New Trends - Comfort Control in Buildings - page 228

tioned previously lie in the use of a horizon which allows us to obtain a major cost
reduction, (Agüero et al. 2013a ).

6.4 Suggestion for Building Technicians

Nowadays, the considerable increase in energy consumption and greenhouse gas
emissions is a problem of great concern, which should be dealt with in an appropriate
way. In addition, as discussed in Chap. 1 , energy consumption of buildings represents
approximately 40% of the total world energy consumption, mainly attributed to
HVAC systems, and moreover, they are also responsible for approximately 35% of
CO 2 emissions (IEA 2008 ). Furthermore, it has also been taken into account that
people develop most of their daily activities inside buildings, and thus it is necessary
to look for a tradeoff between users' comfort and energy efficiency. Nevertheless,
as illustrated in Chap. 3 , in spite of the large number of worldwide environmental
regulations, the design and construction of bioclimatic buildings and the increase of
energy efficiency in buildings climatic refurbishment, there are several factors which
can affect the performance of a building, such as the typical climate where it is
located. In these cases, it is necessary to combine the use of bioclimatic architecture
with the development of appropriate control architecture oriented towards providing
comfortable environments with minimum energy consumption. Therefore, in this
section, several suggestions for building technicians who want to develop comfort
control techniques inside them are provided. These suggestions are mainly based on
the experience acquired during the development of the works presented in this topic.

• Selection of comfort indices . Most of the work related to thermal or indoor air

quality comfort develop temperature or CO 2 concentration control approaches to
assure users' comfort. However, in the case of thermal comfort control, there
are many indices in the literature that provide accurate estimations of ther-
mal comfort sensation as a function of several measurements, such as indoor
air temperature, indoor relative humidity, mean radiant temperature, indoor air
velocity and so on. Some of these indices are the PMV index and the Givoni
diagram. However, to use these indices it is necessary to have a wide sen-
sor network which, in some cases cannot be accessible in a typical building.
Therefore, the selection of comfort indices is a process strongly related to the
necessities of the users of the building and the available resources. Hence, to
develop an appropriate room-level control approach it is advisable to have an
indoor temperature sensor, an indoor relative humidity sensor and a CO 2 con-
centration sensor. Besides, from an energy consumption point of view, it would
be recommendable to also have a presence sensor which provides information
about the occupation of the room. Furthermore, in reference to the automatised
control mechanism, it should be ideal to have automatic windows and blind
aperture/closing systems and an HVAC system with several degrees of freedom,
as in the case of the CDdI-CIESOL-ARFRISOL building in which the user can