Ilke Celik

A technoeconomic analysis of perovskite solar module manufacturing with low-cost materials and techniques

After rapid progress in the past few years, emerging solar cells based on metal halide perovskites have become a potential candidate to rival and even outperform crystalline silicon photovoltaics (PV) in the marketplace. With high material utilization, easy manufacturing processes, and high power conversion efficiencies >20%, many experts anticipate that perovskite solar cells (PSCs) will be one of the cheapest PV technologies in the future. Here we evaluate the economic potential of PSCs by developing a bottom-up cost model for perovskite PV modules fabricated using feasible low-cost materials and processes. We calculate the direct manufacturing cost (

Environmental analysis of perovskites and other relevant solar cell technologies in a tandem configuration

31.7 per m2) and the minimum sustainable price (MSP,

Environmental Impacts from Photovoltaic Solar Cells Made with Single Walled Carbon Nanotubes

0.41 per Wp) for a standard perovskite module manufactured in the United States. Such modules, operating at 16% photoconversion efficiency in a 30-year, unsubsidized, utility-level power plant, would produce electricity at levelized cost of energy (LCOE) values ranging from 4.93 to 7.90 ¢ per kW per h. We discuss limitations in comparing calculated MSPs to actual market prices, determine the effect of module lifetime, examine the effects of alternative materials and constructions, and indicate avenues to further reduce the MSP and LCOE values. The analysis shows that PSCs can emerge as a cost leader in PV power generation if critical remaining issues can be resolved.

Life cycle toxicity analysis of emerging PV cells

Future high performance PV devices are expected to be tandem cells consisting of a low bandgap bottom cell and a high bandgap top cell. In this study, we developed a cradle-to-end of use life cycle assessment model to evaluate the environmental impacts, primary energy demand (PED), and energy payback time (EPBT) of four integrated two-terminal tandem solar cells composed of either Si bottom and lead-based perovskite (PKPb) top cells (Si/PKPb), copper indium gallium selenide (CIGS) and PKPb (CIGS/PKPb), copper zinc tin selenide (CZTS) and PKPb (CZTS/PKPb), or tin-lead based perovskite (PKSn,Pb) and PKPb (PKSn,Pb/PKPb). Environmental impacts from single junction Si solar cells were used as a reference point to interpret the results. We found that the environmental impacts for a 1 m2 area of a cell were largely determined by the bottom cell impacts and ranged from 50% (CZTS/PKPb) to 120% of those of a Si cell. The ITO layer used in Si/PKPb, CZTS/PKPb, and PKSn,Pb/PKPb is the most impactful after the Si and CIGS absorbers, and contributed up to 70% (in PKSn,Pb/PKPb) of the total impacts for these tandem PVs. Manufacturing a single two-terminal device was found to be a more environmentally friendly option than manufacturing two constituent single-junction cells and can reduce the environmental impacts by 30% due to the exclusion of extra glass, encapsulation, front contact and back contact layers. PED analysis indicated that PKSn,Pb/PKPb manufacturing has the least energy-intensive processing, and the EPBTs of Si/PKPb, CIGS/PKPb, CZTS/PKPb, and PKSn,Pb/PKPb tandems were found to be ∼13, ∼7, ∼2, and ∼1 months, respectively. On an impacts per kW h of Si basis the environmental impacts of all the devices were much higher (up to ∼10 times). These results can be attributed to the low photoconversion efficiency (PCE) and short lifetime that were assumed. While PKSn,Pb/PKPb has higher impacts than Si based on current low PCE (21%) and short lifetime (5 years) assumptions, it can outperform Si if its lifetime and PCE reach 16 years and 30%, respectively. Among the configurations considered, the PKSn,Pb/PKPb structure has the potential to be the most environmentally friendly technology.

Development of a new online learning module on solar energy sustainability

An ex-ante life cycle inventory was developed for single walled carbon nanotube (SWCNT) PV cells, including a laboratory-made 1% efficient device and an aspirational 28% efficient four-cell tandem device. The environmental impact of unit energy generation from the mono-Si PV technology was used as a reference point. Compared to monocrystalline Si (mono-Si), the environmental impacts from 1% SWCNT was ∼18 times higher due mainly to the short lifetime of three years. However, even with the same short lifetime, the 28% cell had lower environmental impacts than mono-Si. The effects of lifetime and efficiency on the environmental impacts were further examined. This analysis showed that if the SWCNT device efficiency had the same value as the best efficiency of the material under comparison, to match the total normalized impacts of the mono- and poly-Si, CIGS, CdTe, and a-Si devices, the SWCNT devices would need a lifetime of 2.8, 3.5, 5.3, 5.1, and 10.8 years, respectively. It was also found that if the SWCNT PV has an efficiency of 4.5% or higher, its energy payback time would be lower than other existing and emerging PV technologies. The major impacts of SWCNT PV came from the cells materials synthesis.

Ecological network analysis of growing tomatoes in an urban rooftop greenhouse

The rapid improvement in the performance of photovoltaic (PV) solar cells has resulted in an overall reduction in the environmental impacts. Simultaneously, the source of the impacts has shifted from the processing energy to the materials themselves. We analyzed the potential toxicity of new materials to provide insight into material and technology selection. We evaluated metal releases to different ecological compartments and estimated human and ecological toxicity potentials using the life cycle assessment (LCA) approach. We observed that leaching of metals to the environment during the use or end-of-life phase can significantly increase the toxicity.

Diversity analysis of water sources, uses, and flows from source to use in the USA

College curricula in the U.S. are now more intentionally incorporating topics related to infrastructure engineering, energy, and sustainability. While these three topics are typically developed and taught independently by faculty from different backgrounds and departments, curricula that integrate these three concepts are needed to train the students to more adequately tackle current and future energy challenges. In this paper, we describe the development and content of a new online curriculum that integrates infrastructure, energy, and sustainability concepts. This new online learning module focuses on both lower order skills (knowledge of basic PV concepts) and higher order skills (analysis and design recommendations for PV cells).

Management of rainwater harvesting and its impact on the health of people in the Middle East: case study from Yatta town, Palestine

Urban agriculture has emerged as an alternative to conventional rural agriculture seeking to foster a sustainable circular economy in cities. When considering the feasibility of urban agriculture and planning for the future of food production and energy, it is important to understand the relationships between energy flows throughout the system, identify their strengths and weaknesses, and make suggestions to optimize the system. To address this need, we analyzed the energy flows for growing tomatoes at a rooftop greenhouse (RTG). We used life cycle assessment (LCA) to identify the flows within the supply chain. We further analyzed these flows using ecological network analysis (ENA), which allowed a comparison of the industrial system to natural systems. Going beyond LCA, ENA also allowed us to focus more on the relationships between components. Similar to existing ENA studies on urban metabolism, our results showed that the RTG does not mimic the perfect pyramidal structure found in natural ecosystems due to the systems dependency on fossil fuels throughout the supply chain and each industrys significant impact on wasted energy. However, it was discovered that the RTG has strong foundational relationships in its industries, demonstrating overall positive utility; this foundation can be improved by using more renewable energy and increasing the recycling rates throughout the supply chain, which will in turn improve the hierarchy of energy flows and overall energy consumption performance of the system.

Life Cycle Assessment (LCA) of perovskite PV cells projected from lab to fab

Diversifying a system can reduce risk from- and increase resilience to perturbation. For this reason, the concept of diversity has been used in many different fields but its use in analyzing engineering infrastructure has been limited. In particular, the diversity of water sources and uses and the diversity of how sources are connected to uses (flow) have never been analyzed. In addition, the relationships between diversity and economic efficiency of water systems remain uncertain. In this study, we addressed these topics by conceptualizing and quantifying water source, use, and flow diversity in the USA. Water source and water use data were collected from the US Geological Survey for 2000, 2005, and 2010. Diversity was calculated with the Shannon Weaver Index. The overall mean water use diversity by state was 0.79 ± 0.31 (N = 150) and increased from 0.63 ± 0.31 in 2000 to 0.89 ± 0.28 by 2010, reflecting overall decreases in high-use categories, like thermonuclear power, and relative increases in already low domestic use. In contrast, source diversity showed no change over time, with an overall state mean of 0.82 ± 0.28 (N = 150) but varying between states largely due to differences in geographic and climatic factors influencing regional water sources. Water flow diversity also showed no change over time, averaging 1.00 ± 0.43 (N = 150), higher than both source and use diversity. The mean water use efficiency for all states over the study period was 52 ± 60 

Energy Payback Time (EPBT) and Energy Return on Energy Invested (EROI) of Perovskite Tandem Photovoltaic Solar Cells

/m3 of water and was positively and strongly related to both source and use diversity. Thus, the USA water system diversity is sensitive to factors logically expected to influence both source and use, and directly affects water use efficiency.