S LAR UPDATE NEWSLETTER OF THE INTERNATIONAL ENERGY AGENCY SOLAR HEATING AND COOLING PROGRAMME • NO. 35 DECEMBER 2000

Solar Combisystems for a Future

ince December 1998, 25 experts and 11 solar industries , and , the demand for solar com- from 9 countries have been collaborating to further devel- bisystems is increasing rapidly (see figure 1). Sop and optimize solar combisystems for detached single- family houses, groups of single-family houses and multi-family houses. This project, which is part of the Solar Heating and What is a Combisystem? Cooling Programme, is working to standardize the classification Solar combisystems are solar heating systems for combined and evaluation of solar combisystems with the overall objective domestic hot water preparation and space heating. They are sim- of developing recommendations for the international standard- ilar to solar water heaters in that they use and trans- ization of combisystem test procedures. port the produced heat to a storage device. The major difference is that the installed collector area is generally larger for com- bisystems, as there are two heat loads to meet. Also, a combisys- Why Solar Space Heating? tem uses at least two energy sources to supply hot water and Throughout the world, hundreds of thousands of domestic solar heating—a solar collector and an auxiliary energy source. The hot water systems are demonstrating the possibilities of this auxiliary energy source could be , gas, oil or electricity. source. Due to the success of these hot water The key design challenge is how to integrate the different systems, more builders are turning to solar energy for space requirements of the heating source and the heating loads into a heating. The heating requirements of a single- or multi-family single, cost-effective, durable and reliable heating systems while dwelling can be met at acceptable costs by combining solar heat- achieving the most benefit from each installed square meter of ing systems with short-term heat storage and well-insulated collector. buildings. And in several European countries, such as , The complexity of solar combisystems has led to the devel- opment of a large number of different system designs. These designs do not necessarily reflect local climate or practice. For IN THIS ISSUE example, several systems on the market can be used in a variety of geographical locations. It is for Solar Combisystems this reason that collaborative work for a Sustainable to analyze and optimize combisys- Energy Future tems is important if these systems 1 are to reach a more wide spread market. Advancing Daylighting Technologies and How Combisystems Can Daylight Conscious Contribute to a Cleaner Environment Building Design The increasing concentration of 4 greenhouse gases in the atmo- sphere and the potential global MarketPlace warming and climatic change asso- 7 ciated with it, represent one of the greatest environmental dangers of New Publications our time. The reason for this 6 Solar combisystem provides 60% of the space heating demand to six terraced impending change in the climate In Brief houses in Austria. (Source: AEE) can, for the most part, be attributed 5 continued on page 2

1 Solar Combisystems Share of Solar Combisystems in Selected Countries - 1997 continued from page 1

to the combustion of fossil fuels and the associated emission of )s 2 CO2. The effective protection of the climate, according to many experts, will require at least a 50% reduction in the anthro- pogenic emission of greenhouse gases over the next 50 years. As a result of the climate conferences over the last decade and the discussions on sustainable development, the European Commission has set goals for the future development of renew- able energy sources in the White Paper “Energy for the Future: In 1997 Installed collect or area (m Renewable Sources of Energy.” In the Commission’s White Paper the following is mentioned as a strategic goal: “... to increase the market share of renewable sources of energy to 12% by the year 2010.” The White Paper estimates that a 20% annual increase in the installed collection area in EU countries Figure 1. Installed combisystems and collector area for 1997 in selected countries. is needed. Thus, solar heating systems in operation in the year 2010 would correspond to an overall installed collector area of 100 million m2 (see figure 2). Increase in the installed collector area in the EU If solar heating is to make a relevant contribution to the energy supply then solar technologies that do more than domes- tic hot water preparation must be developed and widely dis- tributed. A realistic approach would be to assume that in the next ten years about 20% of the collector area installed annually in the European Union would be used for solar combisystems. This means that EU countries would need to install approxi- mately 120,000 solar combisystems with 1.9 million m2 of col- lector area per year. Million Square Meters

Combisystem Designs The solar contribution of combisystems varies from 10% up to 100% depending on the size of the solar collector surface, stor- Figure 2. Installed collector area goals until 2010 in European Union member age volume, hot water consumption, heat load of the building, countries. and climate. As mentioned before, there are a variety of systems ) 2 Solar Radiation (W/m

Solar combisystem for a single-family house in . (Source: SERC) Figure 3. Solar radiation on a horizontal plane in Zurich, Switzerland.

2 on the European market. The difference Solar Energy in the systems is partly due to the condi- Availability tions prevailing in the individual coun- Installed systems clear- tries. For example, the “smallest sys- ly show that solar space tems” in terms of collector area and stor- heating is possible even age volume are located in those countries under mid- and northern where gas or electricity is primarily used European climatic con- as the auxiliary energy source. In the ditions. The solar ener- Netherlands, for instance, a typical solar gy available in summer combisystem consists of 4-6 m2 of solar is more than twice that collector and a 300 litre storage tank, and available in winter, therefore, solar energy meets a relatively which is practically the small share of the heating demand. opposite of the demand In countries such as Switzerland, for space heating. Austria and Sweden where solar com- Unlike hot water prepa- This French house uses a solar floor to meet hourly and bisystems are typically coupled with a ration, the heating load overnight variations in the solar energy supply. (Source: Clipsol) biomass , larger systems with high is dependent upon the fractional energy savings are installed. outside temperature. Measurements of ing) or the storage mass of the Common systems for a single-family solar radiation and temperature in the building. house consist of 15 m2 up to transitional periods ■ If little or no solar radiation is avail- 30 m2 of collector area and a (September-October and able for several days, a small buffer 1-3 m3 storage tank. The March-May) clearly show storage volume can be used to make share of the heating demand The solar that solar radiation avail- up the difference in solar radiation. In met by solar energy in these contribution of ability is relatively high at this case, heat storage may be com- systems is between 20-60%. combisystems varies the beginning and the end of bined with domestic hot water storage In contrast to the Dutch sys- from 10% up to the space heating season. or an additional storage tank used for tem described above, which Even on winter days, energy hot water. uses DHW to store heat for 100% depending on demand and solar radiation ■ Seasonal variations in the solar energy subsequent delivery to the the size of the solar are partially related. supply can only be compensated for space heating loop, these collector surface, Figure 3 shows the by using seasonal storage. Several systems store heat for space storage volume, hot solar radiation on a horizon- systems show that it is possible to heating in the water of the tal plane in Zurich, Switzer- store summer heat in large water space heating loop itself. water consumption, land. It can be seen that, reservoirs (60 -130 m3) for use later In addition to systems heat load of the under this latitude, there are on in winter. Systems in Sweden, for one- or two-family hous- building, and not only strong seasonal Denmark and Germany provide inter- es, there are systems for climate. variations in radiation esting examples. multi-family houses and ter- throughout the year, but that raced houses. These larger solar radiation varies widely For more information on this Task con- systems also have shown promising on a daily and even hourly basis. tact Werner Weiss, SHC Task 26 Operat- results over the years. In Gleisdorf, Aus- In order to make efficient use of the ing Agent, e-mail: [email protected] and tria, a system was installed in 1998 for an available solar energy supply, it is neces- fax: +43-3112-588618, or visit the SHC office building and six terraced houses. sary to even out the fluctuations using web site. The collectors have been integrated into storage systems so that hot water can be A colored brochure, "Solar the roofs of the winter gardens and cover supplied continuously and a constant Combisystems in Austria, Denmark, Fin- 80% of the hot water and 60% of the can be guaranteed. To land, France, Germany, Sweden, Switzer- space heating demand. The remaining balance out the variations in energy sup- land, the Netherlands and the USA Ð energy needs are provided by a biomass ply and demand, the following options Overview 2000," can be ordered from: boiler, and a local heating network that are available: Büro n+1, Postfach 130, CH-3000 Bern connects the houses to the central 14 m3 16, e-mail: [email protected] and fax: +41- storage tank. ■ Hourly or overnight variations can be 31-3527756.✷ compensated for by the inertia of the heat emission system (e.g., floor heat-

3 Advancing Daylighting Technologies and Germany Daylight Conscious Building Design

An international col- Denmark laborative effort to advance daylighting technologies and to promote daylight con- scious building design was jointly undertaken by the experts of the Solar Heating and Cooling (SHC) Programme and the in Buildings and Community Systems (ECBCS) Programme. A secondary school in Zehdenick, The experts of the SHC and ECBCS Germany achieves 66% energy savings Programs set out to promote daylight con- in the winter and 98% savings in the scious building design in IEA countries. summer. This four-storey building has Recognizing the importance of this work, an atrium with fixed angled that industry was actively involved as well as lights the stairwells and halls. The class- design practitioners and consultants. This The Bayer Nordic headquarters in Copenhagen, Denmark rooms are daylit from windows on the achieves 23% energy savings in the winter and 92% savings in the south-west facade and clerestorey win- diverse and knowledgeable group of summer. This L-shaped building has an atrium that extends dows facing the atrium. External shades experts worked for four years to achieve throughout the entire length of the building. In each office daylight protect the windows from high incidence their objectives. enters two daylight windows and two vision windows which use sunlight while internal semi-translucent To narrow the scope of their work, integrated tilting blinds. Daylighting and occupancy sensors are blinds are used to decrease glare. the experts focused on daylighting sys- used to control the artificial lighting. tems and strategies that could be applied in new and existing buildings with a high aggregate electricity saving potential, such United States Germany as offices, schools, and commercial and institutional buildings. The experts tested systems and strategies and conducted per- formance assessments in laboratories and case study buildings as well as with com- puter simulations. These assessments covered visual, architectural and environ- mental aspects, including user acceptance of the systems. A conclusion of this work is that although the future will bring new techno- logical daylighting concepts to the market, many of the current limitations will The National Renewable Energy Laboratory’s The Götz office building in Würzburg, Germany remain. Therefore, manufacturers and Solar Energy Research Facility in Colorado, United achieves 77% energy savings in the winter and 91% building designers will need to accept this States has achieved a 75% increase in energy sav- savings in the summer. This two-storey building has a fact so that daylighting systems can be ings. This building combines two-storey research completely glazed double facade and a center atrium successfully applied. laboratories with single-storey offices. The primary with a sliding roof. Integrated reflective and absorp- The following are examples of the 15 daylighting elements are a stepped roof form with tive shading louvers are used to control the solar buildings monitored in Australia, Canada, lightshelves over a large open floor space. loads and the daylight. Daylighting and occupancy Denmark, Germany, New Zealand, Occupancy sensors, solar-control films on the win- sensors are used to control the artificial lighting and Switzerland, United Kingdom and the dows, and motorized window shades all contribute the louvers. United States, including the electricity to the building’s energy efficiency. savings they achieved using different day- lighting technologies.

4 TASK 21 IN BRIEF HIGHLIGHTS

■ Established international proce- dures for evaluating the perfor- mance of conventional design solutions and innovative day- lighting systems and the perfor- mance of daylight responsive lighting control systems.

■ Established international proce- dures and protocols for monitor- ing the daylighting performance New Work Underway account occupant response, and 3) trans- of real buildings including the ferring the knowledge gained to building assessment of users’ opinion of Task 22: Building Energy Analysis design professionals, building owners their working environment. Tools and manufacturers. This new Task also This Task has been extended for two will include continued work on design ■ Wrote a comprehensive source years so a comprehensive and integrated tools developed in SHC Task 21/ECBCS book on daylighting systems and suite of building energy analysis tool Annex 28, such as ADELINE, Leso- components providing an tests can be created. This suite of analyt- DIAL and DELight. overview of the main technolo- ical, comparative and empir- gies for enhancing penetration or ical methods will be used to improving distribution of day- provide quality assurance Whole Building light in workspaces. during tool development The SHC Sustainability and Tools and certification of tools for Programme A meeting was held October ■ Conducted a survey of actual energy standard or code 2000 in the Netherlands to design solutions in buildings compliance. The results continues to begin the process of defining throughout IEA Member coun- from this work will include the work in this proposed tries. 1) a revised, expanded and initiate new work new Task. Thirty-two tested working document of experts (buildings owners, ■ Developed a series of user- analytical solutions, 2) a to demonstrate tool developers and users, friendly daylighting design tools, comprehensive and integrat- and government officials) from simple tools to be used in ed suite of Envelope and the power from 12 countries attended the early design stage to HVAC BESTEST cases for the meeting. The proposed advanced tools to be used when tool evaluation, and 3) a of solar. objective of this new work is detailed design decisions are comprehensive and integrat- to accelerate the transition to made at the end of the process. ed set of experimental data a more sustainable built for the empirical validation environment, both new and ■ Conducted a comprehensive of tools. existing, through improved monitoring program to evaluate information, methods and tools. The the energy and daylighting per- Task would be divided into three sub- formance of 15 case study build- Task 31: Daylighting Buildings in the tasks which would focus on 1) defining ings. 21st Century the context and market needs, 2) defining This work is in the Task Definition and developing indicators (e.g., regula- Phase. The proposed objective to make tions, performance, targets, benchmarks, daylighting the typical and preferred weights, labels) to describe sustainabili- For more information on SHC Task design solution for lighting commercial ty, and 3) defining key problems faced 21/ECBCS Annex 29, Daylight in Build- buildings. This will be accomplished by by tool developers. ✷ ings, visit the SHC web site. ✷ 1) determining the impact of occupant response, 2) integrating advanced day- lighting systems, electrical lighting and shading controls while taking into

5 NEW PUBLICATIONS

The SHC Programme has published several new reports and software. These reports document results from work on solar air systems, solar energy use in large buildings, daylighting and solar building renovation.

Examples of Integrated Design: Five ADELINE 3.0 Software Package Low Energy Buildings Created and Brochure Through Integrated Design This software is an integrated lighting design computer tool that provides archi- This booklet showcases five buildings tects and engineers with accurate infor- selected from 21 buildings which demon- mation about the behavior and the perfor- strate how integrated design can create mance of indoor lighting systems. Both attractive, sustainable buildings. The natural and artificial lighting problems Solar Air Systems—Built Examples story of each building describes how the can be solved in simple rooms or com- The purpose of this book is to share the design team managed the design process, plex spaces. Innovative and reliable experiences from 35 building in wide traces the work flows and relations results are produced by processing data ranging climates. Applications include between the participants in the team, and to perform light simulations and to pro- single-family houses, apartment build- shows how the work resulted in sustain- duce comprehensive numeric and graphic ings and commercial buildings. Six dif- able construction. information. ferent types of solar air systems are cov- To order contact: Gerelle van To order contact: Hans Erhorn of ered. Cruchten, Damen Consultants, e-mail: Fraunhofer Institute of Building Physics, To order contact: James & James [email protected] and fax: +31 e-mail: [email protected] and fax: (Science Publishers) Ltd, e-mail: 26-351-1713. +49-711-970-339. Software cost: EUR [email protected] and fax: +20-7387-8998. 500. Cost: US$ 75. Solar Renovation Demonstration Projects: Results and Experiences Solar Heating and Cooling 2000 Solar Air Systems—A Design This booklet summarizes the major find- Annual Report Handbook ings of 14 demonstration projects that The annual report provides detailed This book guides architects and engi- integrated solar concepts into their buil- information on program activities and neers through the process of designing ing renovation. It includes a list of rec- task accomplishments during 2000. The and selecting one of the six active solar ommendations for future work in this feature article is on Solar Cities. systems presented and optimizing that area. To order contact: SHC Executive system. Tips also are given on construc- To order contact: James & James Secretary, see back page for address. tion and how to avoid problems. (Science Publishers) Ltd, e-mail: Cost: US $20. To order contact: James & James [email protected] and fax: +20-7387-8998 (Science Publishers) Ltd, e-mail: [email protected] and fax: +20-7387-8998. A CD-ROM with Task demonstra- Cost: US$ 75. tion buildings and building details also is available. To order contact: SHC Executive Secretary, see back page for address.

6 MARKETPLACE $$$$$$$$$$$ Thanks To... Conny Rolén who served as the The Solar Heating and imately 5 meters wide during a 9-hour Swedish Executive Committee Cooling Programme is work day compared to the same lighting member and as Vice-Chair. The not only making system without daylight responsive con- Committee appreciates his contribu- strides in R&D, but trols. Daylight responsive controls are tions to the work of the SHC Pro- also impacting the used in new office buildings in many gramme and efforts to facilitate col- building sector. This European countries. It is estimated that laboration between the SHC Pro- section of the newsletter highlights solar such controls are now installed in 30% of gramme and the ECBCS Pro- technologies which have been developed all the new office buildings in Europe. gramme. Michael Rantil, also or conceptualized in a SHC Task and are Task experts also found that the dif- from the Swedish Council for now being commercially manufactured, ferences in energy savings between the Building Research, is once again marketed or used. different types of daylight responsive serving as the Swedish representa- controls were minimal. Instead, control tive. The Executive Committee was systems were selected based on how happy to welcome Michael back to Daylight Responsive Lighting much the user (occupants or building the Programme and elected him Control Systems owner) could adjust the controls and Vice-Chair at his first Executive Daylight responsive controls for lighting whether the system could be integrated Committee meeting. have been on the market for quite some with other building management func- time, but with limited use. To increase tions. Katsuhiko Masuda who served as their use, lighting industries, researchers The results of this work are detailed the Japanese Executive Committee and consultants worked together in SHC in the report, Application Guide for Day- member. Minoru Yonekura, direc- Task 21/ECBCS Annex 29, Daylight in light Responsive Control Systems. The tor of MITI’s Renewable Energy Buildings, to analyze the functional and first section of this guide describes the Technologies/ Systems, will replace practical aspects of lighting controls. different types of systems, gives guid- him. This collaborative work has led to the ance on the selection, installation, eco- improvement of products and produced nomics, maintenance and user aspects. Kjeld Johnsen who served as the detailed information on energy savings The second section shows a number of Operating Agent for Task 21, Day- and user acceptance. practical cases, with results from energy light in Buildings. Kjeld has the Task results show that properly measurements and user surveys. This distinction of successfully running installed systems can save 30-50% in report will be available on CD-ROM in one of the Programme’s largest electricity costs in offices spaces approx- early 2001. ✷ Tasks. The Executive Committee congratulates him on his dedication and valuable work.

Solar Energy Activities in IEA Welcome To... Countries – 1999 Portugal the newest country to join This publication reports on the status of the SHC Programme. João Farin- solar energy activities in countries partic- ha Mendes of INETI will serve as ipating in the SHC Programme. An the first Portuguese Executive Com- overview chapter provides a summary of mittee representative. the national activities and key trends in solar building technology policies and Simon Hayman of the University programs. Data also is provided on gov- of Sydney who will serve as the ernment funding for solar energy pro- Task Organizer for new daylighting grams, government incentive programs work, Task 31, Daylighting Build- for solar technologies and solar commer- ings in the 21st Century. This Task cial activities. will continue the daylighting work of Task 21, Daylight in Buildings. To order contact: SHC Executive Secretary, see back page for address. Cost: US$ 30. ✷

7 IEA Solar Heating and Cooling Programme The International Energy Agency was formed in 1974 within the framework of the Organization for Economic Cooperation and Development (OECD) to implement a program of international Member Countries and energy cooperation among its member countries, including collaborative research, development Executive Committee Members and demonstration projects in new energy technologies. The 21 members of the IEA Solar Australia Prof. J. Ballinger Heating and Cooling Agreement have initiated a total of 29 R&D projects (known as Tasks) to Austria Prof. G. Faninger advance solar technologies for buildings. The overall program is managed by an Executive Belgium Prof. A. De Herde Committee while the individual Tasks are led by Operating Agents. Canada Mr. D. McClenahan Denmark Mr. J. Windeleff Task 25: SolarAssisted of European Current Tasks and Operating Agents Buildings Commission Dr. G. Deschamps Dr. Hans-Martin Henning Germany Dr. V. Lottner Task 22: Building Energy Fraunhofer Institute for Solar Finland Dr. P. Lund Analysis Tools Energy Systems France Mr. Y. Boileau Italy Dr. P. Zampetti Mr. Michael Holtz Oltmannsstrasse 5 Japan Mr. M. Yonekura Architectural Energy Corp. D-79100 Freiburg, Germany 2540 Frontier Ave. Mexico Dr. I. Pilatowsky Fax: 49/761-4588-132 Netherlands Mr. L. Bosselaar Boulder, CO 80301 USA E-mail:[email protected] Fax: 1/303-444-4304 New Zealand Mr. M. Donn E-mail: [email protected] Mr. F. Salvesen Task 26: Solar Combisystems Portugal Mr. J. Farinha Mendes Mr. Werner Weiss Spain Mrs. Delgado-Medina Task 23: Optimization of Solar Energy Use AEE Sweden Mr. M. Rantil in Large Buildings Gartengasse 5 Switzerland Mr. U. Wolfer Prof. Anne Grete Hestnes A 8200 Gleisdorf, Austria United Kingdom Dr. E. Perera Faculty of Architecture Fax: 43/3112-5886-18 United States Mr. D. Crawley Norwegian University of E-mail:[email protected] Science and Technology Chairman N-7491 Trondheim, Norway Task 27: Performance of Solar Facade Mr. Lex Bosselaar Fax: 47/73-59-50-45 Components NOVEM b.v. E-mail: annegrete.hestnes@ark. Mr. Michael K¬ohl P.O. Box 8242 ntnu. no Fraunhofer Institute for Solar 3503 RE Utrecht, The Netherlands Energy Systems Tel: 31/30-239-34-95 Task 24: Active Solar Procurement Oltmannsstr. 5 Fax: 31/30-231-64-91 Dr. Hans Westling D-79 100 Freiburg, Germany E-mail: L. [email protected] Promandat AB Phone: +49/761 4016682 Box 224205 Fax: +49/761 4016681 Executive Secretary S-104 51 Stockholm, Sweden E-mail:[email protected] Ms. Pamela Murphy Phone: 46/8-667-80-20 Morse Associates, Inc. Fax: 46/8-660-54-82 Task 28: Solar Sustainable Housing 1808 Corcoran St., NW Washington, DC 20009 USA E-mail:[email protected] Mr. Robert Hastings Tel: 1/202-483-2393 Architecture, Energy & Fax: 1/202-265-2248 Environment GmbH E-mail: [email protected] Kirchstrasse 1 CH-8304 Wallisellen, Switzerland Phone: +41/1/883-1717 or 16 S LAR UPDATE Fax: +41/1/883-1713 E-mail:[email protected] The Newsletter of the IEA Solar Heating and Cooling Programme Task 29: Solar Crop Drying No. 35, December 2000 Mr. Doug Lorriman Namirrol Ltd. Prepared for the IEA Solar Heating and 38 Morden Neilson Way Cooling Executive Committee Georgetown, Ontario The SHC Web Site by Canada L7G 5Y8 Visit the SHC web site next time Morse Associates, Inc. Phone: +1/905/873 3149 you’re on the Internet. You will find 1808 Corcoran St., NW Fax: +1/905/873 2735 Programme information, details on Washington, DC 20009 USA E-mail:[email protected] Task activities, publications, names Editor: of Programme contacts, calendar of Pamela Murphy upcoming SHC meetings and work- This newsletter is intended to provide informa- shops as well as other useful infor- tion to its readers on the activities of the IEA mation. Solar Heating and Cooling Programme. Its con- tents do not necessarily reflect the viewpoints or policies of the International Energy Agency, the Our Internet address is: IEA Solar Heating and Cooling Programme Member Countries, or the participating http://www.iea-shc.org researchers. 8