Frequent questions

Questions About Solar Energy

Questions about solar energy

Solar energy is a renewable energy source that in recent years has gained considerable strength as an alternative to fossil fuels.

The simplicity and advantages of solar energy offer many installation possibilities to small producers. However, before considering the feasibility of such an investment, many questions about solar energy may arise.

Below we will try to resolve some of these doubts.

Are Solar Thermal and Photovoltaic Installations Compatible?

Photovoltaic modules capture photons from sunlight and produce electricity. Solar collectors take advantage of solar heat to obtain sanitary hot water. In the same installation, both solar energy systems are compatible.

Hybrid solar panels can also be installed. Hybrid panels are composed of photovoltaic cells but also take advantage of the thermal energy of this energy source.

How Long Does It Take to Pay for a Solar Installation?

There are different factors that determine the payback period of an installation:

  • The correct calculation of the needs of the solar installation.

  • It depends on system optimization.

  • The proper installation and quality of materials

  • The public subsidies obtained.

  • The use that is given to solar panels. 

  • The schedule of solar radiation during the year.

  • The climate of the area where the solar array is going to be placed.

On average, thermal installations are amortized approximately after 4–6 years. In turn, photovoltaic installations are amortized after 7-9 years.

What Is the Useful Life of a Solar Installation?

In the case of solar thermal systems, solar installations have a life span of more than 25 years. 

In the case of photovoltaic solar plants, the life span is greater than 30 years. 

What Is the Relationship Between the Amount of Sun Received and the Yield Obtained?

Solar cells don't just capture solar radiation on clear days. The diffuse radiation that exists during cloudy days can also be used, but at a lower yield.

It should be noted that the electrical current is generated from solar radiation, not heat, therefore cold does not represent any problem for photovoltaic use. In fact, like most electronic components, photovoltaic panels work more efficiently at lower temperatures, always within limits. 

Does Solar Energy Affect Climate Change?

Solar-generated power does not affect climate change directly. The use of solar panels does not emit greenhouse gases. In addition, being renewable energy it does not consume natural resources. It is considered to be clean energy that does not harm the environment.

However, the manufacturing processes of the components of a solar installation do cause the emission of harmful gases.

Are Solar Panels Compatible with Electric Generators?

Yes. The production of electrical energy by photovoltaic modules is variable. There may be cases that require an electrical power that the panels are capable of offering. In these cases, electric generators make it possible to produce the energy that is needed.

Hybrid solar systems are solar systems that are supported by another energy source. This source can be electrical generators or wind turbines (wind energy).

How Should the Solar Panels Be Placed?

Solar panels work best if they are placed in a place where they receive full sunlight. They can be placed on the roof of a home or office, on a supporting structure, mounted on the facade or on the ground. As panel installers are aware, it is preferable to avoid places that receive shade at least during the central hours of the day. 

The ideal inclination of the panels varies depending on the latitude in which we are. Normally 45° are used in thermal and 30° in photovoltaic facing south.

How Should the Solar Panels Be Attached to My Roof or Roof?

There are different ways, the fastest, most comfortable and used is by means of aluminum structures, which weigh little and have accessories for fastening to the terrace or to the roof.

The adjustable is used on flat surfaces or on roofs with little inclination. It has secure parts to hold the plates and a polyurethane sealant or adhesive already incorporated in the kits is then used to seal the fasteners on the roof and thus avoid any water leakage.


What Is the Maintenance of a Solar Installation?

Solar installations require minimal maintenance, and of a preventive nature. That's mainly because solar panels have zero moving parts to break. Two aspects to take into account are:

  • Ensure that no obstacles cast a shadow on the panels

  • Keep the panels clean, specifically the faces exposed to the sun

In the case of solar thermal energy, it is necessary to be careful with low temperatures to avoid freezing of the fluid. In the case of long periods of inactivity of the solar installation, it is necessary to avoid that the fluid reaches a too high temperature.

Should the Solar Panels Be Constantly Being Cleaned?

It is enough to wet the glass surface with water once a year. For example with a hose, (2 times in places with very little rain) to remove the dirt from bird waste, as well as branches or leaves that have arrived from neighboring trees.

Does Solar Energy Work When It Is Cloudy or Not?

Yes, the solar array continue to work since a significant amount of ultraviolet light filters through the clouds, and a small part in this case from diffuse light. Panel performance of up to a maximum of 50% should be calculated in these rare and sporadic seasonal cases.

Solar or Isolated Solar Self-consumption, Which Way Do I Decide?

If you have a home without electricity an isolated kit would be a good option. It is also called an autonomous solar kit.

You can also decide on an isolated solar energy kit in homes connected to the grid. In this way, you would avoid having to pay the line maintenance fee every month ad the kilowatts consumed.

For its part, solar self-consumption should be aimed at those who already have electricity in their home,saving on electricity bills.

How Much Space Do I Need to Install a Photovoltaic Panel?

The space we need for the photovoltaic solar installation will be imposed by the amount of electricity we need or want to generate. Knowing that each panel is capable of producing a certain amount of electricity, we will divide the total electricity we need by the amount of electricity that a solar panel can produce. Therefore, we will obtain the number of plates that we will need.

Returning to the data of that panel, we will have to multiply its size by the number of panels that we have calculated before. This way we will have the minimum sufficient surface, placing them all together on the ground. But we must take into account if we are going to give them an inclination, to calculate the ideal corridors between the plates.

How Is the Number of Solar Panels Calculated?

To calculate the number of solar panels necessary for a photovoltaic system, we must take into account multiple variables such as:

  • The type of installation (with batteries or without batteries)

  • The peak sun hours of the place

  • The consumption of the house

  • And finally, the money savings you want to get …

The goal is to avoid that we spend more money buying the system and with tax credits than that we save reducing electric costs. Therefore, it is imperative that the system size is well-dimensioned.

Can You Heat Water with Photovoltaic Panels?

Generally, in the solar energy sector, thermal solar panels and photovoltaic solar panels differ. A thermal solar panel is designed to effectively heat water, while a  photovoltaic solar panel is designed to generate electricity.

It is true that with proper conditioning, for example with an electrical resistance connected to the photovoltaic panels and inserted into a water tank, they can also have this function, although it is not the most common.

How Much Will I Really Save on My Electricity Bills Every Month?

The money savings depends on how much electricity your home or business uses. Plus, where you live, the rate your utility company charges for electricity, and several other factors.

Concerning to saving money, most solar companies aim to offset 70–90% of your monthly electricity bill.

What Is the Best Option for Installing Solar Panels with My Budget?

The price of installing a solar array is low. You will qualify for tax incentives and rebates. Once it is installed, you will receive lower electricity bills.

In addition, you can try to get a loan to finance your solar system.

Another option is a solar lease. This will allow you to make the switch to solar without big initial costs.

What Is Net Metering?

When you produce electricity, the installation will be an electric meter that does two functions:

  • It will show the energy consumed when solar panels aren't generating electricity (like cloudy days or at night)

  • It will show the electricity generated during the day by the solar array.

The amount of electricity you produce and you are not going to use. You can sell all this solar-generated power again to the company.


Published: December 10, 2009
Last review: September 6, 2020