Repsol YPF

Since 29 March 2007, the provisions of all the documents making up the CTE must be applied, leading to a surge in renewable energies due to the progress that this will imply in the installation of both thermal and photovoltaic solar panels. 

Although it is true that the cost of housing is to go up between 0.7% and 1%, depending on the type of building, the additional cost will be compensated by a reduction in consumers’ electricity bills, estimated to be between 30% and 70% for hot water due to the energy supplied by solar panels. Furthermore, there are subsidies for installing solar panels on buildings which are being renovated and new builds in the majority of autonomous regions. Anyone can invest in solar energy and become an energy producer.

Profitability 
The equipment for using solar energy is technologically viable and profitable. Investing in solar panels also pays for itself with the savings that are made.

There are two kinds of solar panels: thermal panels, which use the heat from the sun to heat the water for different uses, and photovoltaic panels, which transform sunlight into electricity. In order to decide which of the two options to go for, it is advisable to carry out a small study of the needs of each building. Both are impermeable, as such they can be used as a covering material. In the case of photovoltaic panels it is very important which way they face. There are also procedures to make the solar roof adjustable by turning a set of panels. 

Any solar installation must have an extensive guarantee period that ensures that all the elements efficiently achieve the purpose for which they are designed. Panels are estimated to last over 30 years. Although installing them is not compulsory, due to their profitability it could be interesting to study the possibility or at least have them pre-installed, in other words leave everything ready to install panels in the future.

The systems are different depending on whether they are for hot water, swimming pools or heating. There are flat and vacuum panels, dual pumps for alternative operation, accumulation tanks with anti-corrosion protection, heat exchangers... Solar panels provide an interesting support mechanism for heating, especially heated floor systems. Nevertheless, thermal solar energy installations almost always require the support of conventional energy production systems, using gas, oil, etc. 

The CTE makes continual review plans compulsory, since without correct maintenance no energy production system would achieve an efficient result.

Environmental consequences
The heat from solar energy is now used in many buildings, particularly in Germany. The beneficial environmental consequences of this energy saving are estimated as: over 8200 tonnes of carbon dioxide per year will no longer be emitted for every 5000 dwellings which have this kind of technology. 

All kinds of buildings can use this energy, whether they are residents’ communities, individual houses or even companies. These systems are simple to install and they are becoming increasingly cheaper, not forgetting that they contribute to the concept of sustainable development. 

In Spain, there are already numerous engineering companies and companies specialising in installing solar systems which will advise each customer about the components and technologies which best suit their needs with the aim of ensuring optimum performance.