Do the photovoltaic modules have a negative impact on the aesthetics of buildings?
There are modules on the market that integrate perfectly with the architectural style of any building without lessening its beauty. The system may be highlighted or hidden. Also, installing a solar system increases the building's market value, even though it is a new constructive element which needs time for a good constructive and architectonic use.

Is solar energy too expensive to be used intensively?
Generally, the bigger the plant, the cheaper the cost per W installation is. For a large installation, there will be a reduced cost through the assembly, transport and simplified planning.
The Federal office of Energy analyzes the market constantly and publishes regularly the prices of reference systems. Here is a summary:
Price of reference installations in CHF/kWp

The integrated installations are generally 15% more expensive. However, in a new building, the integrated modules replace the tiles and thus allow lower costs.
It is observed that the prices keep going down, allowing today the use of solar energy on a large scale and at competitive prices.

Is the life of a photovoltaic module 20/25 years?
The life of a PV module does not end after 25 years: this is the reference period given by producers for the guarantee of 80% of the module's initial power. For example, the first  grid-connected plant in Europe was installed in 1982 at ISAAC and has lost only 20% of its power.
Quality is an important factor in the life of a plant. The photovoltaic modules installed in the system must be electrically and mechanically safe for the entire expected life of the plant. The Swiss Photovoltaic (PV) Module Test Centre is an ISO 17025 accredited testing laboratory specializing in the field of electrical and mechanical characteristics of photovoltaic modules.

Is PV performance a limiting factor?
This statement does not consider other factors that determine the choice of a PV system. Yield is often described as the delivered power referred to 1m2 [W/m2], but for the owner of the plant it is more important to consider the produced per installed power (kWh/kWp). Yield becomes aless relevant factor if the available area is large enough to satisfy the owner's requirements, for example a partial or total coverage of the annual consumption. To better illustrate this prejudice it is useful to recall that a low consumption light bulb, used every day, has a yield of only 10%.

Does manufacturing, installation and recycling of a photovoltaic system require more energy than the energy produced by the plant during its life?
Many studies have proven otherwise. One of thesse was carried out by Hespul with the support of Ademe for the OECD member states and with the support of European organizations (link). In this study, the swiss example was Bern.
Before discussing the results, it is essential to give a definition of Energy pay-back time. Energy pay-back time is the time in years required for a complete PV system (modules, cables and electronics) to produce the energy used for its production. The study highlighted that for a crystalline technology system installed in the city of Bern, the energy pay-back time ranges from 2.5 to 4 years. The time depends on the position of the PV plant. Indeed, if it is set on a roof, thanks to its tilt, it annually receives more solar energy that one located on the facade.

How and where are PV modules disposed when they no longer produce energy?
Swissolar, the professional association for the swiss solar energy, and SENS eRecycling have signed a cooperation agreement that from 1.1.2014 will govern the main aspects of the recovery and disposal of photovoltaic modules in Switzerland.
Swissolar and SENS eRecycling have regulated the collaboration through a contract mantle. The latter serves as the basis for individual contracts, which in a second step SENS eRecycling will stipulate with members of Swissolar. It covers the affiliated companies that manufacture or import directly photovoltaic modules. The financing of recycling will be secured by an in advance recycling fee (TRA). Details: Recycling