Manuel Jesus Blanco

• Doctor of Philosophy (Ph.D.) Applied Physics, University of Massachusetts Lowell (USA); Doctor of Engineering Industrial Engineering, University of Seville (Spain); Master of Science Energy Engineering University of Massachusetts Lowell (USA)
• Senior Scientist at German Aerospace Center (DLR)

An innovative approach for the characterization of the mirror geometry of Concentrating Solar Thermal (CST) plants is presented in this article. The approach takes advantage of the current advances in the commercial unmanned aerial vehicle (UAV) technology to perform airborne, close-range photogrammetry for accurate characterization of the mirror’s...

After many years of fruitful collaboration in the field of research infrastructures (RIs) for concentrated solar power/solar thermal energy applications, several European countries decided to apply to the European Commission to go a step forward and create a European Research Infrastructure Consortium (ERIC), a new legal form of association which p...

The efficiency of heliostat fields is analyzed in terms of mirror density. It is shown that it is possible to estimate the blocking and shadowing losses without ray tracing or polygon clipping. The calculations are based on general geometric properties and provide a kind of upper limit for heliostats with various mirror shapes and tracking systems....

Countries of the Eastern Mediterranean and Middle East region are far off the trajectory required to stabilise the global climate. Being responsible for about threequarters of greenhouse gas emissions, the energy system has to bear most of the burden of the decarbonisation effort. In such a context, this report identifies three pillars that need im...

The standard Concentrating Solar Thermal (CST) mono-tower technology, which uses one receiver placed on top of a tower to which all heliostats in the heliostat field aim to, is regarded as one of the best and most promising technologies for various CST-driven applications, namely CST power plants, solar metallurgical processes, thermochemical produ...

This study presents an analysis of the theoretical upper limits to the mean annual optical efficiency of the Light Collection and Concentration (LCC) subsystem of a solar tower system, which is the subsystem composed of the heliostat field and the active surfaces of the receiver that capture the concentrated solar radiation sent by the heliostat fi...

The optimization of solar tower power plants and other concentrating solar power (CSP) systems requires a customized approach for interpolation over the annual sun path. A good interpolation should predict accurately the efficiency of the system for different positions of the sun by using a small number of sampling points. This is very important to...

Artificial Intelligence (AI) is increasingly playing a significant role in the design and optimization of renewable energy systems. Many AI approaches and technologies are already widely deployed in the energy sector in applications such as generation forecasting, energy efficiency monitoring, energy storage, and overall design of energy systems. T...

Integrals that are of interest in the analysis, design, and optimization of concentrating solar thermal systems (CST), such as the annual optical efficiency of the light collection and concentration (LCC) subsystem, can be accurately computed or estimated in two distinct ways: on the time domain and on the spatial domain. This article explores thes...

This article presents an innovative approach for optimizing the dimensions of cylindrical receivers for solar tower systems. In this approach, a single set of rays, representative of a complete annual ray-tracing simulation of the solar tower system, is used and processed to evaluate numerous receiver designs simultaneously and to select the optimu...

The heliostats with two tracking axes are considered, and the method is presented to find the tracking angles for reflection of sun light to a given target. An important advantage of the method is that the tracking axes are not required to be orthogonal like in azimuth-elevation, tilt-roll or target-aligned heliostats. All of these configurations a...

Daily reflectance measurements on mirrors used in CSP applications were obtained over a period of 4 months to monitor soiling as a function of meteorological and environmental parameters. The mirrors were placed at 45° increments from face down to face up, and the parameters monitored included temperature, relative humidity, wind speed, rainfall an...

The algorithm for computing the solar vector of (Blanco et al., 2001) is revisited to improve its accuracy in the period 2020–2050, a period for which the algorithm was not initially designed. The resulting improved algorithm achieves a 25% decrease in the average error of the angular deviation with respect to the true solar vector (from a mean err...

The efficient and productive operation of a Concentrating Solar Thermal (CST) plant depends upon knowledge of the mean reflectance of the solar collector field, as the levelized cost of electricity has a one-to-one ratio with reflector optical performance. Considering the size of such collector fields, a continuous detailed survey of the whole fiel...

The tracking of heliostats with arbitrary orientation of the primary and secondary axes is considered, and the explicit formulas are derived to find the tracking angles for a given position of the sun. It is shown that the inverse kinematics problem leads to a quadratic equation and has two solutions in general case. The solutions can be obtained i...

Sunshape and reflector surface slope error distributions are significant elements in modelling the optical behaviour of a concentrating solar power system. Different optical modelling tools implement these elements with various approaches. Discrepancies can easily accumulate in simulations of a large optical system as a result of incorrect implemen...

This article presents an overview of the status of CST technologies, their cost, and their future trends. The information regarding the trends in CST technologies is based on the informed opinion of the authors, many of which have decades of experience in the CST field in academia and industry. Thus, it does not pretend to be an exhaustive list of...

The acausal and object-oriented language Modelica was chosen to develop the overall system-level model of the Cyprus Institute’s Concentrating Solar Power (CSP) and Desalination of Sea Water (DSW) proof-of-concept at the Platform for Research, Observation, and Technological Applications in Solar Energy (PROTEAS) facility in Cyprus. This model build...

Critical factors in modelling the optical behaviour of solar concentrators are firstly, sunshape, which is the angular distribution of the incident solar irradiance, and secondly, the slope error distribution of the reflecting surfaces. Different optical modelling tools address the implementation of these factors differently, and discrepancies can...

This paper presents the results from the workshop organized by the NEXTOWER project aimed at creating a cluster and exchange forum for projects and research activities in the area of Concentrated Solar Power. Synergies and experiences were shared, common difficulties, specially when dealing with innovative materials were found and discussed and new...

The performance of a heliostat field is directly related to the optical quality of the mirror surfaces used to reflect solar radiation onto the receiver. In this paper, two methods are used to characterize the actual shape of the surface of a heliostat, using laser scanning and photogrammetry. The accuracy of each technique for the intended purpose...

This paper presents FluxTracer, an advanced open source computer tool to assist in the analysis, design, and optimization of solar concentrators and receivers. FluxTracer is a postprocessor for Monte Carlo ray tracers used to simulate the optical behavior of solar concentrating systems. By postprocessing the rays generated by the ray tracer, FluxTr...

A collaboration between the Energy Environment and Water (EEWRC) and Science and Technology in Archaeology (STARC) Research Centers of The Cyprus Institute has been established with the aim of combining techniques, methodologies, and software analysis from the respective fields to characterize the optical surface of a heliostat. Both imaging and ra...

For commercial solar tower systems of relevant size, state of the art of light collection and concentration (LCC) subsystems (heliostat field plus receiver envelope) do not achieve annual optical efficiencies larger than 65%. Achieving optical efficiencies substantially higher than that requires departing from the traditional mono-tower design. Alt...

FluxTracer is a new open source computer program being developed by the Cyprus Institute in close collaboration with the Australian National University. It is an experimental post-processor for Monte Carlo Ray Tracer (MCRT) simulations. By post-processing the rays generated by a MCRT, FluxTracer can provide information useful to analyze the distrib...

This study presents an analysis of the theoretical limits to the annual optical efficiency of the Light Collection and Concentration (LCC) subsystem of a solar tower system. The upper limits examined range from highly theoretical to relatively realistic. The concept of an “ideal” LCC subsystem is introduced as a vehicle to consider incrementally th...

The light collection and concentration subsystem (LCCS) of any concentrating solar thermal (CST) system is composed of the surfaces that collect and concentrate the sunlight and of the input surfaces of the receivers, or receivers’ envelopes, where the light is concentrated. For all commercial CST technologies the LCCS is, together with the power b...

This Brief Note presents a general and efficient clustered-based methodology for the generation of high-frequency coupled global horizontal irradiance (GHI) and direct normal irradiance (DNI) series, based on the envelope clear sky and Dynamic Paths concepts. The procedure for generating 1-min synthetic irradiance data assumes that the effect of pa...

The sunshape and mirror surface slope error are two main factors that influence the characteristics of incoming and reflected solar beams in a solar concentrator. Different optical modelling tools, however, address these two factors with different methods and simplifications. In this study, simulation methods are reviewed in five optical modelling...

In order to facilitate comprehensive economic modeling of CSP/STE power plants realistic long-term meteorological datasets with temporal resolution down to 1 minute is a main premise. Currently available standard datasets do not fulfil this premise. The datasets also need to combine the high quality of well-maintained ground-based irradiance measur...

The demands on the quality and contents of solar and meteorological data sets increase rapidly with the growth in Concentrating Solar Power (CSP) and other solar energy systems. This document is a delivera-ble of the SolarPACES Project: “Beyond TMY,” and it is produced as Recommendations for what to do next and a road map of future improvements in...

The Heliostat Cost Down Scoping Study is a preliminary activity led by the ANU, part of the ASTRI Node 1 program to reduce capital expenditure across an entire CSP solar field, and is the first step in a heliostat cost-reduction project to be carried out over the 8 year ASTRI program. The context for this report is the annual growth of the global C...

After decades of research and development, concentrating solar thermal (CST) power plants (also known as concentrating solar power (CSP) and as Solar Thermal Electricity or STE systems) are now starting to be widely commercialized. Indeed, the IEA predicts that by 2050, with sufficient support over ten percent of global electricity could be produce...

With the strong dependence of national economies on energy, interest in solar energy potential assessments is increasing in countries with high solar radiation levels. This article reviews four methodologies proposed in the literature by four different organizations (IDAE, Greenpeace, NREL, and DLR) and proposes a new one (LRS) for assessing the po...

A systematic approach is presented for the sampling and interpolation over sun path. The annual sun path is described in terms of the ecliptic longitude and hour angle so that all possible positions of the sun are mapped on a rectangular domain. This enables the use of many efficient algorithms, and the bicubic interpolation with Catmull–Rom spline...

A better efficiency of heliostat field implies a denser layout, but shading and blocking losses impose limits on how close heliostats can be deployed. These limits can be analysed by modelling and simulating the optical behaviour of a small group of heliostats arranged on a lattice with adjustable azimuthal and radial spacings. The optimal spacings...

This paper examines the potential of sodium receivers to increase the overall solar-to-electricity efficiency of central receiver solar power plants, also known as solar tower systems. It re-visits some of the key outcomes and conclusions from past sodium receiver experiments, in particular those at Sandia National Laboratories and Plataforma Solar...

The Australian Solar Thermal Research Initiative (ASTRI) aims to develop a high optical quality heliostat with target cost – manufactured, installed and operational – of 90 AUD/m2. Three different heliostat design concepts are described, each with features identified during a prior scoping study as having the potential to contribute to cost reducti...

The inherent variability of the solar resource presents a unique challenge for Concentrating Solar Power (CSP) systems. Incident solar irradiance can fluctuate widely over a short time scale, but plant performance must be assessed for long time periods. In this paper, the concept of Plausible Meteorological Year (PMY) along with the Multiscale Stoc...

A precise knowledge of the high-frequency variation of the incoming Direct Normal solar Irradiance (DNI) is required for an accurate design and operation of Concentrating Solar Thermal Power (CSTP) plants. The time resolution of the numerical weather prediction models or satellite derived solar irradiance data are typically limited to 1-h (at best...

The knowledge of the high-frequency temporal evolution of Direct Normal solar Irradiance (DNI) reaching the ground is a key parameter in the design and operation of Concentrating Solar Thermal Power (CSTP) plants, as instantaneous flickering nature of DNI can affect power system operations in several ways. In this study, a methodology to increase t...

In recent years, many researchers are suggesting that statistical approaches are needed to achieve sound estimates of the economic feasibility of commercial Concentrating Solar Thermal Power (CSTP) plants. A key element of such statistical approaches is the capacity of generating large series of high-frequency years which are consistent with the es...

This paper describes the first steps given in order to develop a methodology to generate solar radiation maps using information from different sources. First, it is based on a meteorological simulation over the area of interest by means of a Numerical Weather Prediction Model. After that, a cluster method is applied to identify zones with similar f...

This paper analyses the potential for cost reduction that can be achieved by Solar Tower systems concepts that use a combined Brayton – Rankine cycle, in which the Brayton cycle is decoupled from the Rankine cycle by means of the thermal storage system. In such decoupled cycles, the heat rejected by the Brayton cycle, instead of being directly used...

Yield analysis is a crucial task during project development of solar thermal power plants. At the moment, numerous system models and assessment methodology are used by the different stake holders. These models often lack validation, and no standard or benchmark for comparison yet exists for electricity yield analysis of CSP plants. This situation h...

This paper analyzes the influence of operational strategies on the performance of parabolic trough (PT) solar power plants with the aid of SimulCET a computer program for the simulation of the energy behavior of PT plants developed by the National Renewable Energy Centre of Spain (CENER). SimulCET uses state of the art techniques to simulate solar...

Due to the high capacity of solar thermal power plants (50 MWel and more) and large required investment, concentrating solar power (CSP) projects are subject to an extensive project development process. Predicting the energy yield of a CSP plant is a crucial task in this process. Mathematical models predicting the system’s energy yield are required...

Electricity yield projection is one of the essential tasks related to concentrating solar thermal power plants. Currently, the project engineers and other stakeholders cannot refer to standardized methods for calculation of the annual electricity outcome of such plants. In autumn 2010, the first steps were taken to initiate an international project...

Present needs in concentrating solar power systems require knowledge of the solar irradiation temporal evolution. Daily or hourly generation of irradiation synthetic series is normally used in the estimation of solar resource, as measured series of radiation are only available for a reduced number of locations. Notwithstanding, the flickering natur...

Variability in global and direct irradiation series generation: scope and limitations. Abstract The synthetic generation of hourly global horizontal irradiation (GHI) series allows the estimation of solar radiation potential by allowing the filling of gaps in records of daily or hourly values. In addition, synthetic generation of GHI can provide an...

Tonatiuh is an Open Source, Monte-Carlo ray tracer, object-oriented computer program for the design, simulation, and analysis of the optical and energy behavior of solar concentrating systems, which is being developed by the National Renewable Energy Centre of Spain (CENER) in collaboration with the University of Texas at Brownsville (UTB), with th...

Current status of concentrating solar power technology with thousands of solar collectors under installation worldwide, demand a better quality control not only during erection and assembly but also while operating and after several years of operation. The final optical quality of the solar collectors on field has a strong influence in the final pe...

This paper presents a validation of DinaCET using experimental data from more than one year operation of the Nevada Solar One power plant. DinaCET is a computational scheme for the generation of stand-alone dynamic computer programs that simulate the transient behavior of parabolic trough solar thermal power plants. The programs generated by DinaCE...

This paper presents the comparison of two prediction schemes for global solar irradiance forecast, developed by CENER and by the University of Oldenburg respectively. CENER’s scheme is based in applying a post processing treatment to the weather forecasts generated by the Numerical Weather Prediction (NWP) model Skiron, while the University of Olde...

ABSTRACT

The Tonatiuh project consists of the design, development, implementation, verification, and validation of Tonatiuh, an open-source advanced object-oriented program, that using distributed computing, Monte Carlo ray tracing, and the best 3D user interface technologies available today, aims to provide a sophisticated and efficient environment for the...

The Tonatiuh software development project consists in the design, development, implementation, verification and validation of Tonatiuh: an open-source advanced object-oriented program, that using distributed computing, Monte-Carlo Ray tracing, and the best 3-D user interface technologies available today, will provide a sophisticated and efficient s...

This paper explores the thermodynamic limits of solar thermal systems using absorber surfaces with high angular selectivity. It shows that theoretical considerations regarding the behavior of non-concentrating solar thermal systems are not enough in themselves to rule out their use in high-temperature applications. In fact, the paper demonstrates t...

Many people associate solar energy directly with photovoltaics and not with solar thermal power generation. Nevertheless, large commercial concentrating solar thermal power plants have been generating electricity at a reasonable cost for more than 15 years and some new solar thermal power plants are soon to be erected. This paper compares the two t...

High-concentration solar thermal systems require the Sun to be tracked with great accuracy. The higher the system concentration, the greater this accuracy must be. The current trend in solar concentrator tracking systems is to use open-loop controllers that compute the direction of the solar vector based on location and time. To keep down the price...

One of the short-term priorities for renewable energies in Europe is their integration into communities and energy islands for local power supply (blocks of buildings, new neighborhoods in residential areas, shopping centers, hospitals, recreational areas, eco-parks, small rural areas or isolated ones such as islands or mountain communities). Follo...

This paper reports on the first phase of the Colón Solar Project, originally conceived as the hybrid repowering of an existing thermal power plant, with the addition of a gas turbine in a topping configuration integrating thermal energy (steam) produced by a solar system. However, the project developed in a changing economic environment, in which a...

In future central receiver systems, secondary concentrators may make it possible to reach high temperature and to relax design requirements on heliostats. In the course of evaluating the high-flux receiver at the Almeria CRS plant, it was proposed that a terminal concentrator would allow the use of the plant for high flux experiments and at the sam...

The paper presents an overview of the plant history to date (August 31, 1984) and also ascertains some of the principal operating characteristics for the major components/systems, heliostats, receivers, steam generator, and electrical generator. Details are given of the days of operation, operating hours, and major outages that have occurred at the...

In this paper the interface between optics (incident flux distributions) and thermodynamics (temperature distributions) is analyzed and the ASR thermal performance is evaluated. The thermal analysis of the receiver has been performed with the thermodynamic model THERESA.

This paper describes a computer program which has been developed to control the power sent to a receiver. The program, ‘CONTROL’, takes heliostats in and out of track in ‘real time’ to achieve this goal.

The favorable heat transfer characteristics of sodium makesit possible to collect concentrated solar radiation at medium high temperatures in small active areas, and therefore, with relatively low losses. However, because of the intermittent nature of the solar source, the receiver and the sodium pump controls must be designed and operated so as to...

Includes bibliographical references. Thesis (M.S.)--University of Lowell, 1988. Vita. Microfiche. s

Vita. Typescript. Thesis (Ph. D.)--University of Massachusetts. Lowell, 1993. Includes bibliographical references.