Solar thermal installation in Le Locle: a guide for owners

2 °C, presents a unique challenge for heating. The energy demand for thermal comfort is high, with heating degree days reaching 4007 Kj/year.

In this context, integrating solar thermal collectors helps reduce dependence on traditional heating systems, especially during months when sunshine is sufficient to cover hot water needs.

The ideal time to consider this work is when replacing your aging boiler or during a global renovation of the building envelope. By taking advantage of work on the distribution network, you minimize labor costs and optimize technical integration.

Anticipating this work allows you to smooth out annual energy consumption in a region where winters are long and harsh, thus ensuring better resilience against fluctuating energy costs.

The technological choice depends on the type of collectors : flat plate collectors, which are robust and suitable for summer hot water production, and vacuum tube collectors, which are more efficient in cold or diffuse weather.

In Le Locle, given the global irradiation of 1302 kWh/m²/year, sizing must be done by a professional to ensure optimal coverage without summer overheating. Solar thermal collectors generally cover a large part of the hot water demand in summer, but they require a precise study to ensure efficiency.

A common option is to couple the solar thermal system with a heat pump. This combination requires a rigorous sizing study. The installation must also include a storage tank capable of keeping water hot during less sunny periods.

It is essential to discuss with your installer the materials used for the pipes and the quality of the heat transfer fluid to withstand the extreme temperatures that the region can experience during harsh winters.

The real estate stock in Le Locle shows great diversity, ranging from old houses to more recent constructions. For buildings constructed before the 1990s, it is imperative to check for the potential presence of asbestos in insulating materials, pipes, or old boiler rooms before drilling or modifying structures.

A preliminary analysis by an expert is recommended to avoid any health risks when installing roof anchors.

Furthermore, the thermal insulation of the building directly impacts the performance of the solar system. A poorly insulated roof can lead to significant heat loss, reducing the efficiency of your investment. Also, check the state of existing distribution networks.

If your building is old, modernization of the pipes is often necessary to ensure that the heat provided by the collectors is efficiently transported to storage.

Finally, do not forget to check the characteristics of your roof: slope and south orientation are ideal, but older buildings may require structural reinforcements to support the weight of the collectors and the snow loads typical of the region.

In the canton of Neuchâtel, the procedure for installing solar thermal panels is simplified. For 'sufficiently adapted' installations on a roof, in the building zone and outside protected areas or objects, a simple notice to the competent municipal or cantonal authority is sufficient.

This procedure replaces the classic building permit. In general, this notice must be made about twenty days before the start of work, which offers some flexibility in planning your project.

However, caution remains necessary regarding built heritage. The municipal urban planning department provides procedures and documents related to solar installations. It is strongly advised to consult this department directly for your specific building rather than assuming a single rule for the whole city.

If your property is listed or located in a protected area, additional aesthetic or technical requirements might apply. Early consultation with local authorities helps avoid any subsequent administrative blockage and ensures that your project integrates harmoniously into the urban landscape of Le Locle.

The canton of Neuchâtel offers aid via 'The Buildings Program' for solar thermal energy. The amount of these subsidies is defined according to a current scale. The golden rule is to make your request before starting work: no aid can be obtained if the installation is already finished.

ch' to learn the precise conditions and submit your file.

Regarding taxation, investments intended to save energy are deductible. If the deduction of investment costs cannot be made at once without creating a negative net income, you have the possibility of carrying over these costs to the following two tax years (N+1 and N+2).

These costs must have been fully declared the year they were invoiced. Remember that the choice between the deduction of actual costs and the flat-rate deduction (10% or 20% of gross yield depending on the age of the building) is made each year and for each building.

If you opt for the deduction of actual costs, a clear split between maintenance and energy-saving investment is necessary.

The realization of a solar thermal project follows structured steps. The first phase consists of defining the energy requirement and technical feasibility with a qualified heating engineer. Once quotes are compared, you submit the grant application, an essential step before any commitment.

After validation, material ordering and roof preparation can begin. The ideal season for work is spring or summer, to avoid inconveniences related to the 107 annual frost days and the harsh winter weather conditions in Le Locle.

Once the collectors are installed on the roof, the connection to the storage system and hot water distribution is made. Pressure tests and commissioning are carried out to ensure there are no leaks and that the fluid circulates correctly. All these steps guarantee a lasting installation.8 °C.

The most common error is ordering work before receiving approval for cantonal financial aid. Ensure you have a detailed offer that clearly distinguishes maintenance costs from investment costs, as this is crucial for your tax return.

Do not neglect the sizing study, as an oversized system loses efficiency and increases unnecessary costs. It is also risky not to check the structural state of your roof before starting the site, as the weight of the collectors requires a solid framework.

Before signing a quote, verify that the installer has taken into account the optimal orientation and inclination of your roof. Ensure that the proposed materials withstand the climatic conditions of Le Locle. Check that the municipal notice procedure is included in the schedule.

Ask for a warranty on the installation and a clear explanation of how the system works. Finally, ensure that the quote includes the costs for commissioning and initial adjustment, ensuring that the system is optimized to meet your specific hot water needs.

A solar thermal installation is designed to last but requires periodic maintenance to ensure its performance over the long term. In Le Locle, significant temperature variations require regular monitoring of the quality of the heat transfer fluid, which can degrade over time.

A professional should check the state of the system every few years to monitor pressure and the integrity of hydraulic components. These simple interventions help avoid breakdowns and ensure constant production.

Durability also depends on use. In summer, if your hot water consumption decreases, the system can get very hot. It is important that your installer has provided safety systems against overheating.

Also, keep an eye on the state of the collectors; in case of dirt deposits or debris, a light cleaning may be necessary, especially after storms or heavy snow episodes.

Rigorous maintenance extends the life of your installation and maintains its energy efficiency, thus protecting your investment and actively contributing to reducing your CO2 emissions.