Siting Considerations for Utility Scale Photovoltaic Power Generation Systems.Tim Green, Brookhaven National LaboratoryNE FWS Biologists ConferenceFebruary 16, 2011

On the AgendaIntroduction to SolarSiting considerationsIndustry viewEcosystem viewLong Island Solar Farm*

Why worry about Solar Development?EO 13514 Sec. 2 Goals for Agencies (a)(ii) increasing agency use of renewable energy and implementing renewable generation projects on agency property;One of the fastest growing energy sectors in the countryRequires a lot of land, 5-10 acres/MWMuch of NE is either built up, in farmland, or forest.NE is a good location for Solar PV

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Photovoltaics in the NortheastCompleted Projects*http://www.solarelectricpower.org/solar-tools/solar-data-and-mapping-tool.aspx

Photovoltaics in the NortheastPlanned Projects*http://www.solarelectricpower.org/solar-tools/solar-data-and-mapping-tool.aspx

Solar Energy Development*

*Info from: www.seia.org

*Utility Scale Photovoltaic Systems SitingSiting Considerations all projectsProximity to Grid shortest distance to grid tie point preferredLand costs requires 6-10 acres/MW (One large block of land preferred).Clearing minimize Construction want clear ground, must fence facilityOperations minimize maintenance efforts (cleaning, mowing, repair)

Utility Scale Photovoltaic Systems SitingSiting Ecological Concerns (Our Concerns)Proximity to GridClearingFinding suitable cleared land (brownfields, farms, etc.)Minimize forest clearingContiguous properties preferred (one large block better than many small blocks?)Avoid WetlandsAvoid Endangered SpeciesAvoid Migratory Birds or alter habitatSite preparationFencingVegetation

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Long Island Solar FarmThe ProjectSitingSolar ArraysDesigning in Sustainability and Ecological BenefitsEcological ResearchEnd of Life Considerations

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*Location

*The Project Aerial Extent

*Long Island Solar FarmSize: ~32MW (AC)Location: Brookhaven National LaboratoryTechnology: Crystalline solar photovoltaic modules Land use: ~200 acresConstruction schedule: Fall 2010 Fall 2011Project is one of 147 demonstration sites chosen for the Sustainable Sites Initiative see http://www.sustainablesites.org/pilot/

*Site Considerations - BNLProximity to electric substation grid tie pointLimit impacts to site operations and future scienceScientific study of array and PV technologiesImprove the environment; reducing carbon footprintStrengthen the local economyEncourage economic developmentTransform the solar photovoltaic marketplace

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*Current Configuration

SustainabilityForest Removal reduction of carbon sequestration ability ~12,000 Metric tons over 20 years.Carbon Avoidance - ~619,000 metric tons over 20 years.Understory retained will continue to sequester carbon and add to soil. (This isnt happening as planned)Minimal impact to soilsLittle or no water usageCommitments for recycling and pollution preventionHabitat Improvements (This may take longer)Vegetation Management IPM for invasives*

*Reducing Potential ImpactsRequires minimal grading resulting in less disturbance of understory vegetation (grasses will be planted)Tree removal timing and processWildlife friendly fencingNative vegetation planted or left under arraysInvasive species management - removal

*Positive Ecological Impacts200 acres of deer free areaRemoval of invasive plants protects surrounding areaMaintenance of native vegetation wide variability in make-up and density (Because grasses are being planted everything below may take longer to achieve.)Improved habitat for migratory birds Improved habitat for small mammalsImproved habitat for reptiles and amphibiansImproved habitat for insects?

*Ecological ResearchImpacts to vegetation make up and healthShading effectsPrecipitation effectsHeat island effectsImpacts to soils (concentration of acid rain, mercury deposition)Impacts of fencing on wildlife populationsImpacts of arrays on bird populationsImpacts to surrounding ecosystem

*Solar Arrays

*Precipitation

*Fencing

*Heat Island?~164,300 panels

*Decommissioning & RestorationArray life estimated at 40 yrs., energy contract set for 20 yrs.End of life likely would result in newer technology being deployed for energy production.Decommissioning would require removal and disposal of all arrays, inverters, transformers, and fencingRestoration a restoration plan would be required prior to decommissioningNatural restoration since understory would be presentTree planting within understoryInvasive species management

Current Status70% cleared5 of 25 inverters set.10% of pilings installed2% of panels installed.*

Current Status Photos*

Current Status Photos*

Current Status Photos*

*Over all layourThis slide and others, as necessary, are for BP Solar to describe the project. At the very least, I think inserting the digital fly over video loop would be good for this presentation.This Slide is for LIPA to add material for opening remarks if desired.West BoundaryLimits future science, conflicts with BNL master plan, issues with WW I trenches, far from LIPA substationSouth BoundaryWithin Pine Barrens Core Preservation Area, far from LIPA substationDispersed open areasLimits future science, limits access to extensive utility system, far from LIPA substationRoof topsRoofs would need to be modified, energy routed through BNL internal grid or separate connections to LIPA grid, limits building upgrades

Largest impacts of this project are from cutting trees.Reiterate that the removal of trees as described in BP Solars planning documents, does not require significant grading after tree removal.Tree removal will also focus on removal of invasive species picture shown on next slide.Tree removal will force nesting birds to move to other forested areas of the Lab. T & E species will not be affected much since they are mostly associated with wetlands, same for reptiles and amphibians.Deer will be displaced,Small mammals may be temporarily displaced.Sunlight

Winter spacing of solar arrays are such that during the winter, sunlight will create shadows that will shade most of the area between arrays. This shading is at its maximum during the Winter solstice and gradually decreases to summer.Summer when the sun is at its highest during the summer spaces between arrays will receive full sunlight and only the area immediately below the arrays will be shaded. It is expected that plants that can tolerate full sunlight will flourish between arrays and will grade into plants that are shade tolerant under the arrays.

Precipitation

Due to impermiability of arrays, precipitation will concentrate along front drip-line of arrays. This will be the only area of concentration as native vegetation and permeable soils will likely alter vegetation regimes only minimally.Arrays will alter infiltration slightly from Native Forest canopy, creating areas of low moisture (directly below arrays) and areas of moderate (between arrays) to high While the power purchase agreement is for a 20 year period, the expected life of the arrays are roughly 40 years. Regardless of length of project, at the end the facility will have to be either upgraded, or Decommissioned and Restored.

Since the solar panels do not contain hazardous materials they will be removed and disposed of, pilings will be removed, cut, or driven into the ground. Area restored to native vegetation.In forty years the exact vegetation types will likely be negotiated.