Standardized metrics to quantify solar energy-land relationships: A global systematic review

Ground-mounted solar energy installations, including photovoltaics (PV) and concentrating solar power (CSP), can have significant environmental, ecological, and sociocultural effects via land-use and land-cover change (LULCC). Research in disciplines ranging from engineering to environmental policy seeks to quantify solar energy-land (SE-land) interactions to better understand the comprehensive impacts of solar energy installations on society. However, increasing evidence shows that scholars across research disciplines employ disparate metrics to quantify SE-land interactions. While solar energy deployment helps to achieve progress toward sustainable development goals (SDG 7- affordable and clean energy), the inconsistent use of metrics to describe SE-land interactions may inhibit the understanding of the total environmental and ecological impacts of solar energy installations, potentially causing barriers to achieve concurrent SDG's such as life on land (SDG 15). We systematically reviewed 608 sources on SE-land relationships globally to identify and assess the most frequent metric terms and units used in published studies. In total, we identified 51 unique metric terms and 34 different units of measure describing SE-land relationships across 18 countries of author origin. We organized these findings into three distinct metric categories: (1) capacity-based (i.e., nominal), (2) generation-based, and (3) human population-based. We used the most frequently reported terms and units in each category to inform a standardized suite of metrics, which are: land-use efficiency (W/m2), annual and lifetime land transformation (m2/Wh), and solar footprint (m2/capita). This framework can facilitate greater consistency in the reporting of SE-land metrics and improved capacity for comparison and aggregations of trends, including SE-land modeling projections. Our study addresses the need for standardization while acknowledging the role for future methodological advancements. The results of our study may help guide scholars toward a common vernacular and application of metrics to inform decisions about solar energy development

Leveraging the Health and Retirement Study To Advance Palliative Care Research

Background: The critical need to expand and develop the palliative care evidence base was recently highlighted by the Journal of Palliative Medicine's series of articles describing the Research Priorities in Geriatric Palliative Care. The Health and Retirement Study (HRS) is uniquely positioned to address many priority areas of palliative care research. This nationally representative, ongoing, longitudinal study collects detailed survey data every 2 years, including demographics, health and functional characteristics, information on family and caregivers, and personal finances, and also conducts a proxy interview after each subject's death. The HRS can also be linked with Medicare claims data and many other data sources, e.g., U.S. Census, Dartmouth Atlas of Health Care. Setting: While the HRS offers innumerable research opportunities, these data are complex and limitations do exist. Therefore, we assembled an interdisciplinary group of investigators using the HRS for palliative care research to identify the key palliative care research gaps that may be amenable to study within the HRS and the strengths and weaknesses of the HRS for each of these topic areas. Conclusion: In this article we present the work of this group as a potential roadmap for investigators contemplating the use of HRS data for palliative care research.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140117/1/jpm.2013.0648.pd

Floating solar panels on reservoirs impact phytoplankton populations: a modelling experiment

Floating solar photovoltaic (FPV) deployments are increasing globally as the switch to renewable energy intensifies, representing a considerable water surface transformation. FPV installations can potentially impact aquatic ecosystem function, either positively or negatively. However, these impacts are poorly resolved given the challenges of collecting empirical data for field or modelling experiments. In particular, there is limited evidence on the response of phytoplankton to changes in water body thermal dynamics and light climate with FPV. Given the importance of understanding phytoplankton biomass and species composition for managing ecosystem services, we use an uncertainty estimation approach to simulate the effect of FPV coverage and array siting location on a UK reservoir. FPV coverage was modified in 10% increments from a baseline with 0% coverage to 100% coverage for three different FPV array siting locations based on reservoir circulation patterns. Results showed that FPV coverage significantly impacted thermal properties, resulting in highly variable impacts on phytoplankton biomass and species composition. The impacts on phytoplankton were often dependent on array siting location as well as surface coverage. Changes to phytoplankton species composition were offset by the decrease in phytoplankton biomass associated with increasing FPV coverage. We identified that similar phytoplankton biomass reductions could be achieved with less FPV coverage by deploying the FPV array on the water body's faster-flowing area than the central or slower flowing areas. The difference in response dependent on siting location could be used to tailor phytoplankton management in water bodies. Simulation of water body-FPV interactions efficiently using an uncertainty approach is an essential tool to rapidly develop understanding and ultimately inform FPV developers and water body managers looking to minimise negative impacts and maximise co-benefits

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

Background: The EMPA KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population. Methods: EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110. Findings: Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5–2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62–0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16–1·59), representing a 50% (42–58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1). Interpretation: In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease. Funding: Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council

Land Sparing, Environmental, and Hydrological Impacts of Floating Solar Photovoltaic Energy Installations

Rapid, global development of renewable energy, especially solar energy, is increasingly playing a pivotal role in mitigating climate change and meeting both national and global decarbonization goals. While transitioning from fossil fuels to renewable energy is necessary to address climate change and adhere to international climate accords, solar energy can have impacts—both positive and negative—on the environment and require large amounts of land. As such, novel solar energy applications, such as floating solar energy photovoltaics (FPV), have been gaining traction globally as the technology increases accessibility to solar energy to land-limited populations and also may provide non-energy benefits to the host water body. However, FPV technology is still relatively new, with little understanding of the technology on environmental and hydrological conditions. Additionally, there is a dearth of understanding towards how FPV installations relate to ground-mounted PV technologies in terms of performance and land use. The main goal of this dissertation is ultimately to explore the land use implications of solar energy technologies and, more specifically, investigate the environmental and hydrological implications of floating solar photovoltaics. While this dissertation mainly focuses on the hydrological, environmental, and land-use impacts associated with floating solar photovoltaic energy installations, it also evaluates the impact of ground-mounted solar energy-land-use interactions to form a comprehensive understanding of the interplay between solar energy and the environment. As such, this research consists of four portions: 1. Using a systematic literature review on solar energy-land use metrics to propose a standardized suite of metrics for communicating solar energy-land interactions, 2. Evaluating the land sparing benefits of floating solar energy installations and propose metrics for communicating the spatial footprint of FPVs, 3. Investigating the impacts of FPV on continuous water temperature and dissolved oxygen dynamics at multiple locations across the United States, 4. Investigating the impacts of FPV on major water quality parameters and algae growth dynamics at multiple FPV locations across unique climatic zones. In the first chapter, a systematic literature review is conducted that evaluates the current state of solar energy-land use metrics across disciplines. Specifically, this chapter focuses on the disconnect between the metric term and associated units across studies and how this disconnect leads to the inaccurate dissemination of findings across studies. This review quantifies metric term and unit usage and uses these findings to propose standardized metrics in three distinct categories: capacity-based, generation-based, and population-based solar energy-land use metrics. By doing so, the goal of this chapter is to minimize the use of an unnecessary number of unique metrics to define identical parameters and, ultimately, aid in the accurate dissemination of findings across disciplines. In the second chapter, an evaluation of the land sparing aspects of floating solar installations along with quantifying the water surface use efficiency and water surface transformation of four FPV installations across the United States is conducted. Metrics for both generation-based and capacity-based surface use by FPV installations is proposed following similar naming mechanisms identified in chapter 1 for ground-mounted installations. The two metrics are then calculated for the four sites in this study and compared to ground-mounted installations on a per-unit of PV area basis. The results of this study indicate that the four FPVs in this study are more efficient on a per m2 of installation basis in both generation and capacity. While these findings demonstrate the technical benefits of FPVs, the chapter also provides a path for future comparative studies between FPV and other renewable energy technologies. In chapter three, a one-year field study is conducted that continuously monitors water temperature and dissolved oxygen at three FPV locations across the United States. The study compares water column temperature at multiple depths and near-surface dissolved oxygen below the FPV compared to open water locations of the same host water body. The results of this study indicate that high-coverage FPV installations compared to the water surface area can have significantly lower temperatures beneath the FPV installation than in the open water body. Dissolved oxygen is also found to be less beneath all FPV installations. Additionally, this study identifies ways in which FPVs shift the temperature range of the water column on a diel basis and shifts warming patterns towards later in the day. These findings can better inform future modeling efforts of FPV installations, specifically on shallow bodies of water, and help elucidate the impact FPV could have at helping mitigate the impacts of warming urban waterways due to climate change and urbanization. In the final chapter, a seasonal spot sampling field campaign is conducted that evaluates water quality parameters and algal growth dynamics below FPV installations compared to open water portions of the host water body. Specifically, temperature, dissolved oxygen, pH, phycocyanin, chlorophyll-a, and conductivity measurements were collected via handheld sonde over the course of four seasons from 2021-2022. Each season consisted of four days of twice-daily campaigns, one in the morning and one in the late afternoon. The findings from this study indicate that FPVs may not have a significant impact on algal growth within the host water body and further validate findings from chapter three on dissolved oxygen concentrations being lower beneath the FPV. The findings of this chapter demonstrate the need for further, continuous monitoring of water quality parameters at FPV installations and greater access to pre-FPV construction data in order to fully grasp trends that may be occurring as a response to FPV deployments

“It Just Consumes Your Life”

Little is known about the quality of life (QoL) for informal caregivers of disabled older adults aged 65+ with diverse backgrounds. Forty-two caregivers were interviewed in English and Cantonese about their caregiving experiences, their recollections of QoL over time, and the factors influencing their appraisals. Overall, 52% of caregivers experienced a decline in QoL. Factors associated with decreased QoL were less time for self, competing financial demands, and the physical and emotional impact of the patient's illness. Factors associated with no change in QoL were minimal caregiving responsibilities, a sense of filial duty, and QoL being consistently poor over time. Factors associated with improved QoL were perceived rewards in caregiving, receiving institutional help, and increased experience. Chinese caregivers were more likely to cite filial duty as their motivator for continued caregiving than were Caucasian caregivers. In conclusion, informal caregivers take on a huge burden in enabling older adults to age in the community. These caregivers need more support in maintaining their QoL

Comments on: Land use for United States power generation: A critical review of existing metrics with suggestions for going forward (Renewable and Sustainable Energy Reviews 2021; 143: 110911)

Highlights • Wachs and Engel (2021) report outcomes describing energy-land relationships. • The methodological approaches in Wachs and Engel (2021) are absent. • Results presented in Wachs and Engel (2021) should be considered with caution. • Literature reviews and analyses on land-energy relationships should be rigorous. • Fair and open standardization of metrics for land-energy relationships are needed

Standardized metrics to quantify solar energy-land relationships:A global systematic review

Ground-mounted solar energy installations, including photovoltaics (PV) and concentrating solar power (CSP), can have significant environmental, ecological, and sociocultural effects via land-use and land-cover change (LULCC). Research in disciplines ranging from engineering to environmental policy seeks to quantify solar energy-land (SE-land) interactions to better understand the comprehensive impacts of solar energy installations on society. However, increasing evidence shows that scholars across research disciplines employ disparate metrics to quantify SE-land interactions. While solar energy deployment helps to achieve progress toward sustainable development goals (SDG 7- affordable and clean energy), the inconsistent use of metrics to describe SE-land interactions may inhibit the understanding of the total environmental and ecological impacts of solar energy installations, potentially causing barriers to achieve concurrent SDG's such as life on land (SDG 15). We systematically reviewed 608 sources on SE-land relationships globally to identify and assess the most frequent metric terms and units used in published studies. In total, we identified 51 unique metric terms and 34 different units of measure describing SE-land relationships across 18 countries of author origin. We organized these findings into three distinct metric categories: (1) capacity-based (i.e., nominal), (2) generation-based, and (3) human population-based. We used the most frequently reported terms and units in each category to inform a standardized suite of metrics, which are: land-use efficiency (W/m2), annual and lifetime land transformation (m2/Wh), and solar footprint (m2/capita). This framework can facilitate greater consistency in the reporting of SE-land metrics and improved capacity for comparison and aggregations of trends, including SE-land modeling projections. Our study addresses the need for standardization while acknowledging the role for future methodological advancements. The results of our study may help guide scholars toward a common vernacular and application of metrics to inform decisions about solar energy development