Category Archives: EuroSun2008-4

Renovation concepts for saving 75% on total domestic energy consumption

F. G. H. Koene 1* and B. Knoll 2

1 Energy research Centre of the Netherlands ECN, Department of Energy in the Built Environment,

P. O. Box 1, 1755 ZG Petten, The Netherlands

2 TNO Building Research, P. O. box 49, 2600 AA Delft, NL
Corresponding Author, koene@ecn. nl

Abstract

In the RIGOUREUS project, ECN, TNO, TU Delft end DHV cooperate to develop innovative and affordable renovation concepts for terrace dwellings in The Netherlands, aiming at reducing their total (primary) energy consumption by 75%. A key aspect in the realisation of this target is minimisation of heat losses and maximisation of using solar heat. The basis for the concepts to be developed therefore is the Passive House concept and a solar collector in combination with additional measures.

The potential of integral renovation concepts based on maximising the amount of passive and active solar energy is explored, addressing the reduction of space heating and DHW as well as the reduction of domestic electricity consumption. A number of additional measures are presented, in particular aimed at decreasing electricity consumption in order to achieve the energy target.

Keywords: Renovation, 75% reduction primary energy, integral concept.

1. Introduction

The energy consumption in the built environment accounts for approximately one third of the total energy consumption in The Netherlands. The introduction of the Energy Performance Coefficient EPC in The Netherlands in 1998 as a mandatory requirement for new buildings has contributed considerably to the reduction of the energy consumption of new dwellings. However, little effort has been undertaken so far for existing buildings in this respect.

In the RIGOUREUS project, ECN, TNO, TU Delft and DHV develop innovative renovation concepts aiming at a reduction of 75% of the total (primary) energy consumption for Dutch terrace dwellings. A key aspect in the realisation of this target is minimisation of heat losses and maximisation of the solar contribution, while reducing the building related and user related electricity demand. The basis for the concepts to be developed is the Passive House concept [1], minimising the energy demand for space heating, in combination with a solar thermal collector to reduce the energy demand for DHW. Even though these concepts are well known in German speaking countries, several factors have prevented widespread application in the Netherlands, such as: fear of the unfamiliar, the typical Dutch building practice and economical considerations. Nevertheless, it is regarded as a necessary starting point for energy ambitious renovation concepts.

Different faces of the sun

“The sun has two different faces. The kind face of the sun appears in cold times; and its unkind face appears in hot times. In according to the properties of each location, kind and unkind faces of the sun differ from place to place, these local faces of the sun more than whatever depend on two parameters: 1st, the intensity of direct and diffused solar radiation in each moment; 2nd, the amount of need to shade or shine in according to the difference between comfortable temperature and outdoor temperature in each moment. [1, 61-91] & [2,1]”

image165

Fig. 2. Defining kind and unkind faces of the sun (desirability/undesirability of direct radiation) in the city of Yazd[31.5N, 54.2E] using 21°C as the base: 0.01 * radiation received x (21°C — outdoor temperature)

*

However other parameters such as wind and humidity have important roles in comfort condition, we decide not to apply them here to see the major effect of parameters of position of the sun, its total radiation and the changes in temperature through the day and in each month.

image166

Fig. 3. Different faces of the sun in different cities of Iran

 

In Ramsar[36.9N, 50.7E] cloudy weather and low changes in temperature from the sunrise to the sunset and through the year is the reason why the level of kind and unkind faces of the sun is low. Hamedan[34.8N, 48.6,E] and Tabas[33.6N 56.9E] are almost on the same latitude but Hamedan has cold climate and Tabas is hot. Shiraz[29.7N 53E] has two hot and cold conditions so in this city the kind and unkind faces of the sun has high levels.

*

Introduction to optimal ADS handling for LESO occupants

Last but not least, some problems occurring within the examined ADS-equipped offices could be avoided by giving a short introduction on optimal ADS handling to some office occupants. Some of the problems revealed during this study (e. g. occupants feeling that their office is too dim or that they cannot find an appropriate lighting configuration) are indeed often the result of inadequate ADS handling.

2. Conclusion

Подпись: <u "я <u о Я я о Я я я я я <и Подпись: Office seems Glare Too much Too much Office seems Glare too bright. problems. light on daylight in too dim. problems workplane. office. difficult to handle.

This study clearly shows that the ADS installed within most offices of the LESO-SEB are in general very well accepted by the building’s occupants. There are, however, some issues that should be taken into consideration when installing ADS in other buildings. Our study has revealed that most of these problems are caused by temporary daylight overprovision within the offices. Figure 5 gives an overview of the main problems and quantifies how annoying these problems are to the occupants.

Figure 5: Overview of the main lighting related problems within the examined ADS-equipped office rooms. Annoyance values are in general quite low, and most problems are due to temporary daylight-overprovision, resulting from inappropriate blind configuration and blind control as well as problems with ADS handling.

It can be concluded that the annoyance of most problems revealed during our study could be drastically reduced by optimizing the blind configuration and the blind control as well as by giving introductions on how to properly handle the ADS to the building’s occupants. These findings can be of great interest to architects and engineers who plan similar systems for other buildings in the future.

References

[1] Wittkopf, S. K., Yuniarti, E. and Soon, L. K.: Prediction of energy savings with anidolic integrated ceiling across different daylight climates. Energy and Buildings 38, pp. 1120-1129, 2006.

[2] Scartezzini, J.-L. and Courret, G.: Anidolic daylighting systems. Solar Energy 73, pp. 123-135, 2002.

[3] Welford, W. T. and Wilson, R.: Non-Imaging Optics. Academic Press, New York, 1989.

[4] Courret, G., Scartezzini, Jean-Louis, David Francioli, D. and Meyer J.-J.: Design and assessment of an anidolic light-duct. Energy and Buildings 28, pp. 79-99, 1998.

[5] Courret, G., Scartezzini, J.-L.: Systemes anidoliques d’eclairage naturel. PhD thesis, Ecole Polytechnique Federale de Lausanne (Switzerland), 1999.

[6] Linhart, F. and Scartezzini, J.-L.: Efficient lighting strategies for office rooms in tropical climates. In PLEA 2007, pp. 360-367, Singapore, 2007.

[7] Altherr, R. and Gay, J.-B.: A low impact anidolic facade. Building and Environment 37, pp. 1409-1419, 2002.

[8] Eklund, N. H. and Boyce, P. R.: The development of a reliable, valid and simple office lighting survey. Journal of the Illuminating Engineering Society, v 25 n 2, pp. 25-40, 1996.

[9] Akashi, Y. and Boyce, P. R.: A field study of illuminance reduction. Energy and Buildings 38, pp. 588­599, 2006.

[10] Ramasoot, T. and Fotios, S.: Lighting for the classrooms of the future. In Lux junior 2007, Dornfeld, 2007.

[11] Gavin, G. and Deschamps, L.: Domotique — Configuration et installation d’un micro-serveur KNX « MyHomeBox ». Diploma project, EPFL, 2008.

Thermal Performance and Modelling

During the construction of the house, more than 120 thermocouples and other sensors (e. g. electricity meters, etc.) were installed for thermal performance and energy-efficiency assessment. “T” type constantan copper-nickel thermocouples with accuracy of 0.5 °C are used.

1.1. Space heating energy consumption

The envelope of the house is well insulated. Windows are triple glazed with two low-e (emissivity 0.35) coatings and 13 mm Argon-filled gaps. They have an effective thermal resistance of RSI 0.8. The solar transmittance of the windows is 36% and the visible transmittance 71% at normal incidence. The total south facing window area of the ground floor is about 13 m2, which is approximately 15% of the ground floor area. The average effective RSI values for the walls above grade and roof are RSI 6 and RSI 8, respectively. The basement walls have a thermal resistance of

RSI 4, while that of the basement floor is RSI 1.5. The wall thermal resistance values were selected following a sensitivity analysis with the building simulation software HOT2000 [9].

Currently, the house is reserved for monitoring, and sometimes public visiting, so it is not occupied. The space heating consumption recorded will be over-estimated due to the absence of internal heat gains (e. g. appliance and human body). However, with the comparison of the data between cold sunny days and cold overcast days, we can see the contributions to the reduction of space heating energy consumption from passive solar heating. For three continuous days (Fig. 2), during which BIPV/T and ventilated slab did not operate, the heating requirement was 78 kWh for Jan.12th, 60 kWh for Jan. 13th, and 96 kWh for Jan 14th. The average outdoor temperature of Jan. 12th is 5 °C higher than that of Jan. 13th, which was sunny. Another graph (Fig. 3) for Feb. 24th, a perfect sunny day, shows that passive solar space heating and small contribution from BIPV/T heating is able to bring the room temperature 4 °C higher (from 21 °C heating setpoint to almost 25 °C) during the day time even though average outdoor temperature was around 0 °C. The thermal energy stored was adequate to keep the room air temperature above setpoint until 3:00 am of the next day when night-time outdoor temperature was around -5 °C.

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Fig. 2. Temperature and solar radiation profiles for three mild cold winter days.

 

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Fig. 3. Temperature and solar radiation profiles for two cold winter days.

 

1.2. BIPV/T system

The system was designed to cover one continuous south-facing roof surface for aesthetic and improved roof hygrothermal performance. A 3 kW PV system was installed in the house. It consists of 22 Unisolar PVL-136 laminates attached to the metal roofing (each panel is rated at 136

Подпись: Building Подпись: Back Подпись: Top

W for a total of 22×136 W = 2992 W). The electricity generated by the BIPV system as determined by RETScreen [10] is 3420 kWh/yr for a 30° slope. A gap is created between the metal roofing and the sub-layer behind them as shown in Fig. 4. Outdoor air is used as the heat transfer fluid in an open loop system so as to keep the temperature of the PV panels as low as possible, thus increasing their electricity production. Solar-heated BIPV/T air is used for domestic hot water heating, clothes drying, or VCS thermal mass heating in order of priority.

Fig. 4. Thermocouples measuring back surface, air, and top surface temperatures at different sections.

Air temperatures are measured at all the 6 locations indicated in Fig. 4. Top surface temperatures are measured at all locations except location 1. Back surface temperatures are measured only at location 2, 3, 4, and 5. The thermocouple for top surface temperature is fastened on the nearby wood framing surface. When the top surface (metal sheet) is installed on the roof, the thermocouples firmly touch the top surface.

Solar plants installed

Within the “Solar Jails” programme, two solar thermal plants have been installed yet. They are operating respectively into the Jail of Rebibbia (Rome) since 2002, and into the Jail of Terni (about 120 km north of Rome) since summer 2008.

In the framework of the first “Solar Jail” project, 96 flat — plate solar thermal collectors have been installed with a total useful area of 250 m2 (175 kWth) in order to contribute to the preparation of 18,000 l/day of DHW at 45 °C, for 400 prisoners. The plant, designed to perform a solar fraction of about 60% of the DHW annual demand, was installed with the support of 10 prisoners previously trained on solar thermal. Currently, prisoners are also involved in maintenance and in data acquisition.

Thanks to this first pilot experience, many of the problems faced during either the system operation or the implementation of the general procedures have been already solved, and several improvements carried out in the second phase of the programme.

image343

Fig. 1. Prisoners working on first Rebibbia solar thermal plant.

Concerning the new plant in Terni, 60 flat — plate solar thermal collectors have been installed with a total useful area of 156 m2 (109 kWth).

The average daily consumption of 350 users is around 13,500 l/day, at 40 °C. The solar thermal system is expected to supply the 70% of the estimated total annual energy request, that is 208 MWh per year. Therefore, the annual solar output foreseen is about 146 MWh.

image344

Fig. 2. Solar thermal plant in Temi’s jail: solar thermal collectors (on the left) and storage tanks (on the right).

The plant is endowed of a monitoring system for gathering all the parameters needed to control the energy performances of the plant, the operating temperatures and the achievement of the solar results. Furthermore, in the next future, it might be possible to store the data collected (in different sites) in a central database.

A second plant is now under construction in Rebibbia Jail, where 180 m2 (126 kWth) flat — plate thermal collectors are expected to deliver 110 MWh per year to 396 prisoners. Five more systems are foreseen to be carried out within the 2009 in Florence, Turin, Laureana di Borrello (Reggio Calabria), Viterbo and Velletri (Rome).

3. Conclusions

Jails, not only in Italy, are usually located in buildings with large surfaces suitable for installation and without strict aesthetical requirements for the architectonic integration. Those characteristics, coupled with the very high and continuous annual DHW energy demand, show clearly the huge potential for the repeatability of this initiative.

The main outputs expected by the completion of this phase of the “Solar Jails” programme are:

• empowerment and new reemployment opportunities for about 250 prisoners trained as solar thermal

installers;

• 15 new large scale solar thermal plants, i. e. up to 3,750 m2 (2.6 MWth) of solar thermal collectors

installed;

• energy costs savings for jails to be reinvested in activities and infrastructures;

• staff of public technical departments skilled in solar thermal to secure the project durability and to act

as multiplier in other public buildings;

• improvement of knowledge on the behaviour of solar thermal plants.

References

[1] A. Corrado, R. Battisti, A. Micangeli, (2002), Large Scale Solar Thermal Plant For Domestic Hot Water In The Italian Rebibbia Jail, Proceedings of the EuroSun 2002 Conference, 23 — 26 June 2002, Bologna, Italy

Grain size measurements

Grain size can be measured using any of the methods outlined in (a) to (e) above. The first two methods (a) and (b) are comparism methods and give results that are within plus or minus a whole grain size and so are not very accurate. The last two methods (d) and (e) are direct measurements but they also give inaccurate result. This is because their parametric reference is just a straight line which when drawn and juxtaposed against a micrograph may lead to much error in counting the number of grains intercepted by the line. At best, therefore, they can only give single parametric description of the grains. This leaves us with that of the planetric Jeffries method (i. e method (c) for the grain size measurement.

This method provides a single number estimate of all the parametric description of grain size mentioned in the introduction. Hence it provides a full description of grain size, which can be used for any structure — property correlation [2]. Before describing the method, it is necessary to present some definitions of grain sizes, which will help us to understand the Jeffries method [1, 2, 2].

Effectiveness of active solar space heating system in the dense housing area

Y. HIGUCHI1* and M. UDAGAWA2

1Visiting researchers of Kogakuin University. 1-24-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo, 163-8677

higuchi. yoshiki@kurashi-desgin. jp
2Dept. Architecture, Faculty of Engineering, Kogakuin Univ.

1-24-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo, 163-8677
udagawa@cc. kogakuin. ac. jp.

Abstract

The effect of the passive solar heating of a single family house built in the dense housing area was examined using the simulation program EESLISMver6. The EESLISMver6 is extended version of a generalized building energy and environment simulation tool EESLISM which has been developed by the authors. EESLISMver6 can take into consideration the shadow effects of trees and adjacent buildings. Daily total incident solar radiation for the house in city areas was decreased by 90% or more compared with the house without adjacent buildings, so that, heating load increased by 1.5 times against the base case. Therefore, the active solar heating system is expected for the low-rise house in the dense housing to compensate the decreased passive solar effect.

In this study, the total effect of solar space heating with active and passive ways are examined using the detailed system simulation. The simulation results show that active solar space heating system is especially effective in the dense housing area as expected in this study.

Keywords: solar space heating, adjacent building, heat load, simulation

1. Introduction

When considering the energy saving of residential houses, it is effective to use the solar radiation from windows for passive heating in winter. When a site for single family house is narrow, the enough incident solar radiation from the windows can not be expected due to the shadow by adjacent buildings, trees, etc. Moreover, curtain is generally closed in the daytime for privacy. Therefore, in order to realize energy saving and a comfortable life, use of active solar space heating is especially important for a house built in the dense housing area. It is because the interior of a room can be heated if there is even an incident solar radiation to a roof even when there is little incident solar radiation on windows.

In this study, the total effect of solar space heating with active and passive ways are examined using the detailed system simulation with a generalized simulation tool EESLISM ver6 [1] which can take into consideration the shadow effects of trees and adjacent buildings developed by the authors[2-4].

Solar Hot Water Systems in Architecture

As it is known, the aesthetical evaluation of the building depends on integrity and completeness of the appearance of the buildings that is constructed by properties of like mass, facade elements form, color and pattern features. So solar hot water systems effects the appearance and form, consequently the aesthetic of the building because of the efficiency needs of slope and orientation and the surface properties of collectors like color, texture and dimension. [1] Therefore, the evaluation of systems as an architectural component and consideration of aesthetic with efficiency and economy as a fact in system design have great importance for a healthy system-building relationship.

Подпись:
Today, in the context of sustainable construction the applications, that evaluates systems, as a part of the building as an aesthetical component beyond their benefit rises, on the other hand the existing solar hot water systems are still effecting the building and the city negatively with their ugly appearances in many countries.

This problem is composed of natural convention — open circulated annex systems, which users apply individually at the top of flat roofs for their specific needs, without consideration of integrity, completeness and harmony with the building. As these systems, don’t need major modifications on buildings, have simple constructions and low costs they have wide spread usage and mostly they are being manufactured and applied without any control which causes to

• Ugly appearance of the buildings,

• Low efficiencies,

• Unhygienic conditions,

• Visual pollutions and corruption of the aesthetic view in cities.

These complications, makes solar hot water systems a problem that has to be solved in concern of architecture and urban beyond their benefits and advantages. [2]