Status of Solar Heating/Cooling and Solar Buildings - 2023

Status of the Market for Solar Thermal Systems

Market Size and Trends

The Swiss market for solar thermal collectors further decreased by 10% in 2022 onto about 28,000 m2 which is only a sixth of the peak year 2009. Meanwhile, the Swiss PV market accelerates its increase to +60% (after+43% and +48% in the two previous years). More detailed market figures for solar thermal and PV are usually published in July each year and can be found here: www.swissolar.ch/de/angebot/news-und-medien/fakten-und-zahlen/statistik-sonnenenergie.
 
Solar thermal systems are still seen to be relatively expensive in terms of system costs. Evacuated collectors keep a small market share of about 11%. Unglazed collector installation increased by 20% with respect to 2021, due to fewer bigger projects (ice storage charging). Also, heat pump + PV solutions take over solar thermal market shares.
 
The installed total capacity of solar thermal collectors in Switzerland remains in 2022 at 1.71 Million m2, corresponding to a nominal power of 1.2 GW. 
The installed total capacity of PV in Switzerland exceeds 4.7 GWp (+30% compared to 2021).
 

Typical Applications and Products

About half of the collector market is forced circulation DHW (Domestic Hot Water) systems with ususally 50 litre storage volume per m2 collector area and a collector area of 4 to 6 m2. In terms of systems installed, the DHW systems for SFH (Single Family Housing) represent 55%, plus 21% DHW systems for MFH (Multi-Family Housing), totalling in 86% market share for DHW systems in general. From the remaining number of systems, the majority are combisystems and only few are solar thermal systems for other applications such as process heat. Amongst the combisystems (23% of all solar thermal systems), about 80% are for SFH and 20% for MFH. Summarizing, installations in single family homes are still dominating the market, with a slight trend to small collector areas (shift of shares from combisystems to DHW only).

Main Market Drivers

Besides external factors (CO2 tax with a very limited impact and fluctuating oil price), the Swiss solar thermal market is predominantly driven by the good will of private persons and the trust they put into this solution to help the planet and their wallet. This is why the market is primarily on single family houses and to a smaller extent also on pre-heating of DHW in dwellings. In addition, the Swiss cantons are about to establish cantonal building regulations requiring the use of renewable energy in new buildings or in the case of renovating the heating system. However, with the latest changes a stronger trend to heat pump solutions and PV can be observed.

Increased cantonal subsidies for domestic solar thermal systems can not make up for the tendency to further electrify the energy system. Missing subsidies and other incentives for solar district or solar industrial heating make it difficult to establish new and more profitable market branches.

Industry

The Swiss solar thermal industry is relatively small. About half of the collectors installed in Switzerland are imported, mainly from European countries. The other half originates from domestic production. From the total Swiss collector production, about one quarter is exported. Most products are sold via manufacturers to installers. Since the merger of two of the three dominant manufacturer on the market, a single market leader has emerged.

Employment

The Swiss solar professional association Swissolar estimates that there are about 2,000 jobs from the solar thermal market slowly shifting towards the solar PV market as well as towards the heat pump market or wood boilers suppliers.

Costs

As in the whole building sector, Swiss solar thermal systems are expensive compared to other countries. A DHW system covering about 60% of the needs by solar costs about 12,000 Euros for 6 m2 and 500 litre storage installed (without subsidies). These costs are mainly driven by installation costs (typically one third). A solar thermal system for domestic hot water supply in MFH with about 12 m2 collector area and 1,000 litre storage volume would currently cost about 2,000 Euro per m2 collector area installed without subsidies, and about 1,600 Euro per m2 including subsidies. Reducing the total cost is a challenge that we worked on together with the solar manufacturers in the framework of SHC Task 54: Price Reduction of Solar Thermal Systems. Some country specific regulations contribute to high costs of installation, e.g. the obligation to use scaffolds or comparable safety barriers when working on a roof.

Other Key Topics

Swiss installations tend to be of high standard corresponding to the demand of the market and better quality comes often at a price. One example: The use of (more expensive) stainless steel storages for domestic hot water installations is common instead of enameled steel storages. Quality controls are to be deployed with low-cost monitoring devices coming from pilot projects that showed their benefits.

Status of the Market for Solar Buildings

Scope

The brand MINERGIE® is a sustainability standard for new and refurbished buildings. It is mutually supported by the Swiss Confederation, the Swiss Cantons along with trade and Industry and is registered in Switzerland and around the world. Comfort is at the heart of MINERGIE® – the comfort of the users living or working in the building. A wholesome level of comfort is made possible by high-grade building envelopes and the continuous renewal of air. Specific energy consumption is used as the main indicator to quantify the required building quality. In this way, a reliable assessment can be assured. Only the final energy consumed is relevant.  

The MINERGIE® Standard is widely accepted. There are many reasons for this, the most important being the objective oriented approach: If builders and planners – in other words architects and engineers - can achieve the standard, they have complete freedom both in their design and choice of materials and also in their choice of internal and external building structures.

In the meantime, the building sector has developed a wide range of products and services for MINERGIE® buildings. Suppliers include architects and engineers as well as manufacturers of materials, components and systems. The diversity and competition of this market increases quality and lowers costs. The last product is a zero-energy building standard, called MINERGIE-A. MINERGIE-ECO that includes to address indoor environment quality is having a small market share in the MINERGIE market.

Since MINERGIE is a label for a project, quality controls of built MINERGIE projects must be undertaken. For this reason, MINERGIE started a supplementary product for quality assurance. This reaches out beyond the planning phase, to the construction and the operation phase of a building.

Market Size and Trends

Very typical heating technologies are heat pumps, especially for new buildings, sometimes in combination with PV. New legislation supports this trend, and it goes along with the MINERGIE® standard. Solar thermal combi systems never had a big market share which tends to continue to decrease.

Seasonal storage in water tanks is a proven solution in several pilot projects and a few houses or buildings choose it.

An emerging combination that has been demonstrated in several pilot and demonstration projects is heat pump and ice storage recharged by solar absorbers. Examples are a 75 m3 ice storage in a MFH in Rapperswil close to Zurich and the project « La Cigale » in Geneva which provides monitoring data in the internet that reveal promising results. As of today, there are several new projects in the planning and implementation phase.

Main Market Drivers

Cantonal support schemes for MINERGIE buildings or the national programme for building renovations (see www.dasgebaeudeprogramm.ch) are key drivers for the interest in energy efficient buildings. CO2 taxes remained at 120 CHF/t since national objectives were not met. But this has little effect on consumer choices since oil prices have decreased in greater proportions.

Legislation makes solar DHW mandatory in some cantons. Some subsidy schemes on low level exist in some cantons for solar collectors (per m2).

Employment

See statistics on www.swissolar.ch/ueber-solarenergie/fakten-und-zahlen/ (available in German, French and Italian).

Costs

From a solar heating and cooling point of view, a « typical » solar building in Switzerland would be a building equipped with a solar thermal system that provides DHW. Thus, such a « typical » solar building does not have significant additional costs. As a Swiss contribution to SHC Task 52: Solar Heat and Energy Economics, a tool was developed to give an indication of the benefits and costs of including solar thermal in energy supply concepts of living space (SFH, MFH, areal or heating net level), based on studies and literature available from several countries and installations. According to a recent study, the preheating of DHW by solar thermal for MFH leads to heat costs (whole system) of about 0.19 CHF per kWh in a typical case which is in the range (even slightly lower) that e.g. the total heat costs of a heat pump plus PV combination proposed as a standard setup in the MuKEn 2014 (regulations related to energy in buildings developed and agreed by the Swiss cantons).

Other Key Topics

The integration of both solar thermal and PV on the same roof with the same frame and shape is a topic under development as well as approaches to use the facade. PVT collectors and coloured collectors have been further developed in the past years. Coloured thermal collectors are expected to be on the market like the coloured PV modules that have been demonstrated on some buildings in Switzerland and Denmark, using the technology developed in Switzerland since 2001. One of the current core areas of research is the cost reduction, e.g. by drain back concepts with temperature limitation.

R&D Activities

R&D Programmes

In close cooperation with the most important funding agencies that competitively award grants, the Swiss Federal Office of Energy (SFOE) supports and coordinates research and innovation in the energy sector along a major part of the innovation chain. Swiss national R&D programmes exist for solar heat and heat storage, for solar industrial heat, and for energy in buildings. The activities of SFOE are based on a programmatic and subsidiary approach that is governed by the Federal Energy Research Masterplan.

The research programs are accessible to any organisation in Switzerland presenting a project that will be evaluated by the Swiss federal office of energy. Beside R&D projects, also pilot or demonstration projects can be applied for.

R&D Infrastructure

Institution Type Research Areas Involvement Website
HSR-SPF Research Institute at Univeristy of Applied Sciences Rapperswil Collector testing, heat storage, systems Task 14, 26, 32, 44, 49, 54, 58, 60 www.spf.ch
LESBAT HEIG-VD Solar energy for building research center Combisystems, solar and heat pump systems, LCA Task 26,44, 56 www.lesbat.ch
LESO-PB EPFL Building physics research center Collector thin layers with optical properties, integration in buildings Task 41 leso.epfl.ch
EMPA Building materials research center Dense heat storage Task 32,44 www.empa.ch
SUPSI Heat storage for buildings research center Simulation of ground storage www.supsi.ch
Vela Solaris AG Polysun Simulation software engineering company Simulation of solar and heat pump systems Task 26, 44 www.velasolaris.com
Meteotest AG Meteo forecast company Meteonorm data base Task 26, 36, 46 meteonorm.com
CUEPE UNIGE University energy in buildings research center Monitoring of systems, passive buildings simulation, heat storage Task 41, 46 www.unige.ch/energie
Sorane sa Private engineering company Simulation of complex systems Task 52 www.sorane.ch
CREM Municipal research center Energy management Task 52 www.crem.ch
HSLU CC-TES Research Group at University of Applied Sciences Lucerne Thermal Energy Storage Task 58 www.hslu.ch/en/lucerne-school-of-engineering-architecture/research/kompetenzzentren/thermal-energy-storage/
ZHAW-IUNR Research Institute at University of Applied Sciences PV-T lab and simulation, innovative system concepts Task 60 www.zhaw.ch/de/lsfm/institute-zentren/iunr/

Actual Innovations

The following innovations have been introduced in Switzerland:

  • Compact slurry ice generation through super-cooling processes achieve crystallizing powers of more than 10 kW (alternative to borehole sources; efficient recharging through solar thermal collectors)
  • Series production of self-learning, low-cost device to detect malfunction in solar thermal systems
  • Passive, thermo-hydraulic mechanism for covered PVT modules to prevent overheating
  • Temperature tailored PCM capsules to increase thermal capacities for partly-seasonal storages
  • Several extended and new software for system setup decision and dimensioning, district grid planning and tank stratification modelling

Support Framework

Background

The legal basis for the support of R&D and market dissemination measures for energy efficiency and renewable energy is the national law of energy. The CO2 reduction goals of Switzerland have been published (50% reduction in 2030 from 1990 levels). A May 2017 referendum called for more renewable energy and energy efficiency in Switzerland, and another June 2023 referendum mandates a net-zero CO2 target by 2050.

Government Agencies Responsible for Solar Thermal, for Solar Building Activities

In Switzerland, the government is responsible for the funding of R&D, whereas the cantons are responsible for building regulations and subsidies for renewable energy installations. Not all cantons are equal in their solar support.

Most Important Public Support Measure(s) for Solar Thermal and for Solar Buildings

The most important support measures for solar thermal are:

  • Financial support schemes for solar thermal installations provided by the cantons (say 300 to 600 euros per m2 as a general rule)
  • In 10 out of 26 few cantons have established building regulations where renewables are compulsory
  • Website qm-solar.ch to check the dimensioning of thermal solar systems as a precondition for public subsidies
  • Awareness raising provided by the national programme SwissEnergy as well as by the solar energy professionals association Swissolar
  • RD&D funding provided by the Swiss government
  • Quality control for solar thermal components and systems is provided by the SPF institute of the Eastern Switzerland University of Applied Sciences
  • energo (efficiency in existing heating installations) can monitor any installations linked to a heating room
  • A pilot project to detect solar installations failure or misactivity is about to deliver a low cost monitorong for tracking solutions together with a web site where every actor can follow a solar installation part of the monitoring programme (willing basis).

Information Resources

National Solar Associations (industry and non-industry)

National Associations on Green/Solar/Sustainable Buildings