Make informed decisions when buying a solar energy system

Solar energy systems are good – that is undisputed. It is important to be able to base your purchase decision on a solid foundation.

Know what matters

When deciding to install a solar energy system, a number of criteria play an important role. The following is an overview of these criteria. Find out how you can have them automatically evaluated for your solar energy system at no cost.

Criterion 1: Own consumption

Criterion 1 is not the price – but rather self-consumption. This is an important factor when deciding on a solar energy system. Self-consumption is the electricity generated that you use directly in your own home. As a rule of thumb, the higher the self-consumption, the higher the savings potential with a solar energy system. This is because the electricity used in your own home is the most valuable electricity. Purchased electricity from the power company is expensive compared to self-produced electricity. Therefore, self-consumption significantly influences the economic efficiency of a solar energy system. Find out everything about cost-effectiveness

Criterion 2: The suitability of the location

The price of solar modules has fallen sharply in recent years and has now bottomed out. That is why the location of a solar energy system has become less important. In the past, the rule was: exact alignment to the south at an inclination of 30°. That is a thing of the past. Find out everything about the current state of the art here. Today, east- and west-facing roofs in all imaginable angles are just as interesting, if not more so. The advantage of east-west installations is the consistent production of electricity throughout the day. Even north-facing roofs can now be considered for solar installations – especially if the inclination is not too great or if a complete renovation of a roof is pending. This is because then including a north-facing roof can lead to large volume discounts on solar module purchases.

The east-west solar plant ensures a steady production of electricity throughout the day (picture: Megasol Energy Ltd.).

Criterion 3: Electricity yields and independence

The electricity yield is one of the most important criteria of all – it is the ‘income’ from the solar installation. The electricity yield is measured in kWh (‘kilowatt hours’). This is the same unit that appears on your electricity bill, except that with a solar installation you earn money with it instead of paying for it. The electricity yield can fluctuate over the course of the year, depending on the location and orientation of the solar installation. Unexpected results arise with facade systems: while the electricity yield is lower than with roof systems in summer due to the vertical alignment, the opposite is true in winter. Due to the low position of the sun and snow on the roofs, facades usually produce more electricity in winter than roof systems. The independence in per cent can be calculated from the electricity yield and the self-consumption. In summer, this is usually well over 100%; in winter, the type of system (facade or roof) plays a decisive role.

Fundiert entscheiden beim Solaranlagenkauf Übersicht
The evaluated house with 6 residents can be completely self-sufficient over the course of a year (picture: solarapp.ch).

Criterion 4: Contribution to climate and environment

The environmental impact is just as important as the electricity yield. After all, the client is also concerned about the environment, in addition to cheap electricity and independence. The focus here is on the reduction in CO2 emissions, which are expressed in kilograms or tonnes per year. Embodied energy is also an important criterion. Embodied energy is the energy used in the production, transport, installation and dismantling of solar modules. Claims that a solar module requires more energy to produce than it can produce during its service life are false. On average, a crystalline solar module is ‘energetically amortised’ after about two years – that is, the grey energy is recovered after two years. You can find more information about the sustainability of solar installations here.

Criterion 5: The solar systems and products

The choice of solar system has a decisive influence on the electricity yield, grey energy, sustainability and costs of a solar energy system. Therefore, the evaluation of solar systems and products is of great importance. A solar energy system consists of three main components:

  • solar module
  • assembly system
  • inverters

Generally speaking, systems and products from domestic manufacturers offer better value for money. This is due to higher quality and reliability, and not least because of the guarantees that can be claimed.

Facade solar panels perform particularly well in winter, with high yields (picture: Planeco GmbH).

Criterion 6: The prizes

Prices vary greatly from provider to provider. It’s worth comparing. Don’t just look at the bottom right-hand corner, but also consider the services offered. In most cases, more than one solution is possible and different providers have different approaches. To get an idea of a price, simply start the solar calculator and design the solar system of your dreams.

Criterion 7: Economic efficiency

In addition to the other criteria, cost-effectiveness is important when deciding on a solar energy system. As a rule, solar energy systems not only make an ecological contribution but also generate interesting returns that exceed those of all other investment alternatives. Returns of 2-10 % are quite realistic. However, not all building owners consider a very high return to be important. In times of negative interest rates, projects with lower returns can also be interesting, especially when it comes to investing assets securely.

Obtain a solid basis for decision-making

Get the solid basis for your decision, which takes into account the most important criteria – the SolarReport. This report is a fully-fledged preliminary project and provides you with well-founded and balanced information. This allows you to make a reliable preliminary decision. Get the SolarReport now – to do so, simply configure your solar system directly on your virtual roof. You can then request quotations for your solar energy system from several independent professional solar installers in Switzerland. After that, you can make your final decision. It’s free, non-binding and straightforward.