Agenda - Council Work Session - 04/11/2023

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capacity factor (4.81 acres per MW) to calculate the generating potential in MW. Our capacity factor is calculated based on typical equipment specifications and a ground coverage ratio of 30%. Capacity factor will vary depending on equipment, arrangement of panels and barriers/obstructions to equipment. The resulting number represents the nameplate capacity which is the maximum or rated capacity for typical installed equipment. Buffer generation potential represents the solar capacity of the non -cap areas within the LMA. While the "buffer," as it is commonly called, does not present the same unique construction challenges as the cap area, we found a wide variety of natural and human -made features which can reduce the buildable area within the buffer. Using our GIS tool, we identified data sets for wetlands, open water, scientific and natural areas, forest (conifer, deciduous and mixed), and developed areas (low, medium, and high density). We identified the acreage for each of these natural and human -made features for each site, subtracted those acres from the total buffer acreage and calculated the buildable acres for each buffer. To calculate the generating potential for each buffer we divided each buildable area in acres by a standard capacity factor to calculate the generating potential in MW. The standard capacity factor for solar development is 4.81 acres per MW. The resulting number represents the nameplate capacity for the landfill buffer. Site solar generation potential represents the combined solar capacity of the buffer and the cap to calculate the total nameplate capacity of the landfill site. This is an important criterion because it gives a more complete picture of the generating potential of a site. It is important to identify both the cap and buffer capacity because each has solar potential, and each may be preferred for solar development for different reasons. We received feedback from developers suggesting the cap area has been more likely to be developed in other states where solar had been developed on landfill sites. This may be related to a lack of buffer land or the way in which solar development incentives were crafted. Advantages of solar development on the cap include large, relatively flat surfaces with little or no large vegetation to remove or wetlands/open water to work around or requiring a permit. Disadvantages include operational features which need to be avoided: gas extraction wells, passive gas vents, stormwater management features and leachate cleanout access. Another disadvantage is increased construction costs associated with the use of ballasted racking systems in order to avoid penetrating the cap. The advantages to the buffer include good quantity of available land and the ability to use lower cost conventional construction equipment and techniques. Disadvantages associated with the buffer include natural landscape that will have to be affected (wetlands, forests, and other vegetation), the existing grade may not be conducive to solar development and human development within the LMA (buildings, roads, and residents). In any case, calculating the site solar generation potential provides a sense of the scale of the development opportunity of these sites. Specific challenges with cap and/or buffer development at any site may be overcome with greater scale. Distance to the nearest electrical substation is an important criterion because of the significant cost of connecting solar generation to the existing transmission or distribution grid. We chose distance to a substation because a substation represents a logical place to connect to an existing transmission or distribution network. We identified existing, publicly available data regarding the location of existing electrical substations and used our GIS system to measure the distance in miles from the closed landfill sites to the nearest substation. WO