Abstract Mediterranean countries show two specific features regarding air-conditioning of buildings: a high—and growing—cooling load and high relative humidity, at least in coastal zones. In this contribution we report on the development of an innovative micro scale tri-generation system (power + heating + cooling), equipped with a rotor based desiccant system adapted to theMediterranean con-ditions which receives heat for the desiccant regeneration from a combined heat and power (CHP) cycle.22262
The paper presents the design of the advanced desiccant air handling unit which uses a high efficient combination of a vapor compression chiller working at a high evaporator temperature and a desiccant wheel (silica gel). The electricity of the chiller is sup-plied by the CHP system and the heat to regenerate the desiccant is the waste heat of the CHP. System simulations have been used to optimize the hydraulic design and the operation strategy in order to minimize operation costs and maximize energy savings. Some new component models, e.g. for the advanced desiccant cycle were developed for this purpose. The final design of the entire system consisting of the CHP system, the vapor compression chiller, the advanced desiccant air handling unit and the load system is described. The load system is composed of an air duct network with induction units and a chilled water network with fan-coils in the office rooms.
Regarding energy performance results indicate an electricity saving >30% in comparison to state-of-the-art solutions based on conventional technology.
2005 Published by Elsevier Ltd.
1. Introduction
Air-conditioning of buildings is a promising applica-
tion of co-generation systems during summer. For this
purpose thermally driven equipment to supply cooling
driven with the co-generator waste heat has to be em-
ployed. The most widespread technology used for thispurpose is based on heat driven water chillers such as
absorption chillers (e.g. with the material pair lithium-
bromide–water) or adsorption chillers. Water chillers
are used in combination with different techniques to
purge cooling loads from the rooms such as e.g. fan-coil
systems, chilled ceilings or centralized air handling units
(AHU). However, in order to treat latent loads, air has
to be cooled below the dew-point when chilled water
systems are used. Thereby the air is cooled far below
the temperature level needed for comfortable indoor
conditions and consequently the chiller works at a
COP lower than if employed for sensible cooling, i.e.
temperature control, only.An alternative to treat latent loads by cooling air be-
low the dew-point is the direct treatment of ventilation
air in an open sorptive cooling cycle, also referred to
as desiccant cooling system. In such a cycle air dehumid-
ification is realized using a sorptive component such as a
sorptive wheel. Additionally, a temperature decrease can
be achieved by combination of the sorptive dehumidifi-
cation with either direct, indirect or combined (direct +
indirect) evaporative cooling.
However, the standard desiccant cooling cycle, which
is for instance installed in temperate climates like Cen-
tral Europe, is not able to cope with the conditions of
warm and humid climates such as for instance in the
coastal zones of the Mediterranean countries. Therefore
application of desiccant technology in such climates
using sorptive rotors requires specific configurations.
In the framework of the project MITES (‘‘Micro Tri-
generation System for Indoor air conditioning in the
Mediterranean Climate’’), a project supported by the
European Union, a novel configuration of an open cool-
ing cycle based on sorptive rotor technology has been
developed. This heat driven air handling unit receives 室内空调英文文献和中文翻译:http://www.youerw.com/fanyi/lunwen_14819.html