People
Ing. arch. Lenka Maierová, Ph.D.

2024, Conference Booklet, University of Groningen), p. 44-44)

Historical monuments are often illuminated to prolong their attractiveness even after sunset. Using modern, powerful, energy-efficient electric light sources, light is directed onto their facades throughout the night. Environmental awareness draws attention to the light pollution caused. To limit the increase of light in the night environment, the Czech technical standard ČSN 36 0459 Limiting the adverse effects of outdoor lighting was introduced in 2023. It classifies the area into 5 zones of light environment according to their urban/natural character. Our study focuses on monitoring the current quantity and quality of light across these 5 zones and to verify the corresponding values set as the limits in the new technical standard. The measurements recorded lighting environment at selected 20 locations with historical monuments located in the different light zones. Values were measured from the perspective of a pedestrian and from a long-distance view. Both the baseline site brightness without added architectural lighting and while illuminating the historical monument with existing architectural lighting were reported. Based on these data, visual comfort was evaluated using luminance contrasts. The risk of glare caused by the installed architectural lighting was assessed. The results suggest that brightness control on the façade is useful for preventing over-illumination. When applied according to environmental zones, it allows to improve historic buildings without disturbing the harmony with nature and creating excessive light pollution.

2024, 9th European Medical and Biological Engineering Conference. Proceedings of EMBEC 2024, Wien, Springer), p. 248-255), ISBN 978-3-031-61624-2, ISSN 1680-0737

Bright-light therapy is one of the current techniques for preventing or supporting the treatment of several psychological disorders, such as seasonal affective disorder, bipolar disorder, postnatal depression etc. The paper deals with the design and realization of a control unit for phototherapy sources. General requirements on the control unit are specified and the principal approach to implement these requirements is described. Three different control unit designs are prepared for three specific devices - a light therapy chamber, a portable phototherapy device and a biodynamic lamp. The goal of the control unit is handling DALI LED controllers, wireless user communication and setting the therapy parameters up. The unit is realized as a simple embedded system equipped with the ESP-8266 or the WSP32-WROOM-32 microcontrollers. The system implements transmitting DALI commands and receiving the answers from the bus, user communication using the web based Graphical User Interface and therapy control. The specific implementation of the control unit for the phototherapeutic light chamber is described in more detail in the article. The design and implementation of the device were evaluated both in laboratory conditions and in real operation.

2024, 2024 International Conference on Applied Electronics, Plzeň, Západočeská univerzita v Plzni), p. 27-30), ISBN 979-8-3503-6229-9, ISSN 1803-7232

The article deals with the design and implementation of a control system suitable for controlling independent light sources using the Digital Addressable Lighting Interface (DALI). The system is based on using gateways between DALI bus and Wi-Fi, thus supporting most available DALI controlled devices. The devices are then controlled via the gateways from a central web application using a custom communication protocol built on Transfer Control Protocol (TCP). This allows for high flexibility of the system and remote control from different devices such as smartphones. The paper also describes one possible implementation of this control system. This implementation was successfully used for control of independent light sources in architectural lighting.

2024, Proceedings of the 2024 24th International Scientific Conference on Electric Power Engineering (EPE), VSB - Technical University of Ostrava (TUO)), ISBN 979-8-3503-4877-4, ISSN 2376-5631

This paper discusses the limits and benefits of satellite images used as a tool to identify sources of light pollution in the urban environments. It helps to detect the over illuminated or high-contrast zones that are often not obvious from human perspective, such as vertical landmarks illuminated by architectural lighting. Using the example of the historic centre of Karlovy Vary, a famous spa town in the Czech Republic, this study describes the process of data collection and evaluation, glare risk assessment and visual comfort of users. It identifies uncertainties and describes the benefits of the chosen approach.

2023, Conference Abstract Booklet, Calgary, University of Calgary), p. 119-120)

With the onset of modern technologies, electric light is becoming a more affordable commodity, contributing to the continuous growth of visible light pollution. Recent research studies point to the negative effects of light in the nighttime environment when excessive levels are used. Obtrusive light in public spaces is mainly caused by inadequate choice of the intensities of installed light sources, but also by incorrect set light flux direction and timing. This paper discusses the use of satellite imagery for identifying locations with obtrusive light in the structure of urban settlements.

2023, Sborník 1. ročníku mezinárodní konference Krajina Sídla Památky, Brno, Fakulta stavební), p. 46-55), ISBN 978-80-214-6158-1

Architekturní osvětlení plní estetickou funkci, zdůrazňuje význam historických objektů či významných veřejných prostranství. V době vzniku historických objektů nebylo umělé noční osvětlování fasád cenově ani technologicky možné. Architektura byla koncipována pro denní osvětlení, které je dynamické, má jiné směrování světla, a proto vytváří odlišné stíny a kontrasty. S příchodem nových výkonných světelných LED zdrojů se umělé osvětlení stále více zapojuje do atmosféry nočního prostředí, a to nejen při slavnostních příležitostech, ale i trvale. Intenzivní kužely světla tvoří nové, cizorodé prvky v noční krajině. Navyšování četnosti a intenzity elektrického osvětlení v nočním prostředí přispívá ke vzniku světelného znečištění, které zatěžuje přírodu a kulturní krajinu znehodnocuje. Studie analyzuje osvětlení historických objektů Národní kulturní památky Vyšehrad, hodnotí vliv osvětlení na památkovou hodnotu objektů a míru zásahu do přírodního prostředí parku. Pomocí jasové analýzy sleduje přiměřenost využití světla, identifikuje nadměrně osvětlené plochy a místa s rizikem vzniku oslnění od světelných zdrojů. Výsledky studie prokazují podíl architekturního osvětlení na vzniku světelného znečištění. Vysoká intenzita osvětlení a umístění světelných zdrojů, které nepodporuje plasticitu architektonického detailu, ovlivňuje historický kontext v prostředí. Vysoké kontrasty ovlivňující zrakovou pohodu a orientaci uživatele. Negativně působí světelné kužely zasahující do korun stromů. Nadměrná intenzita a nevhodné směrování světla se neblaze propisuje i do širšího kontextu města.

2022, PROCEEDINGS 14th European Lighting Conference LUX EUROPA 2022, Ostrava, Česká společnost pro osvětlování), p. 258-264), ISBN 978-80-11-02269-3

The paper is focused on the light produced by architectural lighting in urban environments, and its impacts on the aesthetic perception of both, the building and the whole urban composition of spaces, the effect on the visual comfort of users, and the environmental aspects. The case study is located in the Namesti Miru, Prague Czech Republic. It provides data on properties and the effects of public lighting and architectural lighting on the historical facades and their surroundings. It identifies the over-illuminated or high contrast zones, assess glare risk, visual comfort of the users. Further, based on the virtual model, scenarios for the lighting optimalisation are suggested.

2022, The IUPESM World Congress on Medical Physics and Biomedical Engineering 2022 Book of Abstracts, Singapore, MP Singapore Pte Ltd), p. 130-131)

One of the up-to-date techniques for preventing or supporting the treatment of mood disorders, such as seasonal affective disorder, bipolar disorder, postnatal depression etc., is full spectrum-light phototherapy. The paper deals with the design and realization of a control unit for a unique, balanced spectrum LED source. The light source is realized as a phototherapy chamber equipped with 54 LED panels, each panel with two LED channels with a different spectrum. Each channel is controlled by a separate DALI LED controller and dimmer. The goal of the project was to design and realize a control unit for handling DALI LED controllers, wireless user communication and setting the therapy parameters up. The control unit is designed as an independent device with an analogue part for handling DALI bus communication and a digital part, which implements transmitting and receiving DALI commands, user communication and therapy control. Both parts are isolated by optocouplers to prevent the interference of the control unit power supply and DALI line. The unit is realized as a simple embedded system with the ESP-8266 microcontroller; the device provides a wi-fi access point. The unit is mechanically realized as a DIN rail module. The firmware of the device is implemented in Processing language and consists of two parts, controller functions and an asynchronous web server. The controller part allows independent switching of the LED panels on and off, regulating brightness, timing the therapy etc. The web server part provides the user interface, such as buttons for starting therapy or civil light function and input boxes for setting parameters and values up. The presented research is a part of a large project concerning light therapy in psychiatric care. The realized device is implemented in a light therapy chamber currently used in the National Institute of Mental Health in Klecany near Prague.

2022, Conference Proceedings. YRSB22 – iiSBE Forum of Young Researchers in Sustainable Building 2022, 4th July 2022, Prague, Czech Republic, Praha, České vysoké učení technické v Praze), p. 39-46), ISBN 978-80-01-07107-6

Children aged 6 to 14 spend a large part of their time in school classrooms. The human eye in this age is evolving and is sensitive to the surrounding light conditions. For this reason, it is important to ensure that in the classrooms daylight quantity and quality requirements are fulfilled. The windows and the shading systems need to be designed to limit potential summer overheating and prevent users’ discomfort. Recently, a rapid increase in myopia progression in children has been reported. Possible causes are still unclear, but limited time spent outdoors, insufficient access to daylight and sunlight seem to be important triggers for myopia development. Moreover, data collected during pandemic Covid 19, when people were forced to stay at home, also suggest the irreplaceable role of a quality lighting environment on the healthy development of the eye. This study assesses the interaction of the classroom design, daylighting, and healthy eyesight.

2022, Scientific Reports, 2022 (12), ISSN 2045-2322

Improving indoor lighting conditions at the workplace has the potential to support proper circadian entrainment of hormonal rhythms, sleep, and well-being. We tested the effects of optimized dynamic daylight and electric lighting on circadian phase of melatonin, cortisol and skin temperatures in office workers. We equipped one office room with an automated controller for blinds and electric lighting, optimized for dynamic lighting (= Test room), and a second room without any automated control (= Reference room). Young healthy participants (n = 34) spent five consecutive workdays in each room, where individual light exposure data, skin temperatures and saliva samples for melatonin and cortisol assessments were collected. Vertical illuminance in the Test room was 1177 ± 562 photopic lux (mean ± SD) , which was 320 lux higher than in the Reference room (p < 0.01). Melanopic equivalent daylight (D65) illuminance was 931 ± 484 melanopic lux in the Test room and 730 ± 390 melanopic lux in the Reference room (p < 0.01). Individual light exposures resulted in a 50 min earlier time of half-maximum accumulated illuminance in the Test than the Reference room (p < 0.05). The melatonin secretion onset and peripheral heat loss in the evening occurred significantly earlier with respect to habitual sleeptime in the Test compared to the Reference room (p < 0.05). Our findings suggest that optimized dynamic workplace lighting has the potential to promote earlier melatonin onset and peripheral heat loss prior bedtime, which may be beneficial for persons with a delayed circadian timing system.

2022

2022

2022, Clocks & Sleep, Basel, MDPI AG), p. 438-439)

Abstract: Background: In today’s modern society, people spend most of their time in buildings where they are usually exposed to a mere fraction of daylight. This, combined with artificial lighting in the evening, leads to a decrease in the contrast of the photic signal between day and night, which is essential for proper circadian entrainment. Insufficient exposure to bright daylight has been associated with disrupted synchronization of circadian rhythms and related consequences for health, quality of sleep, mood and overall well-being. This study aimed to explore whether winter morning exposure to electric lighting with unique, daylight-mimicking qualities provided by an experimental phototherapy booth prototype called Sun spa would have a significant effect on mood, sleep quality and circadian rhythmicity of healthy volunteers. Methods: The ‘Sun spa’ is a cubic interior pavilion with a side of 2.5 m. The ceiling and half of one side wall serve as the source of the light. It provides a corneal illuminance above 8000 lx, which represents Equivalent Daylight Illuminance >7400 lx, with a CCT of 4500 K and a color-rendering index above 90. The light has a diffuse character and balanced spatial distribution with maximal luminance of 8000 cd/m2, which is similar to the natural sky. In this preliminary study, 18 participants were exposed to 30 min experimental lighting inside of the ‘Sun spa’ from 10:00 am to 10:30 am for two consecutive workweeks during the winter months. Participants were monitored by MotionWatch8 actigraphy devices starting 2 weeks prior to the experimental lighting exposure and ending 2 weeks post-exposure. Self-report questionnaires and scales on sleep quality and mood were administered 2 days before the experimental lighting exposure and one day after the experimental lighting exposure. Results: During the two-week experimental lighting exposure, the Interdaily Stability of the participants´ circadian rhythmicity was significantly increased compared to the two weeks prior and two weeks post-exposure. Self-report scales and questionnaires on anxiety (STAI), depressive symptoms (BDI) and positive and negative affect (PANAS) revealed no significant differences pre- and postexposure. Conclusions: While the experimental lighting exposure significantly increased the interdaily stability of the participants´ circadian rhythmicity during the two weeks of exposure, the intervention had no significant effect on self-report ‘mood’ correlates. However, part of the experiment, affecting a subset of participants, took place when the war had already started and participants reported it affected their sleep quality and emotions. Moreover, it remains to be determined to what extent the increased interdaily stability actually reflected the required commitment to attend the ‘Sun spa’ regularly

2021, Journal of Physics: Conference Series, Bristol, Journal of Physics: Conference Series (JPCS)), ISSN 1742-6596

Children between the ages of 6 and 14 spend much of their day in the school classrooms, where they are exposed to only a fraction of the daylight quantities typical for the natural outdoor conditions. This paper examines unilaterally and bilaterally illuminated classrooms in terms of quantitative and qualitative requirements for daylighting in classrooms in winter and summer. The results of measurements and simulations pointed to the advantages of bilaterally illuminated classrooms if compared to unilaterally illuminated ones. In winter, the windows placed on two opposite walls provide a significantly higher uniformity of daylight. In summer, in addition to the improved uniformity, these windows arrangement offers higher variability in shading strategies, resulting in the greater availability of daylight and better visual comfort. These factors can potentially prevent or limit the development of myopia.

2021, ERA 21 (122), p. 102-104), ISSN 1801-089X

Denní osvětlení v budovách není záležitostí pouze estetickou, dostupnost denního světla je zásadním kritériem kvality zdravého vnitřního prostředí. Volbou konkrétního typu okna, parametry jeho konstrukce a zasklení mohou architekti ovlivnit dostupnost denního světla a tím i kvalitu světelného prostředí.

2020, Biomedicines, 8 (12), p. 1-19), ISSN 2227-9059

The circadian clock regulates bodily rhythms by time cues that result from the integration of genetically encoded endogenous rhythms with external cycles, most potently with the light/dark cycle. Chronic exposure to constant light in adulthood disrupts circadian system function and can induce behavioral and physiological arrhythmicity with potential clinical consequences. Since the developing nervous system is particularly vulnerable to experiences during the critical period, we hypothesized that early-life circadian disruption would negatively impact the development of the circadian clock and its adult function. Newborn rats were subjected to a constant light of 16 lux from the day of birth through until postnatal day 20, and then they were housed in conditions of L12 h (16 lux): D12 h (darkness). The circadian period was measured by locomotor activity rhythm at postnatal day 60, and the rhythmic expressions of clock genes and tissue-specific genes were detected in the suprachiasmatic nuclei, retinas, and pineal glands at postnatal days 30 and 90. Our data show that early postnatal exposure to constant light leads to a prolonged endogenous period of locomotor activity rhythm and affects the rhythmic gene expression in all studied brain structures later in life.

2020, Časopis Stavebnictví, XIV (06-07/2020), p. 30-33), ISSN 1802-2030

V posledních měsících probíhá médii mnoho informací o tom, jak při pobytu venku dodržovat zvýšenou hygienu, jaké používat ochranné pomůcky, abychom se nenakazili koronavirem. Pro omezení negativních důsledků případné virové infekce je však neméně důležité starat se i o naši fyzickou a psychickou odolnost. Na lidský organismus má denní světlo významný vliv. Pravidelné střídání světla a tmy na Zemi odjakživa a velmi spolehlivě informovalo všechny živé organismy, zda je den, či noc, a zda tedy mají být připraveni na aktivitu, či odpočinek. A nejen to. Podle změny poměru dne a noci mohou také předvídat, zda se blíží teplé či studené roční období a na tuto změnu se nachystat. To, co prožíváme v době izolace, je jen zvýraznění stavu, který panuje již několik desetiletí. Lidé v moderní společnosti tráví více než 90 % času uvnitř budov a málo venku. Přitom v běžných domech jsou obvykle pouhé jednotky procent denního světla oproti venkovnímu prostředí. Většina umělých zdrojů světla navíc nemá takové spektrum, které by dokázalo přirozené denní světlo a sluneční svit zcela nahradit.

2019, SUSTAINABLE BUILT ENVIRONMENT D-A-CH CONFERENCE 2019 (SBE19 Graz), Graz, Graz University of Technology), ISSN 1755-1315

Knowledge and instruments of building physics (calculation methods and measuring procedures) can be used as key tools and perspectives to develop new components for building envelopes. This paper illustrates this fact by presenting the successful development of a roof window fulfilling higher requirements on reduction of overall heat losses and avoiding the risk of water vapor condensation on surfaces at very low external temperatures (thermal transmittance below 0.7 W/m2K in the first generation, close to 0.5 W/m2K in the second one) and better daylight distribution for the interior. This is the result of a publicly supported project with an industrial partner: from a general idea through detailed analysis of thermal performance in geometrical and material alternatives up to construction, prototyping, and verification by measurements and certification. Building physics tools applied in the project are discussed here together with lessons learned which are important for technical design. An effective shading system equipped with PV elements for energy smart harvesting is mentioned in the conclusion.

2019, CISBAT 2019 Proceedings, Bristol, Institute of Physics Publishing), ISSN 1742-6588

The lighting environment at indoor workplaces is important not only to provide vision and visual comfort, but also for light's direct influence on human physiology, cognitive performance and mood. The purpose of this ongoing study is to investigate the impact of a dynamic control of combined daylight and artificial lighting on office users' visual comfort as well as on alertness and cognitive performance. We are going to evaluate the impact of two different office lighting conditions in a quasi-real setting on subjective alertness ratings in healthy young participants over several days. We will compare an office with optimized daylighting and artificial lighting, operated by a new control system with a standard office room, where the lighting/shading can be changed manually. The aim of this balanced crossover within study design is to show that exposure to optimized dynamic lighting control over several days is superior on subjective alertness and glare indexes, when compared to a conventional lighting control. Here, we present some preliminary results from the first six participants on the comparison of subjective evaluations of alertness and the objective monitored (day-) light exposures and glare index Daylight Glare Probability (DGP) in the two different conditions over one week (five days) each.

2019, Energies, 12 (12), ISSN 1996-1073

This paper deals with a small but important component in a building envelope, namely roof windows in pitched roofs. Building physics methods were used to support the search for new solutions which correspond to the maximum extent for requirements for passive house level design. The first part of the paper summarizes the key phenomena of heat transfer, mainly based on a comparison of vertical windows in walls. The results of repeated two-dimensional heat transfer calculations in the form of parametric studies are presented in order to express the most important factors influencing thermal transmittance and minimum surface temperatures. Several configuration variants suitable for technical design are discussed. It was found that a combination of wood and hardened plastics in the window frame and sash is the preferred solution. The resulting thermal transmittance can be up to twice as low as usual (from 0.7 down to 0.5 W/(m(2)K), with further development ongoing. Surface temperature requirements to avoid the risk of condensation can be safely fulfilled. Concurrently, it is shown that the relative influence of thermal coupling between the window and roof construction increases with the improvement of window quality. Specific attention was given to the effect of the slanting of the side lining, which was analyzed by simulation and measurement in a daylight laboratory. The increase in thermal coupling due to slanting was found to be negligible. Motivations for specific building physics research are mentioned, such as the need to study the surface heat transfer in the case of inclined windows placed in a deep lining.

2018, 7th International Building Physics Conference IBPC2018 Proceedings, Syracuse, Syracuse University), p. 1331-1336)

This work highlights the BIPV potential in two urban areas with different characteristics at the city of Prague. Representative building blocks were selected and CitySim software tool was used for the assessment of the hourly irradiation profiles on each surface over one year period. Considering appropriate irradiation thresholds, suitable surfaces were then quantified. Integration criteria are discussed and suitable BIPV applications are proposed considering not only energy performance but also their impact on the quality of built environment. Results indicated that only 5.5% of the total area can be used in Vinohrady and 13.7% in Jizni Mesto contributing on average by 32% and 31% on the hourly electricity demand respectively.

2018

Plynulost provozu je primárním požadavkem na provoz v tunelech. Světelná informace, zobrazovaná na plochu bezpečnostní uzávěry SoftStop, může okamžitě informovat řidiče o přikázaném či doporučeném směru jízdy a tím během nestandardní situace snížit nebezpečí nepředvídatelných instinktivních reakcí řidičů uvnitř tunelu. Znamenalo by znamenalo snížení rizika vzniku dopravní nehody v okamžiku akutního uzavření jízdního pruhu či celého tunelu. Pro dobrou informační funkci světelné signalizace je třeba posoudit zřetelnost a čitelnost informace, a vhodnost jejího umístění v zorném poli. Současně je třeba zabránit případným negativním jevům, zejména oslnění. Měření provedené UCEEB ČVUT posuzuje, do jaké míry splňuje požadavky na zřetelnost informace. Měření světelné projekce bylo provedeno na prototypu uzávěry SoftStop instalované v laboratoři Západočeské university v Plzni.

2018

Podkladová studie o vztahu atraktivity prostoru a kvality života v kontextu nových technologií. Podkladová studie vymezuje a konceptualizuje základní oblasti a pojmy jako veřejná prostranství, vztah kvality života a veřejného prostranství, atraktivita prostoru, shrnuje současné technologické možnosti jakožto řešení specifických problémů obcí do 20 tisíc obyvatel, včetně definování vztahu a vlivu technologií na veřejné prostranství, shrnuje poznatky z terénního a online výzkumu ve 3 obcích Středočeského kraje (Buštěhrad, Mnichovice, Drahelčice), který se zaměřoval na vztah mezi atraktivitou veřejných prostranství a naplňováním potřeb obyvatel.

2018, Neuropsychobiology, 76 (1), p. 23-23), ISSN 0302-282X

Objectives: Diurnal changes in physiology and behavior are modulated by external factors such as light or temperature. Our objective was to test whether self-selected office lighting during a habitual waking period (16 hrs) would have an impact on subjective thermal comfort and objective measures of skin temperature in young morning and evening types (16/16), where preferred bed and wake times usually differ by several hours. Methods: The results obtained under a self-selected lighting condition (SSL; daylight and electrical lighting) were compared with a constant bright light (BL; 1000 lx) and a control condition (DIM, dim light). All participants came three times to the laboratory and remained under controlled constant posture conditions for 16 hrs, where room temperature was kept constant. Subjective thermal comfort was assessed hourly by visual analogue scales and proximal and distal skin temperatures were continuously recorded and expressed relative to midsleep. Results: Participants felt significantly colder in DIM than in BL or in SSL conditions (p<0.05), and subjective thermal comfort remained stable in BL and SSL conditions. Proximal (clavicula) and distal skin temperatures (hands) were significantly higher for SSL than for DIM or BL conditions. The time course for distal skin temperatures revealed for evening types significantly higher temperatures 5-6.5 hrs and 9-9.5 hours after habitual waketime, but only in BL, and not the other two conditions (p<0.05). The distal-proximal temperature gradient (DPG) was significantly correlated with subjective thermal comfort (Spearman Rho: 0.48, p<0.05). Conclusion: To conclude, self-selection of lighting at work might positively influence thermoregulatory functions regarding inter-individual differences, similar to what we have previously shown for subjective alertness, mood, wellbeing and melatonin secretion (Maierova et al. 2016). Acknowledgements: Velux Foundation Switzerland

2018, Světlo, 21 (1), p. 30-33), ISSN 1212-0812

V posledních několika stoletích nastaly zásadní změny v našem životním stylu. Rychlý rozvoj techniky a technologií ovlivnil i světelné prostředí, ve kterém žijeme. Má tato proměna vliv na naši společnost? Pro možnost komplexně posoudit rozsah a dosah změn, které v našem světelném prostředí proběhly, mapuje tento příspěvek vztah člověka ke světlu v různých historických etapách. Sleduje dopady na životní styl a kvalitu života člověka.

2018, 2018 VII. Lighting Conference of the Visegrad Countries (Lumen V4), Brno, Česká společnost pro osvětlování), ISBN 978-1-5386-7923-4

Impact of artificial light at night on sleep and health of humans and other living species is discussed among scientists. This paper analyses the properties of several commercially available light sources with regards to their effects on wildlife, human sleep, and health. A novel, environmentally considerate LED light source is introduced. Further, integration of this light source into the pilot biodynamic street lighting system is described. Based on the season and time of day, a control system changes the spectral composition of the light in order to provide healthy, sustainable lighting without compromising on safety, psychological needs or energy savings.

2018, Vytápění, větrání, instalace, 27 (6), p. 382-389), ISSN 1210-1389

This work highlights the Building-Integrated Photovoltaics (BIPV) potential in two urban areas with different characteristics in the city of Prague. The representative building blocks were selected and the CitySim software tool was used for the assessment of the hourly irradiation profiles in each surface over a one-year period. Considering appropriate irradiation thresholds, suitable surfaces were then quantified. Integration criteria are discussed and suitable BIPV applications are proposed considering, not only energy performance , but also their impact on the quality of the built environment. The Photovoltaic (PV) potential is compared with the estimated local electricity demand derived from the population distribution within the building block. Analysis indicated that only 5,5 % of the total area can be used in Vinohrady and 13,7 % in Jizni Mesto contributing by 32 % and 31 % on average on the hourly electricity demand, respectively. The PV generation exceeds the local non-baseload demand during the summer period, but is less significant during winter. A preliminary financial analysis reveals a payback time of 17,5 and 20 years for Vinohrady and Jizni Mesto areas, respectively. It is evident that, even in the areas with a sensitive built environment, adoption of solar energy is still possible for balancing local electricity needs.

2017, TZB HAUSTECHNIK SK, XXV. (05/2017), p. 22-24), ISSN 1210-356X

Dostatočné osvetlenie umožňuje dobrú orientáciu v priestore a vizuálnu komunikáciu s okolím. Svetelné prostredie ovplyvňuje súčasne celý rad biologických funkcií v organizme, preto treba zabezpečiť potrebnú dynamiku svetla.