Diesel generator sets are widely used as backup power sources in offices, factories, hospitals, commercial buildings, construction sites, and other facilities. While DG sets provide reliable electricity, their engines also produce exhaust emissions such as particulate matter, carbon monoxide, hydrocarbons, and nitrogen oxides.

As environmental requirements become more important, emission control solutions are increasingly used with existing diesel generators. One such solution is a RECD for DG set, which is designed to help control emissions from an existing diesel generator without replacing the complete generator.

But what exactly is RECD, how does it work, and when is it useful? This guide explains the basics in simple terms.

What Is a Retrofit Emission Control Device (RECD)?

RECD stands for Retrofit Emission Control Device. It is an emission-control system installed on an existing diesel generator to reduce certain pollutants in its exhaust.

The main idea behind a retrofit system is simple: instead of replacing an older generator with a completely new unit, an appropriate emission-control device can be integrated with the existing DG set where technically and legally applicable.

A DG set RECD device is generally installed as part of the exhaust system. Depending on the technology and configuration, it may use filtration, oxidation, catalytic treatment, or a combination of emission-control technologies.

The actual performance and suitability depend on the engine, generator specifications, emission characteristics, device design, installation, and applicable requirements.

Why Is RECD Used for Diesel Generators?

Diesel engines naturally produce exhaust gases and particulate matter during combustion. Older generators may not have the same emission-control technology found in newer equipment.

A suitable retrofit system can help address emissions from an existing generator.

Common reasons for considering RECD include:

• Improving exhaust emission control

• Supporting applicable environmental requirements

• Continuing to use an existing DG set where permitted

• Reducing the need for immediate equipment replacement

• Upgrading emission-control capability

• Supporting cleaner operation of existing generator equipment

However, RECD should not be considered a replacement for proper engine maintenance. If an engine has problems such as poor combustion, faulty injectors, excessive oil consumption, or inadequate compression, those issues should be diagnosed and repaired separately.

How Does an RECD Work?

The working principle depends on the specific technology used in the retrofit system.

In general, exhaust gases produced by the diesel engine pass through the emission-control equipment before being released through the exhaust outlet.

The system may help control pollutants through processes such as:

Filtration

Some systems use filtration technology to capture particulate matter from diesel exhaust.

Oxidation

Catalytic components can help convert certain pollutants into less harmful compounds through oxidation reactions.

Catalytic Treatment

Certain retrofit technologies use catalysts to support chemical reactions that reduce specific exhaust pollutants.

Monitoring and Control

Advanced systems may include sensors and controllers to monitor operating conditions and support proper functioning of the emission-control equipment.

The exact technology should be selected according to the DG set's engine specifications and applicable technical requirements.

What Are the Main Components of an RECD System?

An RECD installation can contain different components depending on the technology and generator configuration.

Common components may include:

• Emission-control unit

• Exhaust piping

• Filters or catalytic elements

• Sensors

• Temperature monitoring components

• Control unit

• Pressure monitoring system

• Mounting arrangements

• Electrical connections

• Exhaust insulation

Not every RECD system will contain all these components. The configuration should be determined based on the particular generator and emission-control technology.

What Are the Benefits of Using an RECD?

A properly selected and installed retrofit emission control device for generator applications can offer several practical benefits.

1. Emission Control

The primary purpose of RECD is to control specific pollutants produced by diesel engine exhaust.

2. Existing Generator Can Be Retrofitted

A retrofit approach may allow an existing DG set to receive additional emission-control equipment rather than requiring immediate replacement, subject to applicable requirements and technical suitability.

3. Supports Environmental Compliance

Where retrofit emission-control requirements apply, an appropriate system can support compliance efforts. The specific requirements should always be checked according to the generator's capacity, location, age, and applicable regulations.

4. Supports Cleaner Generator Operation

Controlling exhaust pollutants can contribute to cleaner operation and better environmental management.

5. Potentially Lower Replacement Requirement

For suitable existing generators, retrofitting may provide an alternative to replacing the complete generator. Whether it is economically beneficial depends on the condition and remaining useful life of the DG set.

Is RECD Mandatory for Every DG Set?

No. It is important not to assume that every diesel generator automatically requires the same retrofit system.

Requirements can depend on factors such as:

• Generator capacity

• Generator age

• Location

• Applicable environmental regulations

• Engine specifications

• Existing emission-control equipment

• Applicable certification or approval requirements

Therefore, generator owners should verify the requirements applicable to their particular DG set before selecting or installing a retrofit system.

What Should You Check Before Choosing an RECD?

Choosing the correct system is important because one emission-control device may not be suitable for every generator.

Before purchasing an RECD, check the following:

DG Set Capacity

Confirm the generator's kVA rating and operating conditions.

Engine Specifications

The engine model, fuel system, exhaust configuration, and emission characteristics can affect system selection.

Exhaust Configuration

The retrofit equipment must be compatible with the existing exhaust arrangement.

Applicable Requirements

Check the environmental and technical requirements applicable to your generator and location.

Installation Requirements

Consider available space, exhaust back pressure, mounting arrangements, electrical requirements, and accessibility for maintenance.

Maintenance Requirements

Understand how frequently filters, sensors, catalysts, or other components need inspection or servicing.

Why Is Proper Installation Important?

Correct installation is essential for the effective operation of an RECD for DG set.

An incorrectly installed system can create problems such as:

• Excessive exhaust back pressure

• Poor engine performance

• High exhaust temperature

• Incorrect sensor readings

• Reduced emission-control performance

• Increased maintenance requirements

The exhaust system should therefore be evaluated before installation. The retrofit equipment should be installed according to the manufacturer's technical instructions and the applicable requirements.

Does RECD Replace Generator Maintenance?

No.

RECD is an emission-control solution, not a substitute for regular DG-set maintenance.

A generator should still receive routine checks such as:

• Engine oil inspection

• Oil and fuel filter replacement

• Air filter inspection

• Coolant checks

• Battery inspection

• Fuel-system maintenance

• Injector inspection

• Exhaust-system inspection

• Alternator checks

• Control-panel checks

If the engine is producing excessive smoke because of a mechanical or fuel-system problem, the root cause should be repaired. Installing an emission-control device alone does not correct an unhealthy engine.

How Does RECD Differ From Buying a New Generator?

A new generator and a retrofit emission-control system are different solutions.

The better option depends on the generator's condition, power requirements, applicable regulations, available budget, and long-term plans.

Who Can Benefit From an RECD?

An appropriate retrofit system may be considered by organizations that operate existing diesel generators and need to improve emission control.

Potential users include:

• Manufacturing facilities

• Commercial buildings

• Hospitals

• Data centers

• Construction sites

• Educational institutions

• Residential complexes

• Warehouses

• Industrial facilities

• Offices

The suitability of RECD should be evaluated on a case-by-case basis rather than assuming that one solution fits every DG set.

Why Choose the Right RECD Supplier?

The supplier plays an important role in selecting and implementing a retrofit system.

A reliable supplier should be able to provide:

• Technical product information

• DG-set compatibility guidance

• Installation recommendations

• Relevant documentation

• Maintenance guidance

• After-sales technical support

• Assistance with system selection

ACEGET provides solutions and technical guidance for DG-set emission-control applications. Before selecting a system, generator owners should provide accurate details about their DG set so that the appropriate solution can be evaluated.

What Information Should You Give the Supplier?

When asking for an RECD solution, keep the following information ready:

• DG set manufacturer

• Generator model

• Engine model

• kVA rating

• Fuel type

• Engine age

• Exhaust pipe size

• Current emission-control equipment

• Operating hours

• Installation location

Providing accurate information helps the supplier understand the generator configuration and recommend a suitable retrofit approach.

How Can You Learn More About RECD for DG Sets?

If you are planning to retrofit an existing diesel generator, it is useful to understand the complete process before purchasing equipment.

For additional information, you can read How to Safely Dispose of an Old Diesel Generator when evaluating what to do with an older DG set that may be nearing the end of its useful life.

This can help generator owners compare options such as continued operation, refurbishment, retrofit, resale, or disposal.

Conclusion

A DG set RECD device is an emission-control solution designed to be integrated with an existing diesel generator where technically suitable and applicable requirements call for or support such a retrofit.

A properly selected retrofit emission control device for generator applications can help control certain exhaust pollutants while allowing a suitable existing DG set to continue operating. However, RECD selection should always consider the generator's capacity, engine specifications, exhaust configuration, applicable requirements, installation conditions, and maintenance needs.

Most importantly, RECD should work alongside proper generator maintenance rather than replace it. A healthy engine, correct installation, regular servicing, and an appropriate emission-control system together provide a more effective approach to responsible DG-set operation.

FAQs

What does RECD stand for?

RECD stands for Retrofit Emission Control Device. It is an emission-control system designed for installation on an existing diesel generator where applicable.

What is the purpose of an RECD?

The main purpose of an RECD is to help control specific pollutants in diesel generator exhaust.

Is RECD required for every diesel generator?

No. Requirements can vary depending on factors such as generator capacity, age, location, engine specifications, and applicable regulations.

Can RECD be installed on an old DG set?

Potentially, yes. However, technical compatibility and applicable requirements should be evaluated before installation.

Does RECD improve a damaged engine?

No. RECD is an emission-control system. Mechanical problems such as faulty injectors, poor compression, or excessive oil consumption should be diagnosed and repaired separately.

How do I choose the right RECD for my DG set?

Check the generator capacity, engine model, exhaust configuration, operating conditions, applicable requirements, installation conditions, and maintenance requirements before selecting a system.

Why is RECD installation important?

Proper installation helps ensure that the emission-control system works correctly without creating unnecessary exhaust back pressure or other operational problems.