درونسازی اثرات استفاده از زمین برای تجزیه و تحلیل هزینه های چرخه عمر سیستم های انرژی: مورد اجرای فتوولتائیک کالیفرنیا
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|23413||2014||7 صفحه PDF||سفارش دهید||5762 کلمه|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Applied Energy, Volume 116, 1 March 2014, Pages 253–259
Solar photovoltaic (PV) is a rapidly growing electricity generation technology. The increasing penetration of this technology is facilitated by incentives and public policy support that are being offered by various jurisdictions. There are various options for installing photovoltaic systems, rooftop and ground mounted systems being the two common options. The choice between these options has been complicated by the tradeoffs between cost and land use impacts. In this paper we develop a framework that can be used to highlight and quantify the tradeoffs between costs and land using life cycle costs (LCC), life cycle land use footprints (LUF), and consequent land use impacts (LUI) across various options of implementing PV systems. We demonstrate the application of the framework using a hypothetical case study of implementing various options of PV systems in California. The results indicate that at 14.2 ¢/kWh, the utility-scale ground mounted option has the lowest LCC compared to residential and commercial rooftop mounted options. However, the utility-scale option has the highest land use footprint and land use impacts. The monitory value of the land use impacts from implementing utility scale ground mounted systems depends primarily on the type of associated ecosystems and the value people place on them. For the rooftop option in this case study to be preferred to the ground mounted option, the value of land use impacts would have to increase significantly.
Photovoltaic (PV) systems are penetrating electricity markets at a rapid rate in several regions around the world. For example, between 2009 and 2010 the installed PV capacity increased by 131% globally and by 84% in the US . California accounts for 47% of installed PV capacity in the US. In 2010 alone, 225 MW of PV was installed in California increasing its cumulative installed capacity to 1.02 GW (1.4% of California’s electricity generation capacity in 2010) . Increasing electricity demand, federal and state policies such as rebate programs, investment tax credits, net metering, favorable interconnection policies (operating, metering and interconnecting requirements that a generator has to meet to connect to a utilities distribution system), and rate structures have been key to the penetration of PV systems in California  and . There are various options for installing photovoltaic systems, rooftop and ground mounted systems being two common options. The California government is providing incentives for both options; however, the investment decision between these options is complicated by tradeoffs between cost and land use impact. For example, incentives for rooftop PV system installations with a target of 3 GW operating in California by 2016 . At the same time, the Bureau of Land Management (BLM) has allocated 619 million square meters of public land in the desert regions of Southern California for the development of solar energy systems. This has been critical to the deployment of utility scale ground mounted systems . However, there has been opposition to the use of public lands for these developments due to the impacts on ecological and cultural resources in these desert ecosystems  and . The objective of this paper is to develop and demonstrate a framework that can be used to highlight and quantify the tradeoffs between costs and land impacts using life cycle costs (LCC), life cycle land use footprints (LUF), and consequent land use impacts (LUI) for various options of implementing PV systems. LCC is a tool that can be used to estimate the cradle to grave costs associated with a product or a service . LCC can also be used to compare a series of product or service alternatives and generally accounts for all costs arising from initial capital costs, recurring costs such as annual maintenance, non-recurring costs that occur irregularly such as replacement and repairs of system parts, end of life decommissioning and disposal costs as well as the time value of money , ,  and . Land use impacts of PV system implementations can be estimated using the total area required, the time of occupation of land, and the change in the quality of land for a particular activity (e.g., per kWh) . The change in quality of land can be defined by how well land performs its “functions”. These functions include (but are not limited to) erosion resistance, filtering, buffering capacity of the soil, ground water protection, buffering surface water (flood regulation), protection from impacts such as noise, biomass production, decomposition of organic matter, habitat for human and non-human life, and landscape quality (for example: scenic views, culturally important sites ). Land use impacts from PV systems may result from site modifications such as clearing of vegetation, grading of land, redirecting water flow, fencing, creating access roads and pouring concrete pads to mount electrical equipment  and . Impacts of such anthropogenic modifications in desert lands have been discussed in the literature by , , , ,  and . The impact of solar energy development on the desert ecosystem particularly endangered species such as the desert tortoise have begun to raise concerns among California residents . California’s deserts also have archeological and ethnological sites such as burial sites, trails that link resources to cultural sites, geoglyphs, rock art, and artifacts of early human settlement . The potential deterioration of these sites from development of solar energy systems has also raised concerns . Therefore, incorporating the value of land use impacts into the decision making process can provide a better understanding of the total cost of PV systems on society. Ascribing a monitory value to the various qualities of land and the impact of their loss has been undertaken in environmental economic studies, using various methods. These methods include contingent valuation (willingness-to-pay) , ,  and , travel cost methods  and , choice experiments , hedonic pricing  and , and value transfer methods . Several studies have examined the life cycle costs of various options of implementing PV , , ,  and . However, no study was found that makes a comparative assessment from a systems perspective (including transmission line losses and costs) while internalizing societal costs that occur from land use impacts. Furthermore, studies that have valued ecosystem services, as seen above, focus on the methods and assessment of ecosystem services and to date have not explored the implications of internalizing these impacts in a LCC. In addition, no study was identified that employed the valuation of ecosystem services to the total life cycle cost of various options for implementing PV systems.
نتیجه گیری انگلیسی
This paper presents a framework that can be used to systematically assess the tradeoffs between the life cycle costs, land use footprints, and land use impacts across the various options for implementing PV systems. The framework provided in this paper can assist stakeholders in understanding the tradeoffs between costs and externalities. Regulators such as county representatives can use the framework to determine or redesign land rents so that the value of land use impacts and other social expenditures can be compensated. Utilities can apply the framework to determine the return on investment and help in determining the competitiveness of these options against other competing options. The total life cycle cost of the PV system can be compared against the price received for the electricity delivered. After understanding the return on investment, and having to comply with the RPS requirements, utilities can develop a business plan. One limitation of this analysis is that we did not fully explore the implications and options related to intermittency and variability of PV systems. PV systems can only generate electricity during daylight hours. They also vary in the amount of electricity generated, for example, more during sunny periods and less during cloud cover and shadows. During periods when the electricity production is higher than the demand, excess electricity can be stored in storage systems or sold to the grid. Batteries can increase the initial investment cost of residential PV systems by roughly 10% and total life cycle cost by 30–33%  and . Currently, many grid tied systems have the option of selling excess generation back to the grid and buying electricity from the grid when the PV system is not producing. The returns or savings depend on how much of the buildings electricity demand the PV system is able to satisfy, particularly during peak hours, the size of the PV system, and the rates that are offered by the purchasing utilities ,  and . All of these options could be explored further in future work. As an initial framework, this study can be developed further by extending the boundaries of investigation to include other parameters particularly other external costs. The external costs considered in this paper are limited to land use impacts; the loss of naturalness and loss of potential carbon sink. However, other environmental impacts (carbon footprint, impact on water), impacts on the economy (price of land, housing, green jobs, transactional costs for residential and commercial projects), alternate use of land (agriculture), and unintended consequences (loss of revenue from hidden taxes in electricity bills, and taxes paid by utilities) should also be included. Additionally, this study considered the negative impacts of the loss of potential carbon sink. However, it did not consider the potential carbon displacement potential of PV systems where electricity generation is dominated by fossil fuel based technologies. These could also be explored. Previous studies have attempted to measure the value of ecosystem services but no consensus about the methods and values have been achieved. In addition, specific methods such as contingent valuation also lack consensus. During our study we found that using the total willingness to pay per household per year gives higher values for land use impacts than using total willingness to pay per meter square per year by the residents of California. Therefore depending on the approach taken the value of land use impacts vary. We propose future work to standardize methods of including monetary values of ecosystems and ecosystem into life cycle frameworks.