• Energy Research

AbstractPredicting radiative forcing due to Antarctic stratospheric ozone recovery requires detecting changes in the ozone vertical distribution. In this endeavor, the Limb Profiler of the Ozone Mapping and Profiler Suite (OMPS-LP), aboard the Suomi NPP satellite, has played a key role providing ozone profiles over Antarctica since 2011. Here, we compare ozone profiles derived from OMPS-LP data (version 2.5 algorithm) with balloon-borne ozonesondes launched from 8 Antarctic stations over the period 2012–2020. Comparisons focus on the layer from 12.5 to 27.5 km and include ozone profiles retrieved during the Sudden Stratospheric Warming (SSW) event registered in Spring 2019. We found that, over the period December-January–February-March, the root mean square error (RMSE) tends to be larger (about 20%) in the lower stratosphere (12.5–17.5 km) and smaller (about 10%) within higher layers (17.5–27.5 km). During the ozone hole season (September–October–November), RMSE values rise up to 40% within the layer from 12.5 to 22 km. Nevertheless, relative to balloon-borne measurements, the mean bias error of OMPS-derived Antarctic ozone profiles is generally lower than 0.3 ppmv, regardless of the season.

In photovoltaic power ratings, a single solar spectrum, AM1.5, is the de facto standard for record laboratory efficiencies, commercial module specifications, and performance ratios of solar power plants. More detailed energy analysis that accounts for local spectral irradiance, along with temperature and broadband irradiance, reduces forecast errors to expand the grid utility of solar energy. Here, ground-level measurements of spectral irradiance collected worldwide have been pooled to provide a sampling of geographic, seasonal, and diurnal variation. Applied to nine solar cell types, the resulting divergence in solar cell efficiencies illustrates that a single spectrum is insufficient for comparisons of cells with different spectral responses. Cells with two or more junctions tend to have efficiencies below that under the standard spectrum. Silicon exhibits the least spectral sensitivity: relative weekly site variation ranges from 1% in Lima, Peru to 14% in Edmonton, Canada.

Soils have the capacity to provide a wide range of soil functions that can help address socio-environmental challenges, such as climate change and biodiversity loss. Here, we apply the Functional Land Management framework aimed at optimally balancing supply and demand of soil functions at a landscape-scale to drained coastal peat (Histosols) in Friesland, The Netherlands. We focus on the supply side by assessing the capacity of grassland peat soils with different topsoil types to provide five soil functions: climate regulation, habitat provision, nutrient cycling, water storage, and primary productivity. A field campaign was conducted in March 2022 to collect data on soil, water, vegetation, and management from 30 grasslands mapped as peat on the national soil map (Basisregistratie Ondergrond). Results revealed significant differences in above and belowground field conditions between peat with different topsoil types. Peat soils with a mineral cover are predominantly used as grasslands for dairy farming, with a clear differentiation in functioning between fields managed by organic and conventional farmers. Peat soils without a mineral cover are generally owned by nature organizations and managed as semi-natural grasslands aimed at optimizing aboveground habitat provision. Our results show that conventional agricultural management, including deep drainage and high fertilizer inputs, results in moderate to high nutrient cycling and primary productivity, along with low climate regulation, water storage and habitat provision. Extensification results in a decrease in primary productivity and nutrient cycling along with a strong increase in climate regulation, water storage, and habitat provision. To optimize landscape-scale provision of soil functions, we recommend promoting soil multifunctionality while maintaining moderately high yields on peat with a mineral cover. To benefit from the unique and yet unmet potential of peat soil for climate regulation and water storage, we recommend tailoring management of peat soils without a mineral cover to fully restore natural peatlands.

Abstract Satellites have consistently pointed to the Altiplano of the Atacama Desert as the place on Earth where the world’s highest surface irradiance occurs. This region, near the Tropic of Capricorn, is characterized by its high elevation, prevalent cloudless conditions, and relatively low concentrations of ozone, aerosols, and precipitable water. Aimed at studying the variability of the surface solar irradiance and detecting atmospheric composition changes in the Altiplano, an atmospheric observatory was set up in 2016 at the northwestern border of the Chajnantor Plateau (5,148 m MSL, 22.95°S, 67.78°W, Chile). Here, we report on the first 5 years of measurements at this observatory that establish the Altiplano as the region that receives the highest-known irradiation on Earth and illuminate the unique features of surface solar extremes at high-altitude locations. We found that the global horizontal shortwave (SW) irradiance on the plateau is on average 308 W m−2 (equivalent to an annual irradiation of 2.7 MWh m−2 yr−1, the highest worldwide). We also found that forward scattering by broken clouds often leads to intense bursts of SW irradiance; a record of 2,177 W m−2 was measured, equivalent to the extraterrestrial SW irradiance expected at approximately 0.79 astronomical units (AU) from the Sun. These cloud-driven surface solar extremes occur on the Chajnantor Plateau at a frequency, intensity, and duration not previously seen anywhere in the world, making the site an ideal location for studying the response of photovoltaic (PV) power plants to periods of enhanced SW variability.

In this paper, we assess the sustainability of rural electrification programs in Ecuador, paying special attention to programs targeting small indigenous communities in the Amazon basin. Our assessment considers four dimensions of sustainability (institutional, economic, environmental, and socio-cultural) and is based on an exhaustive qualitative document analysis, complemented by semi-structured expert interviews. We found that disruptive changes have affected the electrification policies in Ecuador during decades of avoiding the development of strengthened institutions. Despite this major drawback, we found that there is a consensus on granting access to energy for all. This partially explains the national efforts, persistent through different administrations to fund rural electrification. However, in the case of off-grid photovoltaic solutions, these efforts have consistently neglected allocating funds for operation and maintenance, which has seriously compromised the sustainability. Moreover, although Ecuadorian officials declared to favor stand-alone photovoltaic systems in the case of indigenous communities in the Amazon, we found that environmental or socio-cultural aspects have a minor role in the selection of these systems. Progress regarding environmental awareness, social acceptance, and cultural justice, is still needed for ensuring the sustainability of rural electrification efforts in the Ecuadorian Amazon.

Peru has historically been among the Latin-American countries with a low rural electrification rate. Aiming to improve this situation, the country conducted several electrification efforts in the last few decades that included off-grid photovoltaic (PV) solutions for remote areas (where the grid expansion was unviable). More recently, the government has also sponsored a ‘massive program’ that aims to deploy a minimum of 150,000 off-grid PV solutions in the upcoming years. In this paper, we assess the sustainability of rural electrification programs in Peru, paying special attention to the ongoing “massive program”. Our assessment considers four dimensions of sustainability (institutional, economic, environmental, and socio-cultural) and is based on an exhaustive qualitative document analysis complemented by semi-structured expert interviews. We found that the lack of strong formal institutions with a flexible and decentralized structure seriously compromises the sustainability of rural electrification efforts in Peru. Staff rotation and overlapping competences have caused disturbing changes and inhibited following a strategic line, while widespread outsourcing combined with weak controls have often affected the reliability of the deployed systems. Although cross subsidies have made off-grid PV systems affordable for users, systems often fell short of energy demand. Notably, we found that Peruvian officials appear to be unaware of the importance of local participation, and there is a significant mistrust between the government and the rural population (especially in areas where mining is extensive). As a consequence, most of the projects are still designed without the participation and engagement of the communities, which has frequently led to project failures, payment defaults, and inhibited seizing opportunities regarding productive uses of off-grid PV systems. We expect that our findings may help Peruvian institutions to address the most severe drawbacks affecting their rural electrification efforts based on off-grid PV systems.