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Ass. Prof. .Dr. Roy-Olive Adams †,  Dr. Arch. Ognyan Simov‡,  Prof. Dr.  Manfred Sohn†

The primary consideration in the design of a single-family residential building is the creation of a comfortable indoor living environment at minimum energy consumption. The design process consists of a series of functional, structural, aesthetic and economic problems to be addressed. The clear definition of these problems as well as the success of the final results depends on the information and careful analysis of the existing conditions. 

In the majority of the cases, the design process of a single-family house in Bulgaria takes into account only construction cost savings. This often leads to the complete disregard of the indoor thermal conditions and the energy efficiency of the building. Designers do not consider the occupancy type and duration, which can prove to be essential to optimizing the energy characteristics of the building. During the times of World Energy Crisis, the construction of energy efficient buildings is a must. These buildings still have to provide high quality living conditions without significant increase of construction costs.

There are four primary occupancy duration options in residential buildings:

• Regular/Permanent (a primary residence)
• Seasonal (winter or summer vacation homes)
• Episodic (during the entire year but only for short periods of time, primarily during the weekend)
• Combined (seasonal + episodic occupancy)

Each one of those occupancy options influences the selection of overall building massing, structure and building materials as well as the amount and specifics of all energy efficiency improvements that may be necessary. At the same time, the quality of the living conditions depends on functionality, favorable and relatively constant indoor temperature, controlled air flow, warm interior surfaces during the winter periods or cool during the summer, relative humidity in the spaces (without surface condensation), no microorganism growth (mold and mildew) within the building envelope.

At the “Permanent” occupancy mode, optimal energy efficiency during the cold winter periods could be achieved by maximum containing of the heat from heating devices as well as absorbing the natural solar radiation received by the building interior.

Satisfying both requirements, however, can be quite contradictory, unless addressed and balanced during the design process. Both winter and summer conditions require a compact building mass (maximum building area within minimum envelope surface) in order to achieve maximum building energy efficiency.  Maximizing the glazing surfaces on the south and east building facades are necessary for the maximum accumulation of solar radiation during the winter. Roof overhangs have to be appropriately sized in a way which does not prevent the solar radiation from entering the building interior through the glazing. All covered balconies have to be placed in such a manner as to minimally shade the interior spaces connected to them (living rooms, bedrooms, etc.). The glazing materials used are of great significance as well. Insulated glazing panels with low overall heat transfer coefficient values (U-value) and clear glass which allows a maximum amount of solar radiation to enter the space interior, are the most appropriate.

During the summer the most important building features for maximum energy efficiency include appropriate building insulation, high thermal resistance of the building materials, protection of exterior building surfaces and interior spaces against direct sun exposure and overheating. Retractable awnings and window louvers can be used to restrict the overheating of the building interior during the summer months.  

There is another set of requirements for the building materials, assemblies and elements in buildings which are primarily used with “Episodic” and “Combined” occupancy duration. “Episodic” occupancy mode in single-family residential buildings is typical for vacation residential areas (in radius of 60 to 100km from city center) around big European cities which are important commercial or industrial centers. A large number of the “upper middle class” households (families of lawyers, doctors, bankers, etc.) own a residence in proximity to the city center, used primarily during the week and a second (vacation) home in the suburban areas outside of the city boundaries, which is used during the weekends and holidays. The second residence use represents a typical example of episodic occupancy in single-family residential buildings. This social group is open to and considerate of innovative concepts and methods for energy efficiency and preservation of natural energy resources. This awareness and sensitivity is due to their higher education and forward environmental thinking. A lot of those people are also among the leaders in the domestic applications of energy efficient and environmentally friendly products. Their new or old but renovated residences often have systems for automated control of the microclimate, remote or internet control of the central HVAC systems.

Energy efficiency in episodic occupancy residential buildings is of great importance, especially during the winter months in Northern and Central Europe. The fact that the buildings are occupied primarily for just two days during the week requires that their initial design and material selection is such that they give the spaces the ability to warm up quickly and offer optimal indoor microclimate with minimum energy consumption.

Single-family residential buildings which are used as primary residences are typically build of solid materials such as reinforced concrete and ALC masonry unit walls with insulation placed on exterior surface of enclosing wall (Building 1 in Table 1). Such construction type is able to accumulate heat through its thermal mass and maintain relatively constant microclimate which is not easily affected by exterior temperature variations. It is not however very appropriate for episodic occupancy duration.

Testing proves that much more appropriate are lightweight construction types with high efficiency wall insulation (Building 2 in Table 1) which can provide rapid warming of spaces with 15% less energy consumption (refer to Table 1).

Table 1

Rates for achieving optimal indoor thermal conditions in buildings with “Episodic” occupancy duration
1	2	3	4	5
Construction Type   Controlled Variable	Building 1 Solid Construction 36.5cm ALC masonry wall + 5cm Styrofoam insulation U = 0.3 W/m2K (placed on exterior of wall)	Building 2 Light Wood Construction Plywood walls + 15 cm fiberglass insulation U = 0.3 W/m2K	Building 1 with thermal ceramic coating, applied at all wall and ceiling surfaces	Building 1 with thermal ceramic coating with Low-e component, applied at all wall and ceiling surfaces
Time to reach 20oC	7hours 23minutes	6hours 12minutes	7hours 6minutes	6hours 55minutes
Interior surface temperature of the enclosing wall	14.1 oC	16.8 oC	15.7 oC	15.3 oC
Temperature of test body placed inside the space	17.3 oC	17.8 oC	18.1 oC	18.7 oC
Total consumed energy	10.84 kWh	9.18 kWh	10.59 kWh	9.82 kWh

 

Table 1 represents results of testing on two types of buildings with the same floor plan and overall massing, one of which is of “solid” construction type and the second is of “lightweight” construction type. Measurements are taken in a spaces with total floor area of 12m² and 1.5kW heater which is turned on maximum and automatically shuts down when the room air temperature reaches 20 ^oC. Air temperature, interior surface temperature of enclosing walls (necessary for surface condensation risk assessment) as well as temperature of test body placed in the space is measured.  The results of the test body temperature measurement gives information about the amount of energy consumed by the enclosing assemblies and the portion that is received by the space occupants. In other words, a higher test body temperature attests to the greater indoor thermal comfort that occupants experience in the spaces.

Despite the construction type utilized, the overall heat transfer coefficient (U-value) for the enclosing assemblies is the same, which in a stationary heat transfer mode means equal value. U-values of the glazing are also the same – U=0.9W/m²K, such values can be achieved if insulated glazing panels with Low-e film are used for all exterior glazing.

Initial measurements presented in columns 2 and 3 of Table 1 are taken in 2008. Results recorded for Building 1 which was used in episodic occupancy duration mode prove to be insufficient. Therefore additional improvement work was conducted in 2010 and 2011, results of which are recorded in columns 4 and 5 of Table 1.

Summary of the space thermal characteristics of the building used with “episodic” occupancy duration include:

• Building of a “lightweight” construction type (Building 2) is fundamentally much more appropriate for such occupancy, than a “solid” construction type building (Building 1). During the winter period of 2009, Building 2 records 336kWh less energy consumption at equal occupancy duration rates compared to Building 1.
• Test body temperature remains 0.5 ^oC lower in Building 1, even when the air temperature has reached and has been maintained constant at 20 ^oC. These results explain the feeling of cooler indoor environment, a concern expressed by the space occupants. The test body temperature in both test buildings reaches equal values only when the air temperature in Building 1 is increased to 22 ^oC. This inevitably leads to higher energy consumption.
• Besides the higher energy consumption of Building 1 for reaching comfortable indoor environment, it also shows lower surface temperature of the interior surfaces of the enclosing walls. This resulted in surface condensation in some areas, which by the end of 2009 caused mold growth on the walls and ceiling. The condition required repainting of the space walls and ceiling.

Similar results are also valid at “combined” occupancy duration, as long as appropriate shading devices are incorporated (demountable canopies, retractable awnings, louvers or shades).

The necessity that the interior walls and ceiling in Building 1 be repainted, led to the research of finishes which would reduce the heat absorption by the enclosing assemblies and in this way leave a greater potion of the heat for warming the air in the occupied space. Initially the walls and ceiling in one Building 1 were painted with a decorative finish which has low thermal capacity (column 4 of Table 1) – a classic thermal ceramic coating with integrated insulating agent consisting of vacuum microcapsules. The application resulted in a significant 1.6 ^oC increase of the interior surface temperature of the enclosing wall. This completely eliminated the surface condensation and mold growth, which caused the surface repainting at first place. There was also a reduction (of 3%) of the time that was required for reaching optimal indoor microclimate, and in turns reduction of energy consumption. This experiment showed very satisfactory results in terms of surface condensation and mold growth removal, however the rest of the results did not show significant improvement of the indoor microclimate and the energy savings.

During the next winter period of another but identical Building 1, a different wall and ceiling finish was applied. It was a “new generation” thermal ceramic coating which not only contained an agent with vacuum microcapsules, but a Low-e component as well (column 5 of Table 1). This coating combined both the ability to reduce heat absorption of the enclosing assemblies and reflectance of the infrared waves emitted by the heating devices. The result was a very significant reduction (of 9.5%) of the time and energy consumed for raising the air temperature of the space to 20 ^oC. The interior surface temperature of the enclosing wall was high enough that no risk of surface condensation or mold growth was present, even though it was practically lower than the measurement taken with the classic thermal ceramic coating. The test body temperature was significantly increased, which was another evidence of the infrared heat transfer in the space. Another confirmation of the effect was that the occupants can feel the warmth in the space very rapidly even at air temperature of 20 ^oC. This allowed the air temperature to be lowered to 19 ^oC during the entire winter season, without compromising the thermal comfort in the space. During the winter period of 2011 the energy consumption was 320 kWh less compared to the energy consumed by Building 1 without the application of Low-e coating on wall and ceiling surfaces. These results are fully comparable to the characteristics of “lightweight” construction type building, which in all instances is the most appropriate for episodic occupancy duration.

The measured results and conclusions made based on those results are valid for “solid” construction type buildings (Building 1), which are permanently occupied but experience significant temperature variation in the spaces during a twenty-four-hour period. In such building, reliable defense against surface condensation and mold growth could be achieved with classic thermal ceramic coatings. The “new generation” of thermal ceramic coatings provides not only condensation and mold prevention but also increased energy savings and higher quality of the indoor environment. This type of coating allows for a much greater flexibility in the occupancy duration, both episodic and permanent without compromising the overall energy efficiency of the building. This is also a great relief for designers as they don’t have to address the problems of occupancy duration too early in the design process and provides greater flexibility in the selection of building construction types and materials.

• Link to products - thermoceramic coatings

 

Remarks:
1. Experiments are carried out by a team of specialists, including the authors, in the period between 2007 and 2012 in a new residential suburb near Berlin, Germany.
2. Classic thermal ceramic coatings are available in Germany since 1999 and thermal ceramic coatings with Low-e component since 2009, including the coating used in the experiments (column 5 of table 1) . In order for the energy savings to be estimated it is appropriate to re-calculate the thermal resistance of surface heat transfer of a treated surface with the surface reflectivity values of a particular Low-e coating (Ri = 0.32 is used in the experiment with SuperShield Interior).
3. Results are valid for residential buildings at permanent occupancy duration in Nord / Central Europe because most of those are heated on demand by turning an on/off switch and the problems of surface condensation and mold growth are very common.
4. Measurement of the energy savings that Low-e coatings provide could be used as applied by the investigating team as well as with the standard methods used for thermal ceramic coatings such as ThermoShield.
http://download.dimagb.de/docs/TS/rechenwerte/R04RechenwerteThermoShieldTeil4070604.pdf

 

 

 

 

 

Pestim energia Ltd. will take place as an exhibitor in the international Exhibition 'Energy Efficiency & Renewable Energy' (EE and RES), which will take place in the framework of the 8th EE and RES Congress for South-East Europe.

The exhibition will take place in Inter Expo Centre, Sofia, Bulgaria, from 28 to 30 March, 2012. At the booth of Pestim energia Ltd. you will be able to see and receive information about the infrared heating panels InfraHEAT, the heating nano-foils, the thermoceramic insulation paints SuperShield and other innovative solutions.

We are looking forward to meet you!

Infrared panels InfraHEAT

Planning

In August 2008, despite all the debate over a national definition, a municipal real estate company decided to attempt to build a PHI Passive House in Sweden as an experiment. After thorough consideration, a research trip to Germany, and a collection of detailed information, the “first internationally certified Passive House in Sweden” project began. The architect had received Passive House training even before she began designing the building, and all other engineers and builders were trained and given support over the course of the project. The strong will shown by the real estate firm made it possible to build a kindergarten that now fulfills the PHI’s quality requirements for certification.

 

 

 

Construction

Construction began in August 2009, and except for the windows and air-tight elements, almost all products used were made in Sweden. The construction company faced the great challenge of handling new routines, products, and processes for quality assurance and cooperation. All trade workers involved in construction received training; as a result, the structure is the most air-tight building in Sweden at 0.15 h-1. The kindergarten was dedicated in September 2010. The building’s heating, humidity, indoor temperatures, and technical performance will be measured and analyzed for another two years.

 

The result

On the screen in the children theatre room, the children and their teachers can see how much energy their 'house' consumes - in this way, they can also follow how their activities affect their environment.

 

Heating demand for the kindergarten in Åkersberga has been calculated with PHPP as 14.6 kWh/(m2a). If the building were in Munich, heat demand would be cut in half. Kindergarten staff were given a user handbook at a two-hour Passive House information session, where the certificate was also presented. After the first four months of winter, energy consumption for heating was 2.1 kWh/m2 – lower than any other kindergarten in the country. The building’s comfort and quality impresses not only the users and the real estate company, but also the numerous visitors. The result has inspired other Passive House projects, such as more kindergartens and a tennis center built to the international Passive House Standard. The CEPH course has been offered in Sweden since December 2009 with more than 60 participants so far, including the architect of the country's first certified kindergarten. This training and experience with domestic Passive House projects (and the understanding for detail that these factors lead to) are key to energy-efficient construction in Sweden.

 

Banks in Bulgaria give EUR 54 million for energy saving.

 

 

The REECL facility aims to give householders or Associations of Home Owners across Bulgaria an opportunity to realise the benefits of energy efficiency home improvements by providing them with loans and incentive grants through local participating banks.

Any householder or Association of Home Owners who takes a REECL loan is entitled to receive an incentive of 20%, 30% or 35% respectively toward the cost of the energy saving project once it has been completed at their residence, subject to terms and conditions.

 

Loans and grants are given for the following energy efficiency installations:

•	Energy Efficient Windows
•	Insulation of Walls, Roofs, and Floors
•	Gas Boilers
•	Biomass Fuelled Room Heaters, Stoves and Boiler Systems
•	Solar Thermal Systems
•	Cooling and Heating Heat Pump Systems
•	Building-Integrated Photovoltaic Systems
•	Heat-Exchanger Stations and Building Installations
•	Gasification Installations
•	Balanced Mechanical Ventilation with Heat Recovery

living connect® is an electronic radiator thermostat controlled by a central unit called Danfoss Link™ CC. Communicating on Z-Wave, Danfoss Link™ CC can control living connect® thermostats, floor heating – both electrical and hydronic – and the on/off switches in a house.

Read more about the intelligent thermostats at http://www.living.danfoss.com/

 

Powerful, durable and even easier to install

Vitosol 100-F flat-plate collectors make an impression with their high efficiency and their attractive price/performance ratio. The Vitosol 100-F flat-plate collector that has been successfully used for many years now, has been further improved; its even lower weight makes it even more easy to install. High quality ensures permanent operational reliability, a long service life and high efficiency.
 
Long term efficiency

The highly selective Sol-titanium coating efficiently utilises the solar irradiation and achieves a high efficiency. The Vitosol 100-F housing comprises an all round folded aluminium frame without mitre cuts and sharp edges. Together with the seamless weather and UV resistant pane seal and the puncture proof back wall, these features ensure a long service life and long-term high energy yields. Read more about the promotion.

 

Pestim Energia Ltd. participated in the competition organised by b2b Media "The greenest companies in Bulgaria for 2010". Following the strict criteria set by the methodology of the competition, the jury announced that Pestim Energia Ltd. takes third place in the category "Technologies".

 

We are glad that our activities are recognised on a national level, and we are determined to continue working for the comfort of our clients, delivering more energy efficient heating and cooling solutions, contributing to a cleaner environment and aspiring to a more beautiful future for all of us.

 

More information on the competition, you may read here.

SuperShield Exterior Metal was applied to a roof with shingles. Special measuring equipment has been placed in order to monitor temperatures under the roof and within the house during the whole summer period. On the very first day, the temperature under the roof fell considerably. For the moment, there is no need to switch on an air-conditioner to cool the premises. The exact parameters will be published on our company website.

 

 

Global Wind Day is a worldwide event that occurs annually on 15 June. Its purpose is to promote wind energy and its contribution to the global low-carbon energy mix. Wind energy contributes in more than 75 countries and on Global Wind Day thousands of public events are organised throughout Europe and the world.

 

The European Wind Energy Association (EWEA) and the Global Wind Energy Council (GWEC) coordinate the Global Wind Day, which started as a ‘European’ day in 2007 and became a global event in 2009. Last year there were 220 events in 29 countries.

 

Global Wind Day events range from open-air theatre, kite building and kite surfing, visits to wind farms and wind industry jobs fairs. Some highlights of this year’s edition of the event include the German Technology Museum in Berlin opening its doors for a wind energy exhibition and the announcement in New York City of WindMade, an initiative to develop a consumer label for companies and products using wind power.

 

“With wind, we can achieve a genuine energy revolution, and on 15 June, people on all continents celebrate the promises that wind power holds for our planet”, stated GWEC’s Chairman Klaus Rave.

 

For further information:
www.globalwindday.org

The ultra silent fan-coils Carisma are now on the market! In line with innovative trends and modern industrial design, the Carisma fan coil range meets today’s demanding requirements of performance, size, acoustics, low energy, ease of installation and maintenance. Designed around 5 different versions, the extensive range includes wall and ceiling mounted units, exposed or concealed with either tangential or centrifugal fan options, delivering one of the most versatile ranges of fan coils on the market today. All CRC fan coils with centrifugal fans are equipped with electric motors which dramatically reduce electrical consumption of up to 40% comparative to previous models, with 6 speed motors as standard offering greater flexibility in the selection of products. New market trends have also led to an extension of the four pipe model which now has a two row LTHW battery giving improved outputs at lower flow and return temperatures. As a special option, the Carisma range can be fitted with the Crystall patented electrostatic filter featuring a class D rating according to standard UNI 11254 which equals a traditional mechanical filter of up to F9 without dramatically affecting static pressures. A full range of control options is available including the Free patented wireless control offering greater flexibility in the installation of units, with the highest precision in monitoring and maintaining the desired comfort conditions.

http://www.vesti.bg/index.phtml?tid=40&oid=3046451

SuperShield is the newest thermoceramic coating on the market. Painting with SuperShield, you acquire insulation equivalent to 3 cm EPS! Mould problems remain in the past! Read more about the product in division "Insulation".

View Telegraph pictures of eleven countries most at risk from climate change: http://www.telegraph.co.uk/earth/earthpicturegalleries/6750877/Copenhagen-climate-change-conference-countries-most-at-risk-from-the-effects-of-global-warming.html

The UN Climate Change Conference begins tomorrow, 7 December, in Copenhagen. You may also join! Sign the UN Climate Petition and become a citizen of "Hopenhagen": http://www.hopenhagen.org/ Be active and protect our environment: http://www.un.org/wcm/content/site/climatechange/pages/gateway/take-action

High efficiency from Radiatori 2000, Italy. Mounting heights 200mm, 350mm, 500mm, 600mm, 800mm, 1800mm. Technical data and prices are available in the product catalogue.

http://www.itsyoursmartgrid.com/ If you were to visualize the current grid, you might look at it as a star, with energy and information flowing in one direction from the center—from utilities to end users. The smart grid of the future will reflect the way we live today. It will act much more like an interactive web, or “energy Internet,” with two-way communication, multi-directional power flow, and closed-loop automation at its core.

The Austrian ceramic chimney systems Schiedel will be offered with a 20% discount (20% less than the price listed in the online store). The offer is valid for the period 1st Oct. 2009 - 15th Nov. 2009. 30 years warranty!

As you may already know; rainwater is repelled by lotus plants. Why? Because these plants have a natural cleaning mechanism and raindrops have almost no contact with the surface. Water droplets roll off the leaf and take dirt, insects, contaminants, water based adhesives, honey, oil and other substances with them. This phenomenon has been researched by scientist and can now be reproduced for use as nano coatings. Time and money can be saved, and cleaning agents become almost redundant. Our products are therefore recommended for all businesses with hygienic regulations, for example, food selling businesses, restaurants, cafes, butchers, abattoirs etc. Our products are, of course, also recommended for private use to protect all sorts of things against contaminants or weathering and to save time and money on the use of cleaning agents. Advantages: Nanotechnology - Lotus Effect: A Fully tested highly effective product, providing long lasting protection. Treated materials are not visually changed and remain suitable for whatever their original designated use. Protection against aggressive environmental impacts, weathering and scratches. Surfaces and all sorts of textiles are easier to care for. Longer lasting cleanliness; visually and hygienically, antibacterial, easy cleaning, neutral to skin, non-allergenic etc. All that and easy handling make nano coatings ideal for all different areas. If the repelling effect decreases, it's probably something to do with soiling. In that case, clean the surface or textile with a mild cleaner and wash off thoroughly. Afterwards the repelling effect will be reinstated (with textiles after drying). If the coating is actually damaged, the surfaces can easily be retreated. Arguments, that speak for themselves: * Antibacterial * Easy cleaning * Easy handling * Harmless to food * Easier to care for textiles * Completely neutral to skin * Easier to care for surfaces * Anti-adhesive characteristics * Protection against scratching * Protection against weathering * Longer lasting cleanliness, visually and hygienically * Treated materials remain suitable for whatever their original designated use. There are even more advantages with nano coatings and when used once you will never want to be without it !

For news related to the company Pestim energia Ltd., please, follow the company website link.