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Northampton GZA GeoEnvironmental Inc. Preliminary Hydropower EvaluationOne Edgewater Drive Norwood Massachusetts 02062 781- 278 -3700 FAX 781 -278 -57(11 htt J= i71ti`tNW a.c.1102 GZA :aeofimvironntentril., Inc, September 22, 2009 File No. 19547.10 Mr. James R. Laurila, P.E, City of Northampton Department of Public Works 125 Locust Street Northampton, Massachusetts 01060 Re: Preliminary Hydropower Evaluation Upper Roberts Meadow Reservoir .Darn Northampton, MA Dear Mr. Laurila: Engineers and Scientists In accordance with your request GZA CieoEnvirontwmtal Inc. (GZA). of Norwood, Massachusetts has completed our preliminary hydropower resource assessment for the Upper Roberts Meadow Reservoir, located in Northampton, Massachusetts.. The purpose of our efforts .was to provide' you with a preliminary assessment of the potential for hydropower generation. at Upper .Roberts Meadow .Reservoir Darn. As part of this assessment GZA developed estimates of the theoretical hydropower generation capacity and annual energy production potential based on typical available flows and available head at the dam. GZA also grossly estimated conceptual development costs and calculated the simple payback period for the project based on assumed energy values. This letter report is subject to the limitations included in Appendix A. SITE DESCRIPTION Upper Roberts Meadow Reservoir Dam is situated on Roberts Meadow Brook in the Leeds section of Northampton, Hampshire County, Massachusetts..Thc dam is situated off Chesterfield Road, The darn's impoundment is referred to as Upper Roberts Meadow Reservoir. The clam was originally constructed as part of the City's water supply system. but no longer is relied on as a water supply reservoir and serves as part of the backup water supply system. The Elam is an earthen embankment with a stone masonry spillway. The dam has a height of about 35 ft and a length of about 125 ft. An approximately 65 -ft -long stone block masonry broad crested spillway is located near the dam's lett abutment, The spillway is arch shaped, and. a 27 -ft long portion of the spillway near its left abutment is notched, about 6 inches lower than the remainder. The contributing drainage area at the dam is approximately 9 square miles. A site locus is included as .figure 1. Copyright`'' 2009 GZA. GeoEn.vironmental, Inc. City of Northampton GZA File No, 19547.10 Preliminary Hydropower Evaluation September 22, -2009 HYDROPOWER ASSESSMENT GZA is familiar with the dam from our work on the 2006 Phase I Inspection and 2007 Phase II Inspection and Preliminary Dam Removal Design and Permitting. GZA estimated the power generation capacity and the average annual energy as part of our alternative when considering whether to repair or remove the dam. The average annual energy is an estimate of the amount of energy that could be generated in a year by the project assuming average hydrologic conditions. We then investigated the approximate costs involved with the design and installation of hydropower generation equipment and estimated the simple payback period, Payback periods were calculated for electricity at wholesale value (i.e. sold to the grid) since the city does not have the need for power at the dam site. Hydropower Hydrology alien Hydraulics Although the Upper Meadow .Dam has a surface area of approximately 4 acres and a storage capacity of approximately 6.6 million gallons, a potential hydropower project at the site would need to be operated as a nn -of -the river project (i.e. flow into the impoundment equals flow out without significant water level fluctuation). It is unlikely that operation as a peaking project (i.e. utilizing the storage in the impoundment to store water and generate electricity at times when electricity rates are high) would be granted approval by perthitting authorities. GZA. developed a tl.ow duration curve for the site based on flow records collected by the l.7SGS. for Station Number 0II71500, Mill River near Northampton, MA. The USES gaging station is located approximately 6 miles away. GZA utilized a drainage area ratio to estimate flows at the Upper Roberts Meadow Dann. GZA estimated that the median (50 percent excccdence) flow is approximately 10 cfs and that the 25 percent duration exceedence flow is approximately 20 cfs. A copy of the flow duration curve is included as Figure 2. Because hydropower turbines are typically sized for approximately the 25 percent. duration flow the maximum design flow was taken to be 20 cfs. Note that a conservation flow has not been assumed. Requirements for a conservation flow would results in a decreased maximum design flow. Power and Energy Estimates The amount of power that can be produced is controlled by the net head available, the flow available to spin the turbine, and the overall efficiency of the hydropower system. Based on our observations of site conditions, the available hydraulic head is approximately 24 feet. The maximum design flow was taken to be 20 cfs. Based on the flow and head available for the project, a 'ross:flow or a Kaplan type turbine may be an appropriate choice. GZA assumed. efficiencies based on efficiency curves 7 Power (kW) Energy (tiiWhrI 30 130 Value of Energy Value of RECS Annual Value of Energy 7,800 5,200 13,000 Cost to Design and Construct Project 750,000 to 1,000,000 Simple Payback Period mars` -55 to 77 City of Northampton. GZA File No. 19547.10 Preliminar Iivdr ower Evaluation September 22, 2009 provided by manufacturers for projects of similar size. GZA estimated a maximum power output of 30 kW and an annual energy production of 130 MWh. .Project Costs and Payback Period GZA developed gross preliminary conceptual estimates for the costs involved with the design and .installation of hydropower generation equipment. Preliminary conceptual estimates indicate that it will cost. between approximately $750,000 and $1,000,000 to .design, permit and build the proposed hydropower project at Upper Roberts. Costs will be impacted by the distance to the utility tie -in to the electric grid, necessary licensing and permitting efforts, actual equipment costs, and other factors. No costs for environmental mitigations (such as a fish ladder) have been. assumed. Costs to develop the project have been assumed to benefit from significant `synergy in constructing the project at the same tirne as repairs to the dam. The cost to repair the dam ($1.8 million) is assumed to be independent o'fthe cost to develop the hydropower project and is therefore not included in the payback estimate, GZA evaluated the value of the energy produced on an annual basis. Because the location of the dam is remote (i.e. there is no end -user for the electricity) at the site, we evaluated the scenario where the electricity is sold to the grid and thus the City would receive wholesale value (approximately $0.06/ kWh) for the electricity. We have also assumed that the project will be considered to meet the Massachusetts Renewable Energy Portfolio Standard and that Renewable Energy Credits (RECs) will be worth $0.04 /kWh. Note that in this analysis, GZA has not attempted to account to for the future value of money, interest variable electricity costs, or tax incentives, The following table summarizes the annual value of energy produced for wholesale values. Tablet. Annual Value of Eller Produced The most recent hydropower solicitation from the Renewal Energy Trust (RET- formerly known as the Massachusetts Technology Collaborative) was announced in September 3 City of Northampton GZA File No. 19547.10 Preliminary Hydropower Evaluation September 22, 2009 2009, The solicitation requires that all projects must "result in an increase in energy generation by at least 200,000 kWh/year, on average, as compared to historical levels." The solicitation also requires that the project: 1) have a FERC license or exemption, 2) have a FERC RC order indicating the facility is non jurisdictional to FERC, 3) or be eligible for a conduit exemption. Based on our estimate of annual energy potential and the fact the project does not meet the FERC status requirements, a hydroelectric project at the Upper Roberts Meadow Dam would not be eligible for a traditional grant from the R.ET through this solicitation. Discussion of Project Feasibility Based on a design flow of 20 cfs and a head of 24 feet, the maximum power output for a hydropower project at the Upper Roberts Meadow Reservoir Dam would be approximately 30 kW. During periods of lower flows (i.c. say 20 percent of the design flow), a minimum of 6 kW could be generated and during months of lowest flows (Le. August and September) generation would likely cease. An annual energy production of approximately 130 IVMWhr would be expected from a project at the site. This is enough energy to meet the needs of approximately 30 homes. Since there is not an existing FERC licensed or exempt hydropower project at the dam, the project would likely need to go through the Federal Energy Regulatory Commission (FERC) process to obtain a license. GZA anticipates that the FERC license process could take more than 5 years at a cost of more than $100,000 to secure the license required for a hydropower project at this location. Typically, small hydropower systems are more cost effective if there is a direct end user near the hydropower plant. The City does not have any power demands in the vicinity of the dam. If hydropower was installed, the generated power would need to be put back into the power grid. Power put back into the grid is only worth about 1/3 the value of the power if it were used on -site. Given the location of the dam, new transmission lines would need to be provided to get the power from the dam into the grid. This also adds cost to the project which consequently makes the option even less financially viable. C:1ZA preliminarily estimated a project payback time on the order of 58-77 years (excluding the cost of the new transmission lines). It is unlikely that a payback time of this duration would be considered acceptable to justify development of this project (from an economic standpoint). In addition, to install a small hydropower system, the darn would need to be rehabilitated to bring the dam into compliance with the dam safety regulations. Rehabilitation of the dam is approaching 2 million dollars. 4 City of Northampton GZA File No. 19547.10 Preliminary Hydropower Evaluation September 22, 2009 CONCLUSIONS Based on GZA' s preliminary feasibility evaluation of the potential hydroelectric generation at the Upper Roberts Reservoir we have the following conclusions. O The potential maximum power at the darn is approximately 30 kW and the potential annual energy is approximately 1 .30 M.Wh- ,enough energy to power 30 hottes. Q The City does not have any power demands at or near the darn site,. therefore the energy would need to be sold to the grid at wholesale cost (approximately 1/3 of retail value). The energy will have an annual value of approximately $13,000 (including income from the sale of REC:.$). it will cost approximately 8750,000 to $1,000,000 to develop the project. The project will have a payback period of approximately 58 -77 years. RECOMMENDATION Based on this preliminary analysis, the. assumed utilized current energy values, and CiZA's understanding of the goals of the City in developing alternative energy projects, we do not believe that the Upper Roberts Reservoir Dam is a viable hydroelectric project site. We trust that the information. contained in this letter meets your needs at this time. Please call Chad Cox (781-278-5787) with any questions that you may have. Very tartly yours, GZA GEOENVIRONMENTAL, INC. Kristin Ekholm, P.L. Wat k Resources Engineer 1 1/ tp t /1/ /lad. W. Cox, P.E. Principal-in-Charge Attachments: Appendix A: .Limitations Figures 5 M A. Taylor, P.E. Consultant/ Reviewer \19,000.20 999119547`.19547- I0.MATHydro Evaluation\ Preliminary _Hydro_Leitcr- 9- 14.09.DOC Alternative Energy Systems Developer and Integrator To: Friends of the Upper Reservoir Dam Re: Evaluation of Hydropower for the Upper Roberts Dam Dear Dee John, After looking over the information forwarded to me from GZA and per phone conversations concerning the Upper Roberts Reservoir dam, we believe that a hydroelectric plant would be feasible. After reviewing the data, the preliminary figures indicate that with minimal disruption to the historic dam site, a 50 -100 KW Kaplan style turbine generator could be installed. A feasibility study would have to be completed to determine the exact size hydro system to set in place. This would require a site visit to gather information on the site and surrounding area. This type of power plant could supply power for approximately 40 to 80 homes for one (1) year* and power over produced will be Net Metered to the grid. This over production will in essence pay for repairs and maintenance of the dam site. I have also sent along with this findings letter the following... Federal Energy Regulatory Commission brochure for small hydroelectric systems D R Energy Services affiliations list Also, I will be available to take your call if you require additional information in your meeting. Sincerely, Robert Craig Senior Engineer D R Energy Services, Inc. Alternative Energy Systems Developer and Integrator Office: (810) 229 -2390 Cell: (810) 422 -3275 www.drenergyservices.com Average annual household electrical usage in the United States is 10,000 KW, based on 2007 statistics from the U.S. Department of Energy. PO Box 1013 Brighton, MI 48116 www.drenergyservices.com Phone: (810) 229 -2390 (877) 766 -0664 LANDFILL METHANE OUTREAGI PROGRAM