Civil Engineering Reference
In-Depth Information
1 Introduction
Increased green house gas (GHG) emissions from fossil fuel combustion for power
generation and emission of halogenated substances from vapour-compression-
based refrigeration, air-conditioning and heat pump systems contribute signifi-
cantly to the global warming potential, worldwide. The increased concerns over
the energy security and GHG emissions among the world nations have paved way
for bringing out useful and breakthrough research efforts towards achieving the
energy conservation potential, in almost all the engineering systems. A possible
way of reducing the GHG emissions can be achieved by using environment-
friendly, energy-efficient systems and technologies.
In addition, the growing energy demands and environmental concerns worldwide
have provided impetus to the development of many energy-saving measures during
the last couple of decades, especially applied to the buildings sector. In recent years,
the architects, engineers and consultants related to the building services engineering
have shown great interest in planning, designing and developing energy-efficient
buildings that are either newly constructed or being subjected to the refurbishment.
The inherent vision lying behind the state-of-the-art technological advance-
ments taking place in the construction sector is to sustain the energy efficiency in
both existing and newly developed buildings on a long-term basis. The existing
building envelopes which may seem to be consuming more energy can be refur-
bished in such a way that the energy consuming elements of the buildings can be
upgraded towards saving the energy, considerably. It is in the hands of the design
engineers and architects, whose value-added efforts put forth in identifying and
implementing the proper and suitable energy management technologies in build-
ings, particularly in the case of refurbishment, would result in a substantial savings
in the energy being spent so far.
It is being made a mandatory requirement and task worldwide that the heating,
ventilation and air-conditioning (HVAC) systems to be installed in the imminent
building architectures must conform to the energy standards and have to be highly
energy efficient. This means that, the future constructions will definitely result in
the development of high-performance buildings. But, as far as the present energy
demand and the energy security issues are concerned, the existing buildings or the
building envelopes that are near to the refurbishment must also to be transformed
as the high-performance buildings, globally.
In the spectrum of a variety of energy conservative techniques being tailored to
make the building structures energy efficient, they still depend upon the primary
energy sources for enabling them to effectively function during the thermal load
demand occasions. In this context, a realistic question may arise in the sense that,
is it possible for a system to make itself function with literally no input energy or a
quantum of which is being supplied? This might replicate the case of a perpetual
motion machine of first kind, but this condition can be achieved by the other way.
Factually, when the HVAC systems are engaged in providing comfort to
occupants in indoor environments of a building through cyclic cooling and heating
