The solar thermal installations consist of a set of components that collect solar radiation and directly convert it into thermal energy and then transported as a fluid to be efficiently stored for later use. This system works along side a conventional auxiliary system and may or may not be integrated into the same installation.

The elements of the solar heating installation for hot water are:

• A solar collection system made up of the solar thermal collectors which transform the radiation into thermal energy, heating the working fluid circulating these.
  
• A storage system (one or several tanks) storing the hot water until it is used.
  
• A hydraulic circuit, pipes, pumps, valves, etc. designed to move the hot fluid to the storage system.
  
• An exchange system that transfers the thermal energy from the collection system to the hot water for use.
  
• A regulation and control system that ensure the equipment is functioning correctly to provide the maximum solar thermal energy as possible and to prevent various potential environmental situations (overheating, freezing, etc).
  
• An auxiliary conventional energy unit to guarantee a supply of hot water when there is very little solar radiation or the actual demand is greater than the estimated demand.

These installations are included in Spanish Royal Decree 314/2006 of 17 March, in the Technical Building Code (TBC) with the prime objective being that of making buildings safer and more energy efficient; the Basic Energy Saving Document makes it compulsory to include energy efficiency criteria for new and renovated buildings. Five basic energy requirements must be considered:

MP garantizará al sector de la vivienda el suministro de los equipos y una ingeniería basada en la capacidad, la durabilidad y la calidad

• Limited energy demand (Limit values for the building designs).
  
• The solar thermal installations to satisfy the heating requirements of the occupants.
  
• Energy efficiency of the lighting installations.
  
• Minimum contribution from solar power systems requiring between 30% and 70% of domestic hot water to come from solar thermal energy depending on the estimated daily volume of the hot water demand and the climate of the area in which the building is located.
  
• Minimum photovoltaic contribution of electrical energy.
  

Based on an estimated average of 450,000 new housing constructions adopting this measure and over an appropriate timeframe from the first construction projects affected by the regulation and effectively being implemented, it is thought that a total surface area of 2,500,000 m2 will comply with the TBC by 2010 when the Renewable energy Plan is complete.

The TBC acts as a promotional tool able to pilot the launch of the sector until the objectives of the Renewable Energy Plan are achieved (4,900,000 m2 to be installed by 2010). The objective can be achieved provided that the technical/economic consensus of the developers, architects, manufacturers and installation technicians/maintenance team also meet their commitments.

In this context, the Renewable Energy Area of MP’s Engineering, Services and the Environment Division will show its support for the housing sector by supplying equipment and engineering based on the capacity, sustainability and quality of the installation as well as an effective after sales service. As well as MP’s installations helping to meet the objectives of the 2010 Renewable Energy Plan, they will also be a point of reference for society due to their efficiency as an element that allows the rational use of energy and reduces the consumption of traditional energy sources. All of this is achieved by using a renewable energy source.

Íñigo Argüeso Bejarano
Director of the Renewable Energy Division. Renewable Energy Area