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Low- and moderate-income (LMI) households face substantial barriers in accessing solar energy despite incentives at the local, state, and federal levels. Notwithstanding the rapid deployment of resources, there is still much to understand and address from a program design and implementation perspective to effectively realize an equitable energy transition. This qualitative study, which draws on interviews with policymakers, implementers, and LMI homeowners, provides novel insights into barriers and facilitators surrounding the inclusive adoption of solar energy. Our findings underscore the substantial differences and frequent misalignments in perspectives among these stakeholders. We find that both implementers and LMI homeowners encounter economic and administrative burdens, though the specific ways these factors hinder solar adoption differ between the groups. We leverage the viewpoints and experiences of policymakers, implementers, and LMI homeowners to guide evidence-based recommendations to overcome the many hurdles that actively impede equitable and inclusive solar adoption.

Background: While it is well documented that culture in hypoxic conditions produces superior outcomes, the mechanics of establishing such conditions within the embryo’s liquid environment is less clear. It is not uncommon for laboratories, while ‘culturing’ in low-oxygen, to equilibrate dishes in CO2 only environments prior to use, meaning embryos are exposed to high oxygen tension in their media even after placing into the hypoxic environment, but for how long is so far unclear. Aim: To assess the equilibration rate of oxygen within embryo culture media when exposed to hypoxic conditions. Method: A handheld blood gas analyser (EPOC system, ‘BGEM’ cartridges) was used to determine the pO2 of G1+ culture media after exposure to a reduced oxygen environment. Results: Culture media in atmospheric oxygen (with or without the presence of CO2) showed mean pO2 values of 150mmHg. Media fully equilibrated over 24 hours in 5% oxygen fell to approximately 70mmHg. This was well above the theoretically expected value but shown to be consistent across multiple measurements including various dish and incubator types. Initial equilibration to hypoxic conditions occurred relatively rapidly, with dishes undergoing 50% of the required oxygen reduction in only 30 minutes. Within 1.5 hours of exposure 5% O2, media achieved 83% of the required change, with full equilibration reached at approximately 2.5 hours. Pre-equilibration of dishes in 6% CO2 did not appear to affect the oxygen diffusion rate compared with non-equilibrated media. Oxygen exhibited similarly rapid diffusion into culture media when dishes equilibrated at 5% O2 were exposed to atmospheric conditions, with pO2 increasing by 1.46mmHg per minute. Conclusion: The diffusion rate of oxygen appears to be significantly faster than the more widely studied CO2, however, oxygen tension in media still requires greater than 2 hours to reach optimum levels, requiring us to consider oxygen in our equilibration practices.

Background: Maintaining optimal pH of culture media reduces environmental stressors on gametes and embryos, which has been shown to be critical in supporting embryo development. There are many options to determine pH but none are ideal for use in a laboratory setting. SignipHy™ is a system that monitors pH in real-time within the incubator environment without disturbing the incubator or exposing the media. Aim: To determine if SignipHy can provide an accurate representation of the dynamic pH in culture media across a range of environmental conditions. Method: pH of G1+ under Ovoil in a 5-well dish was measured using a blood gas analyser at regular intervals under multiple experimental conditions. Statistical analyses used repeated measures ANOVA, Pearson’s Correlation and Linear regression. Results: pH of media undergoing initial equilibration was found to decrease more rapidly in culture dishes (ΔpH 0.228/hr) than SignipHy cuvettes (ΔpH 0.160/hr) over a 6 hour period (p=0.0005). Full equilibration was achieved in the culture dishes after 4 hours, while the SignipHy cuvettes stabilised after 6 hours. When fully equilibrated dishes were exposed to 4% CO2, pH in the culture dishes increased more rapidly (ΔpH 0.098/hr) than SignipHy cuvettes (ΔpH 0.060/hr). Similarly, equilibrated media exposed to 2% CO2 showed an increase of pH in culture dishes of 0.171/hr compared with SignipHy cuvettes at 0.150/hr. Unsurprisingly when media in a culture dish without oil was exposed to a humified CO2 incubator the pH shift was rapid (ΔpH 0.258/hr). Laboratories should be conscious of rapid pH shifts in culture media without oil. Which can be optimal when needing to equilibrate media quickly, but of concern when handling dishes. Conclusion: SignipHy was found to be a viable representation of pH under multiple experimental conditions, however, the rate of change was found to be slower compared to culture dishes.

Background: Oil overlay in IVF culture media is essential in the maintenance of pH and prevention of evaporation. The recent proliferation of “Heavy oil” raises questions of how oil density and viscosity affect CO2 diffusion into and out of culture media. Aim: To compare the effects of “Heavy oil” versus standard oil on pH stability in embryo culture dishes. Method: Density (g/ml) readings of each oil (Ovoil, Ovoil Heavy and LifeGuard) were obtained in triplicate using a volumetric flask and analytical balance in both refrigerated (4[Formula: see text]C) and warmed state (37[Formula: see text]C). Viscosity testing was performed externally by Intertek laboratory. pH was measured at regular intervals using a blood gas analyser (EPOC system) in culture dishes under standard and ‘Heavy’ oil overlays. Results: Density measurements showed Ovoil Heavy to be the least dense (0.8227g/ml) followed by Ovoil (0.8476g/ml), with LifeGuard the most dense at 0.8640g/ml. There was a significant difference (p