Solar water heating · Pully

Solar Thermal in Pully: A Comprehensive Guide for Homeowners

Switching to solar thermal is a key step in improving your home's energy efficiency in Pully. This guide details the technical and administrative aspects specific to this Vaudois municipality.
Solar water heating – Pully

Worked examples in Pully

Small project

CHF 10'100 – CHF 23'600

Typical project

CHF 13'000 – CHF 30'200

Large project

CHF 17'800 – CHF 41'000

Computed with our estimator for Pully (regional factor included), standard finish. Only the project size changes.

Cost split (typical project)

  • Labour : CHF 8'400 (40 %)
  • Materials : CHF 10'500 (50 %)
  • Other costs : CHF 2'100 (10 %)

Why and when to consider solar thermal in Pully

Pully benefits from favorable sunshine, making solar thermal particularly relevant for meeting your domestic hot water needs. At an altitude of 426 meters and with a temperate climate, installing collectors significantly reduces reliance on fossil fuels for most of the year.

Solar thermal collectors generally cover a large portion of summer hot water needs, optimizing your annual energy consumption. The city's commitment, as a certified Energy City, actively encourages this transition.

The ideal time to undertake this work is often when replacing your boiler or during a comprehensive renovation of your heating system. It is strategically wise to plan this work before the significant frost periods, with an average of 44 frost days per year, to ensure optimal installation before winter.

Early planning allows for better integration of the system into the existing structure.

Technical choices for your solar project

The sizing and choice of collectors are crucial to the success of your installation. You must choose between flat plate collectors, often used for hot water, and evacuated tube collectors, which are more efficient in cold weather. The choice will depend on your specific hot water needs and available roof space.

Combining collectors with a heat pump requires a rigorous sizing study to ensure optimal efficiency year-round, especially during days of intense cold.

There are different quality levels depending on the materials and desired durability. Forced circulation systems, unlike thermosiphon systems, offer greater flexibility for roof installation.

It is essential to engage a qualified professional capable of analyzing the slope and orientation of your roof to maximize performance. A preliminary thermal study helps validate the best technical and economic compromise while ensuring the long-term viability of your investment.

Specificities of the local building stock and points of vigilance

Pully's building stock consists of structures from a wide variety of eras. If your house was built before 1990, special vigilance is required regarding the potential presence of asbestos in construction materials or insulation.

When installing collectors, it is necessary to check the condition of your roof, its watertightness, and its structural capacity to support the weight of the installation. Existing distribution networks must also be compatible with the new solar system to avoid unnecessary energy loss.

6 °C, makes it essential to properly insulate the pipes transporting the heat transfer fluid to prevent external thermal losses. For older houses, prior energy renovation of the building envelope can greatly improve the overall performance of the solar installation.

It is advisable to have a technical diagnosis carried out by a specialized firm that will identify any constraints related to your specific structure before any detailed planning.

Regulations, permits, and heritage in Pully

In the canton of Vaud, the procedure for installing solar collectors is generally facilitated. You fall under a simplified procedure or an exemption from the building permit for this equipment. However, if your building is located in a protected area or is heritage-listed, specific constraints may apply.

These areas may require special aesthetic integration, such as flat-mounted panels or a specific color, to respect the original exterior appearance.

Before starting, it is essential to contact the competent authorities, the municipality, or the prefect to confirm the status of your plot. If you are located in a historic perimeter, respecting the exterior appearance is a priority.

Although solar installations are encouraged, they must not distort the aesthetics of protected buildings. Prior consultation with the municipal urban planning department will save you any future administrative complications and ensure that your project complies with the local regulations in force.

Financial aid and taxation

The Buildings Program (VD) offers subsidies for solar thermal as a flat contribution or per square meter of collectors, providing valuable assistance to offset your investment. It is imperative to submit your application before starting the work, otherwise, you may lose your right to financial aid.

Be sure to consult the official website to know the specific eligibility criteria for your project.

Regarding taxation, investments aimed at saving energy are tax-deductible. The deduction rate is 100% of the costs borne by the owner. If the cost of the work exceeds your net taxable income, it is possible to carry over the balance to the next two tax periods.

Note, however, that you cannot combine this deduction with the flat-rate deduction for maintenance expenses. This is an important annual choice to make when filing your tax return, taking into account that subsidies already received must be deducted from the total costs.

Schedule and construction process

The execution of a solar project follows several key stages. It all begins with a feasibility study and the subsidy application. Once this is validated and permits are obtained, the technical planning phase can begin. The choice of craftsmen is crucial.

The construction period should be chosen to minimize inconvenience. Although no season is strictly prohibited, it is preferable to avoid periods of intense frost for exterior work on the roof, facilitating the work of installers and ensuring secure commissioning.

The construction site generally begins with roof preparation, followed by the installation of mounting systems and the collectors themselves. Next, the hydraulic connection to the storage tank and your existing heating system is carried out.

The pressure test, filling the circuit with heat transfer fluid, and commissioning complete the intervention. Good construction oversight ensures your installation meets standards, guaranteeing the performance and durability of your new renewable energy source.

Common mistakes and preparation checklist

Avoid classic mistakes by not starting your work before receiving confirmation of your subsidy. Another common mistake is neglecting the analysis of the roof structure's condition before placing heavy loads on the roof.

Ensure that the installer provides a sizing study that takes into account your actual needs and not an overestimated one. Also, check that the chosen components are of high quality to avoid premature maintenance costs.

Before requesting quotes, prepare your checklist : check the date of your last roof renovation, examine the insulation level of your house, gather your heating system plans, identify if your building is protected or in a heritage area, and list your annual heating bills.

By asking precise questions about the warranty of the collectors and the expected performance when requesting quotes, you ensure that you select the most reliable provider. This rigorous preparation is the key to the success and profitability of your installation.

Grants and subsidies

Canton

Solar thermal — Buildings Programme (VD)

Flat contribution or per m² of collectors.

Grants for solar thermal systems (hot water, heating support).

www.leprogrammebatiments.ch

Check amounts and conditions with the provider before signing: apply before work starts in most cases.

Companies in the area

Société Coopérative Atelier LTC

1005 Lausanne · about 3.8 km

Atelier LTC is a Lausanne-based cooperative specializing in heating systems, solar thermal installations, and sheet metal work.

atelierltc.ch

SaniCalor Pro Sàrl

1005 Lausanne · about 3.8 km

Specialist in heating systems, heat pumps, sanitary services, and solar thermal installations with 24/7 emergency service in Lausanne and Zurich regions.

sanicalor.ch

CONSTECH SA

1003 Lausanne · about 4 km

Lausanne-based engineering and general contractor specializing in energy-efficient renovations, HVAC, building envelopes, and solar systems.

constech.ch

RT Réseaux thermiques SA

1003 Lausanne · about 4 km

RT Réseaux thermiques SA specializes in energy services, renewable energy, and thermal network heating solutions.

rtsystem.ch

Suggestions from the commercial register by distance and activity. Not an endorsement or partnership.

Frequently asked questions

Can solar thermal replace my heating system?

Solar thermal is ideal for hot water but usually acts as a supplement. For full heating, a hybrid system with a heat pump is often required.

How many sunny days are needed in Pully?

The system works thanks to global radiation, not just in direct sunlight. Even with cloudy skies, the collectors capture the necessary energy to preheat water.

Do I need a permit to install panels?

In Pully, the procedure is simplified. However, if your building is protected, an authorization is still necessary to guarantee the exterior appearance.

Is installing collectors risky for my roof?

If the mountings are correctly installed by a qualified professional, there is no risk. The seal must be checked before any installation.

Is it profitable with 44 frost days per year?

Yes, because modern systems use antifreeze fluids. Annual performance remains high despite winter cold spells.

Can I combine subsidies and tax deductions?

You can deduct the actual costs remaining after subtracting subsidies. However, it is not possible to combine the energy deduction with the flat-rate deduction.

Do solar panels need maintenance?

A periodic check every few years is enough to verify the seals and the level of the heat transfer fluid. This ensures a long life for your system.

Useful local data

Estimated solar yield — 1'199 kWh/kWc/an (toit ~30° sud, PR 0.8, estimation)

Source : Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024) · estimate

Altitude — 426 m

Source : swisstopo – service d'altitude (MNT)

Heating degree days — 2'776 Kj/an (20/12 °C)

Source : Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024)

Frost days — 44 jours/an

Source : Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024)

Solar irradiation — 1'363 kWh/m²/an (horizontal)

Source : Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024)

Winter design temperature — -4.2 °C (1er percentile des minimales)

Source : Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024)

Mean temperature — 11.6 °C

Source : Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024)

Energy policy

  • Note : La Ville de Pully mène une politique énergétique pragmatique depuis 25 ans. Le label Cité de l'énergie a été obtenu le 25 septembre 2017. Le Concept énergétique de la Ville de Pully a été adopté en mars 2015. Depuis le 1er janvier 2019, la Municipalité encourage les économies d’énergie et le développement des énergies renouvelables auprès de la population grâce au programme Ecowatt.
  • Targets : Contribuer à un développement énergétique durable du territoire communal; contribuer à la mise en œuvre de la Stratégie énergétique 2050 de la Confédération; réduire de plus de 20% la consommation annuelle de l'éclairage public (objectif atteint); objectifs à l'avenir: mettre en place un outil de planification technique et financier pour l’assainissement énergétique des bâtiments administratifs, rénover le site du Prieuré en respectant le « Standard Bâtiments 2015 », acquérir de nouveaux véhicules électriques alimentés avec de l’électricité certifiée 100% renouvelable.
  • Label year : 2017
  • Climate plan : Concept énergétique de la Ville de Pully
  • Label : Cité de l'énergie

Source : Pully.ch - Energie

PermitsCanton

  • Competent authority : municipalité ou préfet
  • Solar panels : Soumis à la procédure simplifiée ou dispense de permis de construire
  • Heat pump : Soumis à la procédure simplifiée ou dispense de permis de construire. Pour les pompes à chaleur air-eau ou air-air, les nuisances sonores sont prises en compte.
  • Procedure : procédure simplifiée de permis de construire (dispense de permis de construire)
  • Windows and facades : Soumis à la procédure simplifiée ou dispense de permis de construire, sauf si le bâtiment est protégé ou situé dans une zone protégée, ou si les travaux entraînent un changement d'affectation, d'aspect extérieur ou de gabarit important.

Source : Canton de Fribourg: Permis de construire (example, this is Fribourg) · estimate

Tax deductionsCanton

  • Note : Le contribuable peut choisir, lors de chaque période fiscale et pour chaque immeuble, entre la déduction des frais effectifs et la déduction forfaitaire. La déduction forfaitaire couvre les frais d'entretien, de remise en état d'immeubles acquis récemment, d'administration par des tiers, d'investissements énergétiques, de démolition et de primes d'assurances.
  • Carry-forward : Si les coûts d'investissement destinés à économiser l'énergie et à ménager l'environnement ou les frais de démolition en vue d'une construction de remplacement ne peuvent pas être entièrement pris en considération fiscalement durant l'année où ils ont été engagés, le solde peut être reporté sur les deux périodes fiscales suivantes. Les dépenses peuvent être reportées si le revenu net est négatif. Si des frais sont reportés, il n'est pas possible de faire valoir une déduction forfaitaire pendant cette période fiscale. En cas de déménagement en Suisse ou de transfert de la propriété de l'immeuble, le contribuable conserve le droit de déduire le solde des frais pouvant être reportés.
  • Maintenance costs : Le contribuable qui possède des immeubles privés peut déduire les frais nécessaires à leur entretien, les primes d'assurances relatives à ces immeubles et les frais d'administration par des tiers.
  • Energy investments : Sont réputés investissements destinés à économiser l'énergie et à ménager l'environnement les frais encourus en vue de rationaliser la consommation d'énergie ou de recourir aux énergies renouvelables. Ces investissements concernent le remplacement d'éléments de construction ou d'installations vétustes et l'adjonction d'éléments de construction ou d'installations dans des bâtiments existants. Si les mesures sont subventionnées par la collectivité publique, le contribuable ne peut déduire que les frais qu'il assume lui-même. Le taux de déduction est de 100%.

Source : Règlement sur la déduction des frais relatifs aux immeubles privés (RDFIP)

Other works in Pully

Solar water heating in nearby towns