efficiency

Indoor air quality in residential buildings has been attracting more attention from the public. Many portable air cleaner products have been developed and are available in the market. Manufactures generally claim that those portable air cleaners can efficiently remove PM2.5 and/or TVOC and can also remove virus from the indoor air. However, no standards are available to have the claimed efficiency comparable and thus unclear effect in applications at homes.

Heat recovery ventilation (HRV) is one of the usual techniques (next to demand controlled) to reduce the energy impact of ventilation in buildings. For a given air change rate, the energy savings of HRV are in the first place dependent of the heat-exchanger efficiency, usually measured in standardized laboratory conditions. However, many other factors can have an impact on the overall system performance in practice.

Air curtain assisted range hoods are very customary in large industrial kitchens. They allow to increase the capture efficiency of the range hood while lowering the net exhaust flow rate. For applications in residential settings, there is a lack of data on the performance of air curtain assisted range hoods, as well as a lack of information on the required settings and boundary conditions to come to the successful application of air curtain assisted range hoods.

The present study aimed at assessing six commercially-available in-duct air cleaning devices which are designed to be mounted in the central ventilation system of offices or commercial buildings. The selected devices use different air cleaning technologies: mechanical filtration, electrostatic precipitation, gas filtration, ionisation / cold plasma, photocatalytic oxidation (PCO) and catalysis under UV light.

Building integrated renewable energy sources e.g. photovoltaic system is one of the promised solution for improving energy efficiency in building. However such kind of the system is restrained by irregular power supplied and necessity to convert current from direct to altering form. Therefore, very often the electrical energy generated by photovoltaic system cannot be effectively utilised to supply building devices, e.g. components of HVAC or lighting system.

The paper presents optimization model of the chilled water based data center cooling system. The optimization procedure includes system technological and mathematical model, limiting conditions and optimization criterion, which in this case is annual power consumption minimum. The cooling system model is defined by constant parameters and decision variables and consists of aircooled chiller, independent external freecooling heat exchanger (drycooler), computer room air handling unit (CRAH) and constant flow chilled water system with circulation pump.

Using solar thermal energy is an interesting option for heat driven air conditioning e.g. desiccant cooling, but it is very important to know with which efficiency this renewable energy is used. In this paper a solar installation of direct flow vacuum tube collectors dedicated for desiccant cooling is investigated. First a model of the mentioned collectors is presented and implemented into the simulation environment SPARK then it is validated experimentally. After, simulations of autonomous operations are run and the global efficiency is calculated.

The use of electricity in buildings constitutes around 16% of Singapore’s energy demand. To incorporate energy efficiency measures is one of the key mission to ensure that the economy is sustainable. The recently launched building energy efficiency labell

This presentation will make the audience aware of the importance of ISO-recognized certificationprograms in the testing adjusting and balancing and commissioning of HVAC systems. ImportantISO 17024 standards will be covered as well as their importance. Many faults have been found inexisting testing adjusting and balancing and commissioning certification programs ranging fromconflicting issues within the organization and their testing procedures; political control over theprocess; inconstant certification methods; geographical differences.

The mixing of different air streams is a process commonly found in air handling systems. One of the most common examples of this process is found in the air handling unit mixing box where outdoor air is mixed with return air. In the adiabatic mixing process, the energy leaving the mixing box equals the energy entering the mixing box. In order to calculate the energy in the mixed air stream, it is only necessary to know the energy in the outdoor and the return air streams. As a result, it is not necessary to consider whether the mixing process is ideal or not.