Investors and system managers are always looking for ways to reduce energy consumption and costs. The HVAC system in the hotel is always the most energy consuming part.
Therefore, if this system operates with high efficiency, it will save a lot of energy for the whole hotel.
Typically, the cost of electricity for an air conditioning system accounts for about 50% of the electricity cost in a building. The remaining parts are lighting, elevators and household electronic devices …
Graph of energy consumption of the building.
Inverter helps saving energy for building system
The most important thing to detect energy sources that can be saved when using an inverter in an HVAC system is to understand the operation cycle of the system as well as the operation of the cooling / heating unit compared to actual demand.
Most HVAC systems designed in buildings are to keep the building cool even on the hottest days and keep the building warm even on the coldest days.
Therefore, the HVAC system only needs to work full load in the hottest or coldest days of the year.
HVAC system in a building
Other days of the year, HVAC systems often operate at a capacity lower than the design capacity.
This is a suitable condition for using the inverter (VSD) to optimize the operation of the heating / cooling unit according to the actual requirements.
Inverter will reduce the motor speed when the system does not require full load, thereby reducing power consumption on the motor.
If a building designed with an air conditioning system is always full of loads, then using wind guards (dampers) to regulate mechanical cooling needs will not save energy.
So how much energy is saved?
Typically, a fan or centrifugal pump when working at a speed of 80% of the rated speed consumes only 50% of the rated energy level.
The diagram below describes the relationship between the flow and consumption power of a centrifugal pump:
The diagram describes the relationship between the flow and power consumption of a centrifugal pump
Devices in the HVAC system can use inverters to save energy
+ AHU fan
+ Suction fan
+ Chiller water pump
+ Hot water pump
+ Water pump for cooling tower
+ Cooling tower fan
Description of how Inverter is used in buildings
Consider the following example:
A 37kW fan works 10 hours for 250 days. Cost of electricity for fans if operating at full speed: 37kW x 2500h x 0.08 $ / kWh = 7400 $
Assuming the fan does not need to run full load during the working term:
+ 25% running time at 100% rated speed
+ 50% of the running time at 80% of the rated speed
+ 25% of the running time at 60% of the rated speed
The total energy cost for fans when controlled by inverter is as follows:
37kW x (1.00)3 x 625 x 0.08$/kWh = 1850$
37kW x (0.80)3 x 1250 x 0.08$/kWh = 1900$
37kW x (0.60)3 x 625 x 0.08$/kWh = 400$
Total = 4150$
Energy costs can be saved: 7400$ – 4150$ = 3250$
Inverter helps bring economic value
The payback period when investing in inverter is about 18-24 months on average, sometimes less than 12 months. The payback period is long or short depending on the size of the system and the rate of full load time on the total operating time.
The lifespan of equipment in HVAC systems in buildings is usually 15-20 years, so the cost of retractable inverter equipment in the span of one to two years will significantly reduce the cost of investment for later operation.
Fuji Electric’s inverter series used exclusively for HVAC applications
Frenic-eHVAC Inverter – Fuji Electric
As an inverter series exclusively for HVAC applications, it has been upgraded and upgraded from the Frenic HVAC series with outstanding features:
+ Saving more energy
+ Built-in optional EMC noise filter C2 / C3, suitable for many operating environments
+ Equipped with customized logic programming up to 200 steps.
+ Multifunctional keyboard (keypad) supports up to 19 languages, user friendly worldwide.
+ IP20, IP00 standard
+ Support multiple communication ports
+ Standard support: RS485, Modbus RTU, BACnet MS/TP
+ Support options: Profibus DP, DeviceNet, Lonworks, CC-Link
Especially: The price is 30% more economical than the previous product.
Inverter solutions for elevators
In addition to the HVAC system, elevators are used in most hotels and buildings.
Another line of Fuji Electric products can be used in all elevator systems controlled by asynchronous motors or synchronous motors.
In particular, the specialized functions for elevator applications are integrated in this inverter line, allowing elevator control, operating in the most optimal way, bringing comfort and safety to users. use.
Frenic-Lift Inverter – specialized for elevators
Please contact Hotline: 1800 6547 for more details
