SAP Conversion Models: Brownfield, Greenfield, and Shell Conversion

Migrating to SAP S/4HANA is a complex and challenging process, as it involves transferring data and processes from an existing platform to a new one. Choosing the right SAP conversion model is crucial for project success, as it will directly impact the time, cost, and risks involved.

There are three main SAP conversion models:

• Brownfield: The brownfield strategy involves migrating data to a new platform using existing infrastructure. This is the fastest and least expensive strategy, but it can also be the most complex.
  
• Greenfield: The greenfield strategy involves creating a new SAP S/4HANA implementation from scratch. This is the slowest and most expensive strategy, but it can also be the simplest.
  
• Shell conversion: The shell conversion strategy involves creating a new S/4HANA system while retaining existing transactional data from the SAP ECC system. This is a hybrid strategy that can be a good option for companies that need to migrate quickly but also want to leverage the benefits of S/4HANA.

Challenges in selecting an SAP migration strategy

Selecting the conversion model can be challenging, as there are many factors to consider. Some of the main challenges include:

• The size and complexity of your data: Data is one of a company's most important assets. It's important to consider the size and complexity of your data when choosing a migration strategy.
  
• Performance and availability requirements: SAP S/4HANA is a next-generation platform offering advanced features. It's important to consider your performance and availability requirements when choosing a migration strategy.
  
• Your budget: Migrating to SAP S/4HANA can be an expensive process. It's important to consider your budget when choosing a migration strategy.
  
• Your experience with data migration: Migrating to SAP S/4HANA can be a complex process. It's important to consider your data migration experience when choosing a migration strategy.

Advantages and disadvantages of each SAP conversion model

Brownfield Strategy - Legacy system conversion

The best approach for companies that want to leverage existing solutions, preserve historical data, and quickly convert to S/4HANA, then gradually adopt the innovations enabled by SAP.

With this approach, we load all configurations, customizations, and transactional data—meaning the entire history—and migrate them to the new environment.

Brownfield Advantages:

• Faster
• More cost-effective
• Easier to integrate with existing systems

Brownfield Disadvantages:

• More complex
• Requires more testing and validation
• Can be difficult to scale

Greenfield Strategy - New system implementation

During the implementation of this method, all processes and systems are completely reinstalled and configured. All existing systems will be reviewed and, if necessary, replaced throughout this process.

Greenfield Advantages:

• Simpler
• Easier to manage
• Scalable

Greenfield Disadvantages:

• Slower and more expensive
• Higher risks
• More difficult to integrate with existing systems

Shell Conversion Strategy - Migrating from legacy to new system

It's a combination of the Greenfield and Brownfield approaches; it leverages the value of the existing solution while offering greater flexibility in defining the execution phase, allowing for separate executions for different business codes and optimizing system downtime.

Shell Conversion Advantages:

• Combines the benefits of brownfield and greenfield strategies
• Faster than the greenfield strategy
• Allows companies to leverage S/4HANA benefits more quickly
  

Shell Conversion Disadvantages:

• Requires maintaining two systems simultaneously
• Can be more expensive than the brownfield strategy

When each strategy is recommended

The best migration strategy for your company will depend on your specific needs. Generally, the brownfield strategy is recommended for companies that need to migrate quickly and have a limited budget. The greenfield strategy is recommended for companies that want to fully leverage the benefits of S/4HANA and have a more flexible budget. The shell conversion strategy is a good option for companies that need to migrate quickly but also want to take advantage of S/4HANA's benefits.

Choosing the right SAP conversion models is crucial for the success of your SAP S/4HANA migration project. It's important to consider all factors involved, including the size and complexity of your data, performance and availability requirements, your budget, and your experience with data migration.

See also: 1st S/4HANA Market Research in Brazil

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