energy savings

The aim of this work is to study the influence of global heat transfer coefficient (Utot en W/m2.K) of the opaque walls (walls and roofs) and of the glazed walls (bays) on the annual consumption of heating, cooling and overall consumption energy. We analyze the number of hours of heating and cooling under operation with partial load and full load. Profiles of indoor temperatures are also given. The work is established on several office buildings defined according to a typology built within the framework of a study on energy savings in air-conditioned office buildings in France.

In this paper "the ventilability chart" concept is presented and the methodology for drawing it for whatever space is illustrated: its aim is to check the effectiveness of natural ventilation in ensuring comfort levels related to the indoor air quality.Three case studies of calculation of air exchanges by naturally ventilation in typical office room are presented.Through the ventilability charts here proposed, it is possible to determine the conditions under which natural ventilation can be properly used instead of mechanical ventilation.

It is common that the first cost is the main criterion when making choices between differentsystems. However, it is possible to demonstrate that a lower initial investment can turn out tobe more costly from the whole life-cycle viewpoint. With life-cycle cost (LCC) calculations, itis possible to get a better overview of the total cost. LC costs of typical systems (fan-coil,constant airflow rate, variable air volume and ventilated beams) were analysed and comparedin a case-study office building.

For energy savings, DCV systems are more and more used in ventilation systems but toestimate their energy savings, variation of occupation in the building (in time and number ofperson) must be estimated. We have enquired on real occupation on site in 27 offices and 13meeting room in France. Occupation rates have been monitored either by webcam or byenquiry to the users. Results show very low occupation rates in meeting rooms although mostpeople feel they are very occupied. Yet effective time of meetings and number of occupantsare less than expected.

The peak electrical demand of office building VAV systems will be reduced by about 1.2 Kw/1000 Ft2 by employing an Integrated Systems Demand Control Technology (ISDCT) sequence to reduce peak intake flow by about 56%.Supply, return, and exhaust fan energy decreases with reduced airflows and pressures; and chiller system energy is saved by reduced cooling coil loads.The ISDCT sequence continuously computes zone contaminant concentrations allowing compliance with reference standards.

The historical headquarter of Italian Ministero degli Esteri (Ministry of External Affairs) in Rome named as "Palazzo della Farnesina" is a very large (about 700.000 m 3 of volume) and complex multi-functional building.The objective of present study, commissioned by Ministry of Environment, is to evaluate different energy saving strategies in this building achievable by the implementation of retrofit actions. At first, the seasonal energy consumption obtained by the existing cooling and heating systems has been estimated.

This CD gives information to understand and apply the new French Thermal Regulations RT 2000, which are applicable to new residential and commercial buildings and which mainly concern the calculation of energy consumption of buildings and comparison with reference values.
The CD includes the official texts of the regulations, a slide presentation of the regulations, software tools enabling the user to make sensitivity analysis of the calculation results to various parameters of the building.

Describes the new regulations concerning the energy efficiency of buildings and ventilation requirements that have been adopted for Ireland.

This work deals with the characterization of the thermal performance of a LHS (Local Heating System) tested on 18 persons (9 males and 9 females) working in a real free-running office with mean room temperatures varying from 16C to 18C. Local heating systems investigated consist in a combination of two radiant panels and a foot heater. During the measuring tests, the metabolic rate, the tympanic and local skin temperatures were monitored.

This contribution reports on investigations about the performance of decentralised ventilation units with heat recovery. Such units can be easily installed in individual rooms and therefore offer an interesting alternative to central ventilation units. Nevertheless these units exhibit some problems. Experimental examinations of two commercial decentralised units showed that the real effectiveness of heat recovery was always below 50 % and that considerable leakage between the air ducts can result in poor indoor air quality.