【 Weak current College 】 on central air conditioning system and energy-saving---Power By 【 China power house network 】

Economic development, civil, public and business building in popularity of central air conditioner, have a serious problem of energy consumption. This article from the wall, air conditioning and heat source, the end of air conditioning, air conditioning water system and air conditioning management aspects raised a number of energy-saving measures and methods.

1, building envelope

Envelope, such as walls and the roof have been compared in buildings in General. Energy-saving doors and Windows from the following aspects:

1.1 control window wall than through exterior Windows build of heat consumption in occupies a total consumption of Gérard 35% ~ 45% in the guarantee under the premise of indoor lighting; reasonably determine ratio of the wall is very important. As a general rule all toward the window wall ratio shall not be greater than the following numbers: 25%; North East, 30% to 35% in the South.

1.2 improve hermetic room doors and Windows of ACH to minimize by 0.8h-1 0.5h-1 cold consumption of the building can reduce 8%, the design should be airtight good doors and Windows. Installing doors and Windows closed is to improve airtightness of important means. Closed should adopt a flexible sound, with strict, received a strong and durable products. Under Windows, using different seal. If rubber bar, plastic or rubber seal, the combination of its shape can be a bar or a flush. Available paste, packed tight or nail knot method fixed.

2. air conditioning and heating source

Central air conditioning energy consumption generally consists of three parts, namely, 1. air-conditioning heat and cold sources; 2. air-conditioning unit and terminal equipment; 3. water or air transportation system. This three-part, heat and cold sources in energy consumption energy consumption accounted for about half of the total energy consumption is the main content of the air conditioning energy saving. Following the ice thermal storage system to host energy-saving. Ice thermal storage system: building air-conditioning cooling load required when all or part of the preparation of non-use of air time, its energy-saving up for air conditioning. The system of the host that the change of total energy consumption is not great, but you can use electricity when low peak electricity, but smaller in height with or without power-balance power peak and Valley-Dutch, slowing the power plant and the construction of supply and distribution facilities, is a recommended method of saving energy. Use cool system, there are two ways to load management strategies can be considered. When the electricity price in different time differences, we can all load transfer to cheap electricity time running. You can choose one can save enough energy to cool the traditional cold water unit, will the entire load to go outside peak, known as "all energy system".

This approach is often used for rebuilding project using existing chillers, simply add a cool device and related auxiliary equipment, but be aware that existing chillers are applicable to ice storage system. This approach also applies to special buildings, large cold release required instantaneous, such as the gymnasium building. In the new building, part of the energy storage system is the most practical, is also an investment in effective load management strategies. In the load balanced approach, continuous operation of chiller, it at night for refrigeration and storage, use and storage in the daytime of the cooling capacity for the provision of refrigeration. Will run from 14 hours up to 24 hours, you can get the lowest average load. Required power costs significantly reduced and the chiller cooling capacity can also be reduced by 50-60% or more. By Hangzhou several projects such as: Construction Bank of China Hangzhou branch office building, Hangzhou new King Fuk department store of energy saving practice indicates that the system (economic indicators) in 25-35%.

3 airconditioning units and terminal equipment

Home-fan-coil and from looking at the overall level of similar foreign products compared to the same, but the comparison with foreign advanced level, the main difference is the power consumption, coil weight and noise. Therefore design necessarily to intended use light weight, unit fan power for cooling (heat) of larger units. Air conditioning units should be chosen unit fan, air pressure, air leak less matches, air transport coefficient of the unit. The following is the air conditioning unit of energy of VAV system: full air conditioning system design of basic requirements is to determine the air conditioning room transporting enough, after a certain deal of air to absorb more heat recovery and indoor humidity, thus maintaining indoor temperatures and humidity.

Its basic formula is:



Type L — air, m3/h;

Qq, Qx-air conditioning to absorb all the sensible heat hot heat recovery and heat, W;

Ρ-air density, kg/m3, desirable 1.2;

C — — the specific heat of air pressure, kj/kg ¡æ, desirable · C = 1.01;

In, is — indoor air enthalpy and blast State air enthalpy, kj/kg,

Tn, ts, — indoor air temperature and air temperature, ℃.