Principles of Diesel Generator Room Layout and Benefits of Rational Design

I. Key Points for Diesel Generator Room Design

1. Layout Principles

• Safety First: This is the most fundamental and important principle, covering fire prevention, explosion prevention, electric shock prevention, exhaust gas poisoning prevention, noise hazard prevention, and other aspects.
• Ease of Operation and Maintenance: The equipment layout should reserve sufficient space for operation, maintenance, and inspection—especially around the unit, at the radiator end, and in front of the power distribution panel. Consider the transportation channel for large equipment; if necessary, reserve hoisting holes or install bridges.
• Optimized Operating Environment: The focus is on ventilation, heat dissipation, and temperature reduction. Good ventilation is key to ensuring the rated output and service life of the unit. Avoid air short-circuiting to ensure that fresh air can fully enter and hot air can be smoothly discharged.
• Minimizing Environmental Impact: Control external noise through effective sound insulation and silencing measures; reduce exhaust pollution through high-altitude emission and potential exhaust gas purification treatments.

2. Practical Tips for Equipment Selection and Capacity Control

• Unit Selection: Prioritize products with small overall size, light weight, and few auxiliary equipment. Pay attention to the room height and the channels for installation, maintenance, and transportation. Generally, air-cooled units can be selected. It is also necessary to consider the impact of the unit's installation environment, climate, altitude, and other factors on its capacity, and take appropriate correction coefficients according to the product technical specifications.
• Ways to Reduce Diesel Generator Capacity: Optimize load demand through consultation with relevant disciplines. For example, negotiate with the fire protection discipline to minimize the motor capacity of fire pumps while meeting fire water demand; adopt step-down starting for large-power asynchronous motors; adjust the starting sequence as much as possible—start large-capacity equipment first, then start small-capacity equipment in sequence, and finally connect other loads with no impact.

3. Multi-Disciplinary Collaboration and Considerations

• The design and layout of a diesel generator room require close cooperation among multiple disciplines, including architecture, structure, electrical engineering, HVAC (heating, ventilation, and air conditioning), water supply and drainage, and power. Electrical engineers put forward requirements, and other disciplines complete their respective design tasks accordingly.
• All designs must comply with the latest national and local standards and specifications. This article is based on the collation of existing search results, but standards may be updated—be sure to check the latest version.
• Specific projects may have their own particularities and additional requirements. During design, apply standards flexibly and conduct full communication and confirmation with relevant authorities (such as fire protection, environmental protection, and power supply departments).

Table 1: Core Design Dimensions and Key Points of Diesel Generator Rooms

II. Benefits of Rational Diesel Generator Room Layout

1. Enhanced Safety and Reliability

• Personnel Safety Guarantee: Strict fire separation (fire walls, fire doors), reliable exhaust gas emission systems (preventing carbon monoxide accumulation), and effective noise prevention measures jointly ensure the personal safety of operation and maintenance personnel and nearby residents, avoiding occupational risks such as poisoning and hearing damage.
• Equipment Safety Guarantee: A good layout provides a suitable operating environment for equipment. Sufficient air intake and exhaust prevent the generator from load reduction or shutdown due to overheating; reasonable spacing avoids overcrowding of equipment, facilitating daily inspection and maintenance and timely detection of potential problems.
• Emergency Power Supply Reliability: When the municipal power supply is interrupted, a reasonably designed room ensures that the generator starts quickly, switches seamlessly, and continuously supplies power to critical loads (such as fire elevators, emergency lighting, data center servers, etc.) until the municipal power supply is restored. This is the ultimate goal of the entire emergency power supply system.

2. Optimized Operational Efficiency and Economy

• Improved Power Generation Efficiency: Diesel generators achieve the highest efficiency at rated operating temperatures. Excellent ventilation and heat dissipation design can effectively control the room temperature within the ideal range, avoiding efficiency reduction and insufficient output power of the unit due to overheating, thereby saving fuel consumption.
• Reduced Fuel Costs: Improved efficiency directly means less diesel is needed to generate the same amount of electricity, which is a considerable saving in the long run.
• Lower Maintenance Costs: A clean, dry, and well-ventilated environment reduces the erosion of dust and moisture on the engine, control system, and radiator, extending equipment service life and reducing failure rates and the frequency of parts replacement.
• Avoidance of Fines and Rectification Costs: Compliance with environmental protection (noise, exhaust gas) and fire protection standards avoids penalties and expensive later transformation costs due to violations.

3. Ease of Operation and Maintenance

• Sufficient Operation Space: Reserve sufficient maintenance channels around the equipment, in front of the power distribution panel, and at the radiator end, facilitating daily operations, instrument reading, fault diagnosis, and maintenance work, and improving work efficiency.
• Convenient Equipment Replacement: Consider equipment transportation channels (such as hoisting holes, sufficiently wide doors), making it possible to replace large components (such as engines, generator bodies) or the entire unit in the future without large-scale destructive transformation of the building.
• Simplified Inspection Routes: Clear channels and reasonable equipment arrangement make daily inspection routes shorter and smoother, with no dead ends, making it easy to detect problems such as leakage.

4. Compliance with Environmental Protection and Regulatory Requirements

• Noise Control: Through sound insulation and silencing measures, control the operating noise and exhaust noise of the unit within the limits required by environmental protection regulations, avoiding disturbance to the surrounding environment (such as office buildings, hospitals, residential areas).
• Compliant Exhaust Emission: Design the exhaust pipe reasonably to ensure high-altitude emission and sufficient diffusion of exhaust gas; cooperate with necessary treatment devices to meet air pollutant emission standards.
• Pollution Prevention: Anti-leakage design and drainage/oil discharge measures in the oil storage room effectively prevent soil and groundwater pollution caused by diesel leakage.

5. Maximized Space Utilization and Overall Coordination

• Compact and Efficient: On the premise of meeting all safety spacing and operation requirements, minimize the total area required by the room through refined design, freeing up valuable space for other functional areas.
• Seamless Integration with the Building: Rational site selection and layout (such as the location of air inlets, air outlets, and exhaust ports) can better integrate with the building's facade and internal circulation, reducing negative impacts on the building's appearance and functional layout.

Table 2: Comparison Between Rational and Irrational Diesel Generator Room Layout

III. Basic Installation Content of Diesel Generator Rooms

1. Foundation and Installation

• Anti-Vibration Devices: For Cummins series diesel generator sets, high-efficiency anti-vibration devices are pre-installed, which can eliminate approximately 85-90% of the unit's vibration. At the same time, the unit is equipped with bellows for exhaust system installation when leaving the factory, which are used to isolate the unit's vibration from the exhaust system. During installation, users should take necessary anti-vibration measures simultaneously, such as using flexible connections for output cable connections, adopting elastic bell mouth air guide grooves for air outlets, and elastic hoisting for the exhaust system.
• Foundation Requirements: Cummins series units have excellent anti-vibration performance, so no specific foundation is required for the generator set. The unit can be directly installed on a horizontal and sufficiently strong concrete floor. The floor should be horizontal and flat (flatness requirement within a 0.5° plane) and must be able to bear 1.5-2 times the static weight of the generator set.
• Foundation Size Calculation: If the floor in the room cannot meet the load-bearing requirements, a concrete foundation can be used for installation. This is a simple, reliable, and low-cost installation method. The specific method is shown in Figure 1 and Figure 2. The thickness of the machine base can be designed and calculated according to the following formula:
  FD = W/(D×B×L) —— (Formula 1)
  • FD: Thickness of the machine base (m)
  • W: Total wet weight of the generator set (Kg)
  • D: Concrete density (2403 Kg/m³)
  • B: Width of the machine base (m)
  • L: Length of the machine base (m)

The concrete foundation should usually be 100-200mm higher than the ordinary floor to form a base. When pouring the concrete foundation platform, ensure that the concrete foundation is horizontal and that the foundation platform has sufficient capacity to bear the generator set.

• The diesel generator room must have sufficient space to allow free air circulation, which is very important for ensuring the normal performance of the unit, reducing the power loss of the unit, and ensuring the normal service life of the unit. No other flammable and explosive materials, or objects that may be drawn into the unit's protective net or directly sucked into the unit body and affect the normal use of the unit, should be placed inside the room.
• For the installation of units without special requirements, the design requirements for the room are not high. It only needs to ensure that the air inlets and outlets of the room meet the technical specifications (on the premise that the exhaust back pressure does not exceed the specified value), avoid hot air backflow, and reserve sufficient operation and maintenance space inside the room.
• For some rooms that need to make and place backup fuel tanks inside, attention should be paid to isolating them from the main space of the room and meeting the requirements of local environmental protection and fire protection departments.
• The room should be equipped with sufficient air inlets and outlets. If the cooling capacity of air intake and exhaust is insufficient, an additional exhaust duct should be installed or a remote water tank installation method should be adopted. When selecting the specific placement position of the diesel generator set in the room, priority should be given to reserving sufficient operation and maintenance space and air circulation space around and above the unit.
• When supporting facilities such as an automatic transfer switch (ATS) system or a synchronous parallel operation system are installed in the room, sufficient operation and maintenance space should be reserved around the equipment.

Conclusion