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THE SOLAR THERMAL MARKET IN THE
1. The present market situation and future prospects
After the initial projects of the 70's and a modest 'boom', driven by government programs, in the first
half of the eighties, the market for active solar slumped in the period 1985-1989. Since then, a
gradually evolving introduction strategy has revived the market, which is now at its highest level yet.
By the end of 1994, approx. 50.000 m² of flat plate, glazed collectors (mostly for Domestic Hot Water)
and 80.000 m² of unglazed collectors (for swimming pools) had been installed. The 1994 figures were
10.300 m² glazed, 4.300 m² unglazed. In the growing market new manufacturers and importers see
opportunities: while a few years ago there were two, now there are six. However, the urge for low
prices while maintaining high performance and durability standards limits the number of suppliers.
At present the market for solar DHW systems is developed under a Long-term agreement between the
solar thermal industry and the Ministry of Economic Affairs . For solar thermal energy, the Ministry
has formulated a goal of 5 PJ (1,4 TWh) reduction of fossil fuel consumption by 2010, 40% of which
(2 PJ, 0,6 TWh) is to be realized by 300.000 solar DHW systems (900.000 m²). It was recognized that
this can only be achieved by a mix of measures, aiming at the development of a stable market. In
February 1994, an agreement was signed between the solar thermal industry, the Ministry of Economic
Affairs, 5 major energy distribution utilities, Holland Solar (the Dutch solar energy industry
association), and Novem (the Netherlands Agency for Energy and the Environment). Its objectives are
a 40% reduction in the installed system price from 1991 to 1997 and a market growth to 14.000
systems (approx. 40.000 m²) in 1997. This is to be achieved by a government-supported R&D
programme, cooperation with utility companies (including sales guarantees), public awareness
campaigns, and a government subsidy until 1997.
From 1995 the governmental subsidy is based on system performance. All systems have to be tested
under the Dynamical System Test-method. Subsidy for systems with glazed collectors is 486
ECU/MWh up to an annual output of 4,0 GJ (1.111 kWh), 216 ECU/MWh above it. The budget in
1995 is 3,9 million ECU. Some local governments and energy distribution companies provide an
additional subsidy. A number of energy distribution companies operate leasing schemes for solar
So far, the long-term agreement is approximately on schedule. The price reduction is on target,
although the increase in sales is a bit slower than projected. A significant part of the price reduction so
far has been achieved by the development of projects, in which larger numbers (often hundreds) of
systems are realized as a standard facility, thus reducing selling and installation costs in particular. At
the moment, over 80% of the systems are installed in such projects.
The prospects for the future are good: solar DHW is finding its place in the market. The public is
increasingly aware of the possibilities. Project developers, housing corporations, and municipalities
are asking for solar DHW in their housing developments. An increasing number of builders,
installers, and architects are familiar with the technology. Energy distribution companies stimulate
the application. With support from stricter building regulations concerning energy demand of new
buildings, it is believed that the target for the year 2010 can be met. This involves an annual market
for 15.000 systems (45.000 m²) in 2000 and 25.000 systems (75.000 m²) in 2010. Additionally, the
market for other applications will be developed. Preliminary discussions indicate a possible target
for 2010 of an additional 1-3 PJ (0,3-0,8 TWh) of fossil fuel reduction.
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2. Solar collector production and sales in the Netherlands
FLAT PLATE & VACUUM COLLECTORS UNGLAZED
Production and sales (m2) COLLECTORS
A B C D National Home
Total Exports Imports Total home production market
National m2 m2 market sales
1980 400 0 0 400 0 2.125
1981 415 0 0 415 0 2.485
1982 1.025 0 0 1.025 0 2.750
1983 1.935 0 0 1.935 0 3.800
1984 1.040 0 0 1.040 0 2.085
1985 5.300 0 0 5.300 0 7.850
1986 925 0 0 925 0 10.100
1987 2.340 0 0 2.340 0 5.300
1988 800 0 0 800 0 2.560
1989 1.215 0 0 1.215 0 4.210
1990 1.840 0 0 1.840 0 6.925
1991 6.000 0 0 6.000 0 8.865
1992 8.000 0 0 8.000 0 10.200
1993 7.150 N.A. 350 7.500 0 5.800
1994 8.300 N.A. 2.000 10.300 0 4.300
Total 46.685 N.A. 2.350 49.035 0 79.355
Table 2.1. Solar collector production and sales
Notes concerning the statistics: Main sources for the statistics are data provided by Holland Solar
for the period up to 1987 and data from the agency carrying out the government subsidy scheme for
the period afterwards . Manufacturers indicate that the figures show a time lag compared to the
actual situation. This is probably caused by the fact that some buyers (e.g. utility companies) only
claim the subsidy some time after realization of the systems.
The import fraction is a rough estimate, based on knowledge of realized projects. In the past few
years, some export has been realized. Due to the limited number of manufacturers involved, it is not
possible to obtain exact figures.
2.1 Estimated park of solar collectors in working order:
based on : 0,6 x (total 1987) + 0,95 x (total 1988-1994)
Glazed collectors = 42.000 m²
Unglazed collectors = 63.000 m²
Total = 105.000 m²
2.2 Estimated annual solar thermal energy production:
Glazed collectors = 41.900 m² x 375 kWh/m².year = 15.700 MWh/year
Unglazed collectors = 62.600 m² x 250 kWh/m².year = 15.650 MWh/year
Total = 31.360 MWh/year
2.3 Avoided CO2 emissions:
Glazed collectors = 15.700 MWh x 0,17 tonnes/MWh = 2.700 tonnes/year
Unglazed collectors = 15.650 MWh x 0,17 tonnes/MWh = 2.700 tonnes/year
Total = 5.400 tonnes/year
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3. Product types and solar thermal applications
Unlike in other EC-countries, in The Netherlands the drainback system is customary. An estimated
95% of the SDHW systems is a forced circulation drainback system. This is due to the fact that water
companies prefer water as a collector fluid to antifreeze. As in most northern countries there are
relatively few thermosiphon systems, with antifreeze as the collector fluid.
Because of national resources, natural gas is used in most houses for auxiliary heating.
Most thermosiphon systems are Solaharts imported from Australia. The system is slightly adapted to
the Netherlands situation. The water tank is not on the roof, but above the collector in the attic of
Newcomers are two different ICS-systems developed in the Netherlands, entering the market in
1995 under the trade names of Solution and Solistor.
Collectors for swimming pools are mainly made of EPDM. Some larger public swimming pools
have glazed collectors.
4. Product technology and production methods
Use of materials for drainback and thermosiphon systems:
Absorber: copper with spectrally selective layer of black chromium, or copper tubes with
aluminium fins with spectrally selective layer of nickel-pigmented anodised aluminium, or copper
Glazing is tempered low-iron glass or polycarbonate.
Insulation of collector is with foam glass, glass wool or polyurethane (CFC-free).
Storage tanks: stainless steel or copper
Tank insulation: polyether, polystyrene, polyurethane or black polyester.
The drainback systems are controlled by temperature difference. Thermosiphon systems have a relief
valve for pressure security. Pressure security of the storage, containing water from the mains, is in both
cases a safety valve. Temperature is secured by collector shut-off for the drainback and by draining hot
water for the thermosiphon. The Integral Collector Storage (ICS) systems have a tank made of
stainless steel or copper; they have a safety valve and drain hot water as temperature security.
Heat exchangers have a single separation: drainback systems have an internal helix or double wall,
thermosiphon only double wall. The ICS's are direct systems, containing drinking water.
In systems with a typical sizing for the Netherlands market, both drainback and thermosiphon
systems have an average annual thermal system output of approx. 1.100 kWh (4,0 GJ). For
drainback systems the corresponding collector area is 2,8 m² (output approx. 400 kWh/m², rated at
375 kWh/m² after correction for pump electricity); for thermosiphon systems it is 3,7 m² (output
approx. 300 kWh/m², no pump electricity). The newly developed Integratal Collector Storage
systems are sized slightly smaller, with an annual thermal system output of approx. 940 - 1.000
kWh (3,4 - 3,6 GJ). At an effective area of 2,2 - 2,8 m² this is equivalent to approx. 330 - 450
kWh/m² (no pump electricity).
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This output is based on the performance ratings for the subsidy scheme, assuming a daily hot water
demand of 110 litre at 65 °C (the relatively high demand temperature limits the system output). It is
valid for the average annual irradiation on a South-facing plane with a slope of 45° in the centre of
the country: 1.110 kWh/m² (corresponding to 980 kWh/m² on the horizontal plane).
5. Breakdown of solar system costs
In table 5.1 an estimation is given of the system costs of a typically sized SDHW-system. For the
individual buyer a system is much more expensive than in projects, mainly because of higher
distribution, selling and installation costs.
Total costs (excl. VAT) 1.500 - 2.500 ECU 1.100 - 1.200 ECU
VAT (17.5%) 263 - 438 ECU 190 - 210 ECU
Total costs (incl VAT) 1.760 - 2.940 ECU 1.290 - 1.410 ECU
Table 5.1. Breakdown of solar system costs for typically sized systems.
A further division of costs is not feasible due to the variation in system types and confidentiality of
6. Research and development aimed at improving products
The Ministry of Economic Affairs has funded National R&D Programmes on Solar Thermal Energy
since 1978. At present, Novem is assigned the management of this programme. In the Long-Range
Plan 1990 - 1994, research and development has concentrated on SDHW-systems. Under the Long-
term Agreement discussed before, the primary R&D goal is to contribute to the 40% price reduction
for solar DHW deemed necessary to achieve a stable market after the phase-out of government subsidy
after 1997. In recent years, the annual Novem budget for active solar R&D has been on the order of 2
R&D activities are mainly carried out by manufacturers (co-funded from the National Programme),
by TNO Building and Construction Research and by several consultancies.
7. Product distribution networks, marketing and after sales methods
There is a shift from direct distribution of solar water heaters from the
*************************************************************SDHW as standard
facility, one installing company). The first and, to date, largest example is the Apeldoorn Solar
Project, realized with EC Thermie-support. In this project, that is now halfway its realization phase,
1.000 systems are being installed in a new housing development of 1.700 houses in total. At the
moment, already 80% of all systems are sold in projects.
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Besides the normal marketing activities of manufacturers and installers, a national campaign was
launched by Novem and Holland Solar to improve the awareness of the public for solar thermal
energy. In the campaign the environmental aspects and the potential of sun in such a northern
country were stressed. The campaign is aimed at consumers that are technically interested and/or
environmentally conscious. Holland Solar handles the response to Novem-commercials in
newspapers and on radio. As a result of the campaign 66% of the population now knows what an
SDHW system is.
EnergieNed, the Association of energy distribution companies, regularly formulates its
environmental goals in an Environmental Action Plan. Based on this central plan, the individual
energy distribution companies draw up their own Environmental Action Plans. Some of the
companies have included solar water heaters in their plans. This involves promotion, incentives,
leasing, and technical support.
VNI, an organisation of installers, offers special courses on solar water heaters for its members and
they have a special businessgroup for approved SDHW-installers. A checklist for correct installation
Energy distribution companies and other customers of large numbers of systems often inspect the
systems on completion, using a standard inspection format, to ensure that installation errors are
corrected before the system comes into use.
8. Incentives and financing methods
Since 1995 the subsidy is based on the performance of the system. All systems have to be tested under
the DST-testmethod. Subsidy for systems with glazed collectors is 486 ECU/MWh (275 NLG/GJ) up
to 4,0 GJ, 216 ECU/MWh (125 NLG/GJ) above it. The subsidy for systems with unglazed collectors is
61 ECU/MWh (35 NLG/GJ).
The governmental budget in 1995 is 3.9 million ECU. As arranged in the Long-term Agreement the
government subsidy will be ended after 1997. Some local governments provide an additional subsidy.
A number of energy distribution companies operate leasing and renting schemes for solar DHW
systems, sometimes also providing subsidies.
9. Typical solar domestic hot water system
The drain back system is the most common in the Netherlands. Main manufacturers are Luigjes
Zonne-Energie (LZE) and Zonne-Energie Nederland (ZEN). The ZEN systems are marketed by Agpo
(heating systems). New on the market are low-flow systems manufactured by ATON.
Size: the average collector area is 2,8 m2;
Type: drainback with heat exchanger;
Energy production: 2,8 m2 x 375 kWh/m2 = 1.050 kWh.year (after correction for pump electricity).
10. Standards and codes of practice 
For solar heaters several specific regulations have been developed recently or will be finished in the
coming years. It is part of the governmental stimulation programme to be certain of only well-
functioning systems on the market. For solar DHW systems, TNO Building and Construction
Research in Delft carries out performance testing and a provisional quality check (title: Dynamic
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Testing of Solar Domestic Hot Water Systems, ). CIWI, an agency founded by two research
institutes for the certification of wind turbines, was recently assigned for the quality certification of
SDHW systems as well (title: Quality declaration for Solar Domestic Hot Water Systems). The
certificates will be based on tests done by TNO, concerning documentation, durability, and safety and
on the results of a DST performance test. In April 1995, the first quality certificate has been issued.
The Netherlands Normalisation Institute (NNI) has set up a general standard for drinking-water. The
organisation of water companies, VEWIN, is responsible for the technical details and has made
worksheets for use by the water companies as practical standards. These worksheets refer to the
EUREAU document. Recently, VEWIN has developed a specific worksheet for solar DHW systems,
Worksheet 4.4.C. According to this worksheet only fluids with a KIWA ATA-certificate are allowed
in heat exchangers with single separation or as intermediate in heat exchangers with double separation.
Otherwise heat exchangers must have a double separation. The heat exchangers have to fulfil the
requirements as stated in the VEWIN guideline BRL-K656 (Heat exchangers must withstand a
maximum pressure of 1000 kPa and they must be resistant to 90°C at least).
Certification of water appliances and heat exchangers is done by KIWA, of natural gas appliances by
GASTEC and of electric appliances by KEMA. At present, a new Foundation (Stichting Gaskeur),
with representatives from Gastec and the industry, is preparing new certificates for gas-fired
appliances. Possibly it will also include a certificate for the application of gas-fired appliances as
auxiliary heaters for SDHW systems.
11. Conventional water heating systems and energy prices
Because of large national resources gas-fired water heaters are most commonly used, in 86% of the
households . Combined, condensing boilers for space heating and Domestic Hot Water are the
standard facility in new housing, and are often applied in retrofit as well. At the moment their
penetration in the total stock is 42%. Some electric boilers are still in use, but their share is
decreasing: at the moment, 9% of the households has an electric boiler as its main DHW system.
The Netherlands have extensive R&D on energy-efficient natural gas-applications. This has led to
innovative solutions for the combination of a solar DHW system and its gas-fired backup heating.
Recent developments concern system integration of solar water heaters with the conventional water
heater. For the Aquasol (manufactured by ZEN) the vessel is integrated with a standard heating
boiler as auxiliary heater. The “ZonneGasCombi” (LZE), the solar-gas combination, uses one vessel
for storage, space heating and DHW.
Energy prices in The Netherlands are among the lowest in the European Union. The prices vary
regionally. The ranges stated below are valid for the first half of 1995; excl. VAT (17.5%). 1 ECU =
2,06 NLG, 1m3 of natural gas = 31,65 MJ (LHV) = 8,79 kWh (LHV).
Date: 1995 Households Large consumers
(excl. Vat 17,5%) (excl. Vat 17,5%)
Electricity - normal (single tariff) 78-112 ECU/MWh
Electricity - nighttime (reduced tariff) 42-49 ECU/MWh
Natural gas 21,6-25,1 ECU/MWh above 170.000 m3 annually:
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Table 11.1. Conventional energy prices
Starting on 1 January 1996, The Netherlands will introduce a 'regulating energy tax', aiming at
increased energy efficiency. The tax will be levied from small consumers (mainly households); the
revenue will be used to lower general taxes (income tax, corporation tax). After 3 years the tax will
amount to approx. 20% of energy prices including VAT: 0.11 NLG/m³ (0.054 ECU/m³) for natural
gas, and 0.035 NLG/kWh (0.017 ECU/kWh) for electricity.
12. National energy policy
In 1990, the government submitted the revised National Environmental Policy Plan, 'NMP Plus'. In
this plan a reduction of CO2-emission of 3-5% is aimed at for the period 1990-2000, instead of an
increase under 'business-as-usual' of 16%.
The Energy Department in the Ministry of Economic Affairs formulates the governmental policy for
energy R&D, demonstration and market introduction. An ambitious energy conservation policy was
outlined in its "Memorandum on Energy Conservation" published in 1990. The target for solar thermal
energy was set at a 5 PJ (1,4 TWh) reduction in fossil fuel consumption in the year 2010 (0,2% of
Novem, the Netherlands Agency for Energy and the Environment, is the primary agency for
implementing the R&D policy. Within the framework of the Memorandum, Novem runs a programme
to stimulate the application of solar DHW systems. The aim is to go from about 6.000 installed SDHW
systems in 1992 to 300.000 systems in 2010. This would account for 2 PJ (0,6 TWh), or 40% of the
national target. At the moment, there are plans to fill in the remaining 3 PJ (0,8 TWh) with non-
SDHW applications and passive solar.
In 1995, a new national building code will be introduced, in which a limit is set on the total amount
of energy used by new buildings, including DHW consumption. Solar energy is accounted for in the
calculations. If the limit is set tight (aiming at a low energy use), SDHW systems could become one
of the most cost-effective options.
EnergieNed, the Association of energy distribution companies, regularly formulates its
environmental goals in an Environmental Action Plan. In the 1994 edition, the goal for solar energy
(mainly active solar) was 0,9 PJ (0,3 TWh) in the year 2000. At present, the possibilities are studied
to set ambitious targets for the year 2010 in the 1996 Environmental Action Plan.
Despite the efforts so far, the national CO2-emissions have increased by 10% since 1990, mostly
due to the economic recovery. Recently, the Minister for the Environment concluded that additional
measures will be necessary to meet the target.
13. Objectives for the solar industry
The objectives for solar DHW systems are broadly supported: the Long-term Agreement, mentioned
above, is based on the government's target of 300.000 solar DHW systems by the year 2010. At the
moment, 10.000 systems are in place. The market growth is slower than projected in the Agreement,
which aimed at a market of 14.000 systems annually in 1997, leading to 46.000 systems installed by
the end of 1997. Novem now puts the target at 50.000 systems by the year 2000. A possible scenario
is outlined in the following table.
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Year Sales (systems) Cumulative Collector Area (m²) Cumulative (m²)
- 1993 7.500 22.500
1994 2.500 10.000 7.500 30.000
1995 5.000 15.000 15.000 45.000
1996 7.000 22.000 21.000 66.000
1997 8.000 30.000 24.000 90.000
1998 10.000 40.000 30.000 120.000
1999 12.000 52.000 36.000 156.000
2000 15.000 67.000 45.000 201.000
2005 25.000 180.000 75.000 540.000
2010 25.000 300.000 75.000 900.000
As stated before these SDHW targets account for 40% (2 PJ (0,6 TWh)) of the overall target for
solar thermal energy. The plans for realizing the remainder are being elaborated at the moment. It
has been proposed to aim at 1-3 PJ (0,3-0,8 TWh) of fossil fuel reduction by other active solar
applications, such as:
large hot water systems for services, as hospitals and homes for the elderly
niche markets for unglazed collectors (solar drying, swimming pool heating).
This would increase the collector areas mentioned in the table above by roughly 50 - 150%.
For the year 2000, Novem foresees the realization of large solar thermal systems on 700 buildings
(up from 300 in 1994) and 2.000 swimming pools (up from 1.800 in 1994).
Central solar heating plants with seasonal storage are a future option with a large technical potential.
The Groningen system (2.400 m² vacuum tubes; 23.000 m³ ground storage) however, built in 1984,
has not yet had a follow-up. Since this type of system can only be realized on a large scale, the
investment costs for a single project are high. In housing developments with a heat distribution
system, heat from cogeneration plants is a strong competitor for solar heat for the short and medium
term. Most new central electricity generating plants are of a cogeneration/district heating type, and
there are possibilities with gas turbines on a smaller scale as well. Novem foresees one new project
with this technology in the period up to the year 2000.
Glazed Unglazed Total Total Solar Avoided
collector collector glazed unglazed thermal CO2
sales sales collector collector energy emissions
sales sales production
m2 m2 m2 m2 GWh/year tonnes/year
112.000 5.000 830.000 120.000 340 58.000
Table 13.1. Prospect solar market and environmental impact in the year 2005.
14. Strategy to attain the targets
The strategy to realize the solar DHW targets is to create a stable market of approx. 15.000 systems
(45.000 m²) under the existing Long-term Agreement. This is to be achieved around 1997/1998. The
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cost level by then (approx. 1.000 ECU for an installed system) is supposed to sustain the market
without further subsidies. There are a number of ways to make sure that this will be the case:
A tight limit on energy consumption of new houses so that SDHW systems become one of the
most cost-effective options.
Continued support by the energy distribution companies.
Low-cost financing for SDHW projects from 'Green funds', that can pay out tax-free dividends to
their investors under a recent law to promote investment in the environment.
Support by local authorities, e.g. by the promotion of the application of SDHW in their new
On the basis of this stable market, the industry should be able to further develop the market on a
The strategy to realize the targets for other applications is still under discussion. If these targets are
adopted in the Novem Long-range plan, the actions can be co-funded from the National R&D
Programme. They can also fit in the Environmental Action Plans of regional utilities.
The elements will be:
Identification of the most interesting markets
System study to explore the optimal system type and dimensioning
Demonstration projects with organizations in the sector
Knowledge transfer to market parties / marketing by the industry.
15. Results expected when the targets are reached
A stable market for solar thermal energy, based on SDHW systems, from 1998 onwards.
A strong industry, able to invest in automated production equipment, in extensive marketing and
in applied R&D.
An infrastructure (installers, builders, training, etc.) that can handle solar thermal energy systems
as a standard facility.
Reduction of fossil fuel consumption and associated CO2-emissions:
2000 0,14 - 0,3 TWh (0,5 PJ - 1,0 PJ) 28.000 - 56.000 tonnes CO2
2010 0,8 - 1,4 TWh ( 3 PJ - 5 PJ) 168.000 - 280.000 tonnes CO2
 The Dutch Programme for the Development of Solar Thermal Energy.
T.P. Bokhoven, ZEN BV, October 1994
 Dynamic Testing of Solar Domestic Hot Water Systems
Vol A: development and evaluation of the dynamic test procedure.
Vol B: Participant contributions
TNO Building and Construction Research, Delft, December 1992.
 Survey of thermal solar energy systems in the Netherlands, Period 1975-1993 (in Dutch),
Ecofys, Utrecht, September 1994.
 Quarterly surveys of thermal solar energy systems 1993 (in Dutch)
Ecofys, Utrecht, August 1994.
 Environmental aspects of the material use for Solar Water Heaters (in Dutch)
Ecofys, Utrecht, October 1994.
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 Solar Water Heaters in Drinking-Water Systems,
a Survey of Technical and Regulatory Aspects in the Countries of the European Community
Ecofys, Utrecht, December 1993.
 Basic research on the use of natural gas by small consumers (BAK '93) (in Dutch),
EnergieNed, Arnhem, May 1994.
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SOLAR THERMAL DIRECTORY Technical consultants specialised in
Manufacturers and distributors of solar
thermal equipment BROUWER ENERGIE CONSULT
Vijverlaan 11, NL-7316 DE APELDOORN
LZE (Luigjes Zonne-energie) Tel. +31 55 22 02 00 Fax. +31 55 21 13 48
Gildeweg 15, NL-3771 NB BARNEVELD Contact: Mr. G. Brouwer
Tel. +31 34 20 131 35 Fax. +31 34 20 929 05 Number of employees: 2
Contact: Mr. T. Luigjes
Manufacturer of drainback systems DWA INSTALLATIE- EN ENERGIEADVIES
Number of employees: 16 P.O. Box 274, NL-2410 AG BODEGRAVEN
Member of Holland Solar Tel. +31 17 26 502 60 Fax. +31 17 26 514 99
Contact: Mr. L van Bruchem
ZEN (Zonne-energie Nederland) Number of employees: 30 (solar thermal: 4)
Hurksestraat 18G, NL-5652 AK EINDHOVEN
Tel. +31 40 55 06 76 Fax. +31 40 51 31 61 ECOFYS RESEARCH & CONSULTANCY
Contact: Mr. J. van Dam P.O. Box 8408, NL-3503 RK UTRECHT
Manufacturer of drainback systems Tel. +31 30 91 34 00 Fax. +31 30 91 34 01
Number of employees: 10 Contact: Mr. C.J. van der Leun
Member of Holland Solar Number of employees: 32 (solar thermal: 5)
Member of Holland Solar
Akkersrijt 4002, NL-5692 DA SON LEVEL ENERGY TECHNOLOGY
Tel. +31 49 90 606 02 Fax. +31 49 90 615 04 Panterlaan 20, NL-5691 GD SON
Contact: Mr. H.J. Bodewes Tel. +31 49 90 604 98 Fax. +31 49 90 604 67
Importer of Solahart solar water heaters Contact: Mr. Bart Veltkamp
Number of employees: 4 Number of employees: 5 (solar thermal: 2)
Member of Holland Solar
Principal sources of information
Postbus 2185, NL-5600 CD EINDHOVEN NOVEM, Netherlands Agency for Energy and the
Tel. + 31 40 81 86 03 Fax. +31 40 81 83 56 Environment
Contact: P. Kalkman P.O. Box 8242, NL-3503 RE UTRECHT
Manufacturer of ICS systems Tel. +31 30 36 34 44 Fax. +31 30 31 64 91
Number of employees: 8 Contact: Mr. L. Bosselaar, Mr. A.F.J. van de Water
Member of Holland Solar
HOLLAND SOLAR (Dutch solar energy industry association)
SOLUTION ENERGY SYSTEMS BV Korte Elizabethstraat 6, NL-3511 JG UTRECHT
Meijnerswijk 5, NL-6841 HA ARNHEM Tel. +31 30 32 80 08 Fax. +31 30 34 11 76
Tel. +31 85 21 35 75 Fax. +31 85 21 61 86 Contact: Ms. J.B. Haring
Contact: Mr. J. Thomassen
Manufacturer of ICS systems NNI (NETHERLANDS NORMALIZATION INSTITUTE)
Number of employees: 10 P.O. Box 5059, NL-2600 GB DELFT
Member of Holland Solar Tel. +31 15 69 01 90 Fax. +31 15 69 01 30
ATON GASTEC NV, Certification
Wilhelminastraat 13, NL-4194 TT METEREN P.O. Box 137, NL-7300 AC APELDOORN
Tel. +31 34 56 92 65 Fax. +31 34 56 94 02 Tel. +31 55 49 45 78 Fax. +31 55 41 89 63
Contact: Mr. J. Heidemans Contact: ing. W.J. Jordense
Manufacturer of low-flow drainback systems
Number of employees: 2 Testing Facilities and Solar Research
Sluisweg 30 A, NL-5145 PE WAALWIJK TNO BUILDING AND CONSTRUCTION RESEARCH
Tel. +31 4160 315 49 Fax. +31 4160-372 98 P.O. Box 29, NL-2600 AA DELFT
Contact: Mr. L.J. de Jongh Tel. +31 15 60 84 03 Fax. +31 15 60 84 32
Importer of swimming pool collectors Contact: Mr. B. van der Ree
Member of Holland Solar
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