More than 10 years
of experience

We are a pioneering renewable energy engineering and installer in photovoltaic self-consumption that, since 2011, has been bringing savings to families and companies by installing solar panels on buildings. Our administration, engineering and in-house teams of installers allow us to offer our customers great savings and a high-quality product both in installed material and in the execution process; we make easy what seems difficult. Connect to the energy!


We are here
to help you


We accompany you
throughout the process


Leave your projects
in our hands


Qualified installers
and technicians


We won't leave your
project unfinished

Photovoltaic Solar Installations

We make the whole process of a self-consumption photovoltaic solar installation easy, we offer trust, proximity and savings with our own staff. Our services include from the initial personalized study, legalization of the solar installation with the administration and execution of the solar panels. After-sales is very important to us and we will always be by your side to resolve all those doubts, suggestions or ideas you have in relation to energy efficiency; in addition we also offer preventive maintenance contracts for residential and industrial installations. 

Steps to install
a PV system

At Bancells Ecotècnics we take care of the whole process including dealings with the public administration.

We will receive your contact request and call you in less than 24 hours to ask you for the necessary information to write your personalized study-budget.

We will send you a very complete study-budget where you can find out how many solar panels you need. We will indicate the material we will install, a detailed energy and economic study, and a turnkey budget.

Having received your personalized study-budget, we will propose a technical visit to your home where we can resolve all doubts, check the feasibility of the installation and explain the whole process step by step.

Once the estimate has been accepted, we will send you the contract for signature together with the first invoice which will be 50% of the total. This amount will cover all the jobs until you have your installation assembled, configured, with commissioning and you can view it on your mobile phone.

Although the aid funds are exhausted, the registration lines remain open until December 31, 2023. We will register the application and your file will be on a waiting list.

We will draw up the technical design report that includes all the necessary sections for the future legalization of the solar installation and the request for the prior communication of works. From our administration department we will take care of all the formalities, you will only have to delegate the representation to us.

Once the prior notice of works has been registered and the corresponding taxes have been paid, we will propose a date for the start of the installation of your solar panels. Jobs usually take between 2 and 4 days, depending on the number of plates. At the end of the installation we will explain what we have done, we will create the user so that you can access your solar plant and we will invoice the 2nd section of the project which corresponds to 40%.

We will legalize your installation so you can offset the surpluses. At the end of the legalization we will apply for all the tax credits in force in your municipality, especially the IBI and the ICIO.

The last invoicing installment corresponds to the remaining 10%, and we will send you the invoice when you can download all the documentation from your client area that you will have to follow the progress of the project.

We will close the enforcement file but we will continue working. After-sales service is very important to us, and if you have any questions or need a maintenance contract, we can continue to help you.


At Bancells Ecotècnics, a renewable energy installer, our installations and projects speak for themselves:


They have already embraced renewable energies.


Frequently Asked Questions

Here you can find the information you need. If you have any questions, please contact us!

The connection of the solar system to the internal network of the building saves electricity from those kWh that are generated thanks to the solar panels and, therefore, do not have to be imported from the distribution network and are not registered at the electricity meter.

Two textures can be given. The first is that the production of the plates is higher than the instantaneous consumption of the building, in this case the difference (called surplus) is exported to the distribution network for its compensation in the electricity bill (discount in the energy term of the invoice); the second tessitura is that the production of the plates is lower than the instantaneous consumption of the building, and in this case work is done in parallel between the solar installation and the distribution network.

Add that, in the first tessitura, you can choose to install a battery, which would mean increasing savings and storing these surpluses to use when there is no production. Once the battery is full, the surplus will continue to be sent to the distribution network.

Els veïns que vulguin participar en aquesta metodologia han de repartir-se els kWh generats sota uns coeficient de repartiment, de forma que a cada veí se li descomptarà a la seva factura d’electricitat els percentatge dels kWh produïts que han acordat en reunió de comunitat de propietaris.

Si un veí té un consum més elevat que un altre no és un problema ja que tant el veí que consumeix més com l’altre se’ls descomptarà el percentatge que els hi pertoca, ni més ni menys.

The virtual battery is a concept that some marketers apply within their range of products. The current rule states that surplus compensation is a monthly record, not an annual one. This can mean that if the energy term of the electricity bill is less than zero, they would be giving away kWh to the electricity distribution company (usually happens in extremely oversized installations) . The virtual battery means applying a price to these kWh called uncompensated surpluses that the marketer will reserve in euro format to be able to discount later (for example during periods with few hours of sunshine). The problem becomes when this piggy bank only grows and shrinks very little, it would mean that the customer is losing money indirectly. Sooner or later this virtual battery will be canceled or disappear and it will be necessary to know how this money is managed.

However, the long-term solution is physical batteries.

Although it is detailed in the personalized study-quote you will receive, the plates we install offer a 25-year warranty for both production and mechanics, at the end of the installation you will receive a personalized certificate of these plates with the numbers of the plates installed in your home.

In relation to the inverter it varies depending on the brand to be installed. For example, Huawei offers a 10-year warranty, while Enphase offers 25.

As a rule, our installation work must be guaranteed for 3 years. However, and thanks to the experience in the sector and the good quality of labor with our own staff, we offer a guarantee of 5 years, two above the norm.

We are Technical Architects and we know the structure and construction processes of buildings. We apply a technique that prevents the entry of water through the holes made in the roofs. We always make these holes on the roof tile, never on the roof tile; the hole is sealed with a pressed elastomeric rubber that prevents the entry of water and, above this anchorage, the solar plate circulates. It is impossible for water to enter through this hole.

On flat roofs we usually install a self-supporting structure, thus avoiding drilling the waterproofing sheet.

The answer is no. For safety reasons, all solar inverters for instantaneous self-consumption must be stopped in these cases. Now, there are devices on the market that allow you to reactivate your installation in these cases, but a battery is necessary for the installation of plates.

The current law allows this to be done in two different situations:

  1. In the event that the customer is a self-promoter of works and is building or renovating the house under a municipal works licence. This home must be a regular residence and cannot be rented and/or sold.
  2. As long as and when the following conditions are met (all of them):
    1. The customer is an individual and not an entrepreneur or freelancer.
    2. The reform and/or construction of the house must have a final work certificate 2 years before the solar installation.
    3. The ratio between the total budget of the installation and the material of the installation itself should be a maximum of 40%, with the remaining 60% being execution labor.

It is a regulated self-consumption methodology within the RD244/2019 standard. In a generic way, it is about distributing the generation of electricity between several neighbors. In the electrical circuit of the solar installation, an Endesa-approved meter, called a generation meter, must be added, which will record all the kWh of the solar installation. Neighbors who wish to participate in this methodology must distribute the kWh generated according to distribution coefficients, so that each neighbor will be deducted from their electricity bill the percentage of kWh produced that they have agreed upon at the community meeting of owners

If one neighbor has a higher consumption than another it is not a problem since both the neighbor who consumes more and the other will be deducted the percentage that belongs to them, no more and no less.

It consists of deducting a percentage of the solar installation budget from the individual INCOME statement. This percentage varies depending on the reduction of primary energy in the home where it has been installed. To be able to calculate this energy reduction, two energy efficiency certificates are necessary, one before the installation and one afterwards; it must be borne in mind that the computer program for energy certification only takes into account electricity consumption for air conditioning and domestic hot water generation; therefore, if these two installations come from an energy source other than electricity, it is very likely that the reduction percentage will not be reached and, consequently, it will not be possible to de-tax the solar installation in the RENTA .

At Bancells we can advise you on this situation and indicate beforehand whether you could achieve this energy reduction.

These are rebates on two municipal taxes. The first corresponds to the Real Estate Tax (IBI) which varies depending on the Fiscal Ordinance of each City Council. This bonus is requested once the installation of plates is legalized, and the request consists of registering an instance at the Town Hall of your municipality. Be patient because they usually respond quite late.

On the other hand, the Construction, Installations and Works Tax (ICIO) is usually subsidized by 95%, having to be applied for together with the registration of the previous communication of works. Depending on the municipality, this bonus is applied immediately, but the vast majority is later, having to pay the entire tax and then request its refund.

The roofs of multi-family buildings are part of the outer skin of the building and are therefore communal, regardless of whether it is a flat or inclined roof. In the case of flat roofs assimilated to terraces of the last homes, it is necessary to know the constitution of the community of owners and to know whether these elements were deeded as communal for private use or private property of the home in question.

In any case, a meeting of neighbors is necessary for the installation of solar panels on the roof of the building and the resolution must be approved by a simple majority (those attending the meeting +1).

This statement is true. The plates are connected in series, therefore if one is in the shade its working voltage will be reduced, reducing at the same time the rest of the same circuit. However, there are technical solutions that allow you to minimize or avoid these effects, such as shadow optimizers. These devices force the inverter to work individually on the plate that is connected, so that it is separated from the rest of the circuit and does not affect the general production.

On the other hand, there are micro-inverters on the market. These devices are small inverters that are installed behind each solar panel so that the entire solar field works individually. Depending on the type of installation or cover it is recommended, but it is not recommended to always work with these devices, because in cases where they are not necessary the project has an additional cost that could be avoided.

The topic of sizes has always been a taboo when it comes to talking about it, luckily in solar photovoltaic it is very different. The efficiency of a solar panel is measured by the solar radiation in W/m² that it receives from the Sun, this efficiency is measured in %. Currently, the high efficiency plates are those that offer approximately 20-21%; considering that a 500W plate has a very similar surface to a 410W it is very likely that both plates have similar efficiency.

In this sense, a higher efficiency of the installation will not be obtained by more solar panel power. What’s more, working with large-sized solar panels (500W-550W-600W) can become a logistical problem for your installation and the space they occupy; at the same time it is a dangerous overload for the installer who has to move a surface of more than 2m² on an inclined plane.

In the end what you need is an installed power that fits your demand, therefore in this sense a smaller size does not mean less efficient.

In the last two years, solar installations in homes have skyrocketed and many operators have taken advantage of this ‘boom’ to enter the market, including banking, insurance and oil companies; many of these operators offer a lower price (up to points that are cause for concern) because they also reduce the price in the quality of material or subcontract unskilled labor obtaining a very cheap solar installation but surely the its useful life will be less than 25 years.

A photovoltaic solar installation is still an investment that, at least, must have a useful life of 25 years, and here many external factors come into play apart from the material, and it is the installer himself, so the quality of a work not only the material itself but also how it has been executed.