• Energy Research

Effective design of solar photovoltaic (PV) systems requires accurate meteorological data for solar irradiance, ambient temperature, and wind speed. In this study, we aim to assess the reliability of satellite-based solar resource databases such as NASA, Solcast, and PVGIS by comparing them with ground-based measurements of global horizontal irradiance (GHI) from six locations in the Republic of Ireland. We compared satellite- and ground-based GHI data recorded between 2011 and 2012 and used Python-based packages to simulate solar power output for the six locations using both data types. The simulated outputs were then compared against metered power output from PV arrays at the sites. Ground-based GHI measurements demonstrate superior accuracy due to their acquisition at specific locations, offering increased spatial representativity. On the other hand, satellite GHI measurements, although reasonably accurate for many applications, cover broader regions with lower spatial resolution, leading to averaging effects that may not fully capture localized variations. This difference is reflected in the mean absolute percentage error (MAPE) values, with ground-simulated data showing low MAPE values, indicating strong alignment with reference observations, while satellite-simulated data exhibit a slightly higher MAPE, suggesting less precise estimates despite a strong correlation with ground-based measurements. This study demonstrates the relative reliability of satellite- and ground-based GHI data for accurate solar PV system design, emphasizing the practical implications for energy planners and engineers, and providing a strong enhancement for researchers working on forecasting solar energy yields using satellite databases. The Python-based PVLib package was utilized for the simulation, offering a robust framework for modeling and analyzing solar power systems, and its effectiveness in this context is discussed in detail.

Infrastructure Access Report Infrastructure: NTNU Full-Scale Wind Measurement Station User-Project: AWRA-ONCE. Advanced wind resource assessments in offshore, nearshore and coastal environments. This report describes improvements in coastal and offshore wind resource assessment methods. A model of the vertical profile of horizontal wind speeds is required in order to estimate wind resources at the rotor heights of proposed turbines. The specific goals were to (i) identify the best existing data sources and methods to incorporate atmospheric stability into vertical wind profile models and (ii) make recommendations for future offshore wind prospecting campaigns in order to adequately represent the effects of atmospheric stability. The coastal wind speed data and related support obtained from NTNU allowed us to validate atmospheric stability corrections at a coastal site with a long marine fetch in several wind sectors. This allowed us to test the applicability of methodologies developed at offshore sites. The bulk correction method using sea surface roughness and temperatures performed well for the overseas fetch sector. The diabatic profile improved the vertical wind profile prediction in comparison to the neutral profile suggesting that the wind flow regime is predominantly influenced by the marine boundary layer. The air methods also showed potential to calculate the stability, although a difficulty arose from the use of the 25m temperature readings which appeared to cause errors. Possible impacts include improved wind resource and energy yield estimates for offshore wind farm sites Infrastructure Accessed: NTNU Full-Scale Wind Measurement Station Infrastructure Manager: Dr. Lars Saetran

The ever-increasing demand for electrical power in Nigeria, coupled with a limited supply, have restricted the nation's socioeconomic development. The country’s policymakers, aware of this, have formulated and enacted energy development policies in recent years targeted at diversifying the current electricity mix and increasing electrification to rural settlements.Despite these efforts, electricity infrastructure projects have been sidelined, power outages are common and grid unreliability is costing industry significant amounts to secure the electricity supply necessary for business sustainability and profitability.This paper presents the current state of the electricity industry in Nigeria and argues the case for integration of renewable energy technologies. A case study is presented based on electricity cost information collected from a survey of Nigerian industry. Three future electricity supply scenarios are presented: a do-nothing or business-as-usual scenario; a scenario of increased reliance on gr...

In recent years, the sustainability of wind power has been called into question because there are currently no truly sustainable solutions to the problem of how to deal with the non-biodegradable fibre-reinforced polymer (FRP) composite wind blades (sometimes referred to as “wings”) that capture the wind energy. The vast majority of wind blades that have reached their end-of-life (EOL) currently end up in landfills (either in full-sized pieces or pulverized into smaller pieces) or are incinerated. The problem has come to a head in recent years since many countries (especially in the EU) have outlawed, or expect to outlaw in the near future, one or both of these unsustainable and polluting disposal methods. An increasing number of studies have addressed the issue of EOL blade “waste”; however, these studies are generally of little use since they make predictions that do not account for the manner in which wind blades are decommissioned (from the time the decision is made to retire a turbine (or a wind farm) to the eventual disposal or recycling of all of its components). This review attempts to lay the groundwork for a better understanding of the decommissioning process by defining how the different EOL solutions to the problem of the blade “waste” do or do not lead to “sustainable decommissioning”. The hope is that by better defining the different EOL solutions and their decommissioning pathways, a more rigorous research base for future studies of the wind blade EOL problem will be possible. This paper reviews the prior studies on wind blade EOL and divides them into a number of categories depending on the focus that the original authors chose for their EOL assessment. This paper also reviews the different methods chosen by researchers to predict the quantities of future blade waste and shows that depending on the choice of method, predictions can be different by orders of magnitude, which is not good as this can be exploited by unscrupulous parties. The paper then reviews what different researchers define as the “recycling” of wind blades and shows that depending on the definition, the percentage of how much material is actually recycled is vastly different, which is also not good and can be exploited by unscrupulous parties. Finally, using very recent proprietary data (December 2022), the paper illustrates how the different definitions and methods affect predictions on global EOL quantities and recycling rates.

Fiber reinforced polymer (FRP) composite materials have been used in a variety of civil and infrastructure applications since the early1980s, including in wind turbine blades. The world is now confronting the problem of how to dispose of decommissioned blades in an environmentally sustainable manner. One proposed solution is to repurpose the blades for use in new structures. One promising repurposing application is in pedestrian and cycle bridges. This paper reports on the characterization of a 13.4-m long FRP wind blade manufactured by LM Windpower (Kolding, Demark) in 1994. Two blades of this type were used as girders for a pedestrian bridge on a greenway (walking and biking trail) in Cork, Ireland. The as-received geometric, material, and structural properties of the 27 year-old blade were obtained for use in the structural design of the bridge. The material tests included physical (volume fraction and laminate architecture) and mechanical (tension and compression) tests at multiple locations. Full-scale flexural testing of a 4-m long section of the blade between 7 and 11 m from the root of the blade was performed to determine the load-deflection behavior, ultimate capacity, strain history, and failure modes when loaded to failure. Key details of the testing and the results are provided. The results of the testing revealed that the FRP material is still in excellent condition and that the blade has the strength and stiffness in flexure to serve as a girder for the bridge constructed.

With the global increase in the deployment of photovoltaic (PV) modules in recent years, the need to explore and understand their reported failure mechanisms has become crucial. Despite PV modules being considered reliable devices, failures and extreme degradations often occur. Some degradations and failures within the normal range may be minor and not cause significant harm. Others may initially be mild but can rapidly deteriorate, leading to catastrophic accidents, particularly in harsh environments. This paper conducts a state-of-the-art literature review to examine PV failures, their types, and their root causes based on the components of PV modules (from protective glass to junction box). It outlines the hazardous consequences arising from PV module failures and describes the potential damage they can bring to the PV system. The literature reveals that each component is susceptible to specific types of failure, with some components deteriorating on their own and others impacting additional PV components, leading to more severe failures. Finally, this review briefly summarises PV failure detection techniques, emphasising the significance of electrical characterisation techniques and underlining the importance of considering more electrical parameters. Most importantly, this review identifies the most prevalent degradation processes, laying the foundation for further investigation by the PV research community through modelling and experimental studies. This allows for early detection by comparing PV performance when failures or degradation occur to prevent serious progression. It is worth noting that most of the studies included in this review primarily focus on detailing failures and degradation observed in PV operations, which can be attributed to various factors, including the manufacturing process and other external influences. Hence, they provide explanations of these failure mechanisms and causes but do not extensively explore corrective actions or propose solutions based on either laboratory experiments or real-world experience. Although, within this field of study, there are corresponding studies that have designed experiments to suggest preventive measures and potential solutions, an in-depth review of those studies is beyond the scope of this paper. However, this paper, in turn, serves as a valuable resource for scholars by confining PV failures to critically evaluate available studies for preventative measures and corrective actions.

53,000 tonnes of blade waste from on-shore wind farms will potentially be generated in Ireland by 2040. The recycling of blades, which are made from composite material, is costly and thus far no high volume recycling solution exists. Repurposing blades into second life structures is an alternative which is gaining in popularity, but has many challenges. Green Public Procurement has the potential to help drive demand for blade products in Irish public works. The Re-Wind project has generated a Design Atlas with 47 blade product concepts and these are screened for their ability to overcome repurposing challenges. Three Irish scenarios are developed based on this ranking, maximal utilization of the blade, and on the end customer. Life Cycle Assessment is used to determine the marginal environmental impacts of the raw material substitution provided by the use of blade material. Focusing on greenhouse gas emissions, an estimated 342 kg CO2 e can be saved for every tonne of blade waste used in these scenarios. Blade substitution of steel products was found to provide the most impact, followed by substitution of concrete products. Although repurposing is unlikely to offer an end-of-life solution for all Irish blade waste, the use of 20% of this material annually would divert 315 tonnes of blade waste from landfill, as well as avoiding emissions of 71,820 kg CO2 e. Green procurement has the potential to create a demand for repurposed blade products, which in turn could create jobs in high unemployment areas. Utilization of repurposed, local material could contribute to creating resiliency in supply chains. Both job creation and supply chain resiliency are essential for a post-Covid recovery in Ireland.