that piece of equipment. We do not have any other new commercial process water using equipment on the project.
In order to meet the reviewer’s request to have another category, we looked throughout the school for water using equipment. We do a have a residential dishwasher in the Family and Consumer Services classroom. In light of our water conserving ethic for the school, we went to great lengths to specify this residential dishwasher as energy and water efficient earlier in the project. We utilized BuildingGreen’s GreenSpec category of residential dishwashers when specifying it. It states: “Most of the energy consumed by dishwashers is used to heat the water; therefore, water-efficient dishwashers are also energy-efficient. As with other home appliances, national energy standards have catalyzed the development of more efficient dishwashers. As a measure of efficiency, the Energy Factor (EF) describes energy performance under carefully defined conditions, and provides a basis of comparison among different models. The national energy standard requires all regular size dishwashers to have an energy factor of at least 0.46. The Energy Star program qualifies dishwashers exceeding that standard by at least 25% (EF of 0.58)….”
GBCI responded when they denied our credit: “The project team has provided a revised Template demonstrating that the project has included 3 categories of process water equipment (ice machines, dishwashers, and pre-rinse spray valves). A supplemental narrative has also been provided to describe the project's strategy for attempting this credit.
However, while the Template and narrative demonstrate that all six process water equipment items meet the water level use requirements for this credit, the project has not demonstrated that at least 4 categories of process water equipment have been included on the project, as required. Please note that the Residential Dishwasher is not considered a category separate from "dishwashers." Please also note that while the project's strategy for attempting this credit is commendable, not all credits apply to all projects. The documentation does not demonstrate credit compliance.”
They had no idea how much effort we went to get the district to remove garbage disposals in the kitchen and well as the lengths we went to adhere to all the credit requirements and then they changed the requirements on us. I hope no one else has this experience. Our team decided to not pay the $500 to appeal this because we felt it was a waste of money.
How very unfortunate. Your team clearly had a solid grasp of the intent of the credit, met it (in my opinion) and documented it adequately. It is very frustrating when nuanced interpretations are made and appeal is the only remedy. Though you understandably chose not to appeal the decision, there may be value in forwarding this experience back to the TAGLEED Technical Advisory Group (TAG): Subcommittees that consist of industry experts who assist in developing credit interpretations and technical improvements to the LEED system. and USGBC staff for informational purposes, as it would at least suggest that this credit requires clarification. In my view this is one reason why the current CIR process (not posting them) is not satisfactory; It does not allow for "daylighting" difficult issues or provide a method for educating future users. Thank you for sharing your painful experience with other interested LEED users.
This info may be too late to act on, but I was looking for info about GPM vs. GPH for WEc4 and downloaded the latest (Nov. 3 2010) addenda for LEED for Schools v.3.
The Addenda Item that would help you was posted on 7/19/2010 well after your credit was rejected and states for WEc4: In the first line of the third bullet item, replace "At least 4 process items" with "All appliances within at least 4 equipment types"
The USGBC Addenda website states "Project teams are required to adhere to the Rating System addenda based on registration date." That requirement should not apply to your project which was submitted prior to the addenda. I would make a big deal about it. GBCI should be required to follow the rules established by USGBC and not make up the rules as they go.
Patricia – Thanks for directing me to this resource (and thanks Tristan for pointing me back to Patricia’s comment).
I just realized that my inquiry was posted under LEED 2009 but the credit was actually denied under LEED for Schools v2.0. Sorry I did not make that clear at the top of the post. The language of the credits was the same in both versions until the 7/19/10 addendum item for WEc4 (http://www.usgbc.org/ShowFile.aspx?DocumentID=6392 (see page 21)).
That addendum item is a great clarification for LEED for Schools 2009 teams; however, I don’t think that this would change the situation for my project (even if I could utilize an addendum item from another version of the rating system to set precedent). Maybe they even used our project as a reason to change the language?
I think USGBC has greatly improved the requirements and made it clearer for other teams though and this will help them avoid a situation like we had (we only had 3 equipment types – not the now required 4 – but we had addressed all appliances within those 3 equipment types for a total of 5 process items). I still think we got a raw deal but we’ve moved on and I’m glad other teams won’t have to have this credit denied thanks to the new language.
If in the school kitchen there is a dishwasher with the required performance and no one of the other 4 water consuming equipments listed in the requirement, together with the compliance to the other requirements, can we get the credit?
The best "process waterProcess water is used for industrial processes and building systems such as cooling towers, boilers, and chillers. It can also refer to water used in operational processes, such as dishwashing, clothes washing, and ice making. use reduction" is no-use at all process water, isn't it?
Excellent question. As you point out the best reduction of resource use is no use of resources.
Per the LEED Schools reference guide, this credit calls for using 4 process waterProcess water is used for industrial processes and building systems such as cooling towers, boilers, and chillers. It can also refer to water used in operational processes, such as dishwashing, clothes washing, and ice making. items at established industry standard or lower which is quite definitive. Most often such definitive criteria in LEED dictates a very clear interpretation.
However, there is also precedent with other LEED credits such as EAc4, Enhanced Refrigerant Management, where credit is achieved if no refrigerants are used because there is no environmental impact—same concept. Your question has identified a "grey" zone and needs to be interpreted for intent.
I first recommend determining whether you have any additional process water uses in your project that are NOT on the list in WEc4. If you do have any additional uses not on the list, and can document that the rate for the items you are specifiying is 20% or below the industry standard, these items can count toward the 4 of 5 required items.
If you do not have any additional water process uses and you are able to demonstrate that by project program and goals your team consciously chose not to introduce process water elements to reduce impacts, your approach may satisfy the intent of this credit. To determine this definitively, you need to pursue an interpretation through your LEED Review Team, who is assigned when you register your project. (The former process for credit interpretations was through a Credit Interpretation Request, however, this is no longer available with LEED 2009).
Good luck and be sure to post your LEED Review Team’s response on LEED User so we can all learn from your experience.
The credit language says to avoid "once-through refrigeration" equipment, which could mean chillers, I suppose, but from the context seems more likely to be about food refrigeration. The Reference doesn't say anything at all to clarify this, except that it shows a cooling tower in the "examples" section.
I guess, since there are no calculations for this credit but just a list of fixture types to prefer/avoid, you'd have to avoid once-through coolingA once-through (single pass) cooling system is one which water from any source is used to transfer heat from equipment or processes and then discharged. towers as well to claim the point. Does that seem right?
Yes, you are correct in assuming that that once-through coolingA once-through (single pass) cooling system is one which water from any source is used to transfer heat from equipment or processes and then discharged. must also be avoided in cooling towers, as well as with other refrigeration equipment.
I know this response is dated, but as a Cooling Tower manufacturer and the LEED AP on staff here, I need to provide my input.
1) There are no once through cooling tower designs, at least if operated properly. Cooling towers were designed to recycle water, and conserve 95% of the water in an evaporatively cooled system. Cooling towers replace once through systems to conserve this cooling water.
2) Item 8 Examples, in LEEDv3 WE Credit 4, the statement of the closed loop system in a cooling tower is not entirely correct. There are open cooling towers, and closed circuit coolers, open vs. closed systems. Potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. use is based on the amount of evaporation that is taking place in the closed loop cooler or open cooling tower, and evaporation loss is based on the heat load from the building that is sent to the tower. A closed loop cooler or open cooling tower will evaporate the same amount of water with the same heat load. It is true that using a closed loop cooler keeps the system clean, but this just helps with fouling in the system, and does not necessarily save water.
Our local water utility encourages the collection of condensate to make up evaporation loss. It seems we should be able to count that towards the 20% reduction for path 2 above. Has ayone tried this approach?
Alison, though I have not used this path yet, I do think you should give it a shot. Be sure to include documentation to support the quantity of condensate collected, a clear description of how it is recycled and displaces potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. use in the cooling tower, show your calculations in gallons per minute as is standard for cooling towers, and determine percent reduction. The credit requires 20% reduction from standard, so you'll need to do calcs to see if you can meet that benchmark. Good luck!
If your project will be doing M&V, consider metering process water uses.
Do you know which LEED credits have the most LEED Interpretations and addenda, and which have none? The Missing Manual does. Check here first to see where you need to update yourself, and share the link with your team.
LEEDuser members get it free >
LEEDuser is produced by BuildingGreen, Inc., with YR&G authoring most of the original content. LEEDuser enjoys ongoing collaboration with USGBC. Read more about our team
Copyright 2013 – BuildingGreen, Inc.