For decades, governments and regulatory bodies have been strategising how to monitor emission output and find new ways to improve overall air quality with the aim to transition into more eco-friendly, affordable and reliable power solutions. To achieve this, international governments put in place a tier rating system for all off-road engines designed to power up equipment, items, machinery and site operations.

Here, we’ll explain what a diesel generator tier rating is and how these tiers have changed emission restrictions.

What is a Diesel Generator Tier Rating?

When a generator is in operation, it will emit carbon particles such as Sulfur, Nitrogen Oxide (NOx), non-methane hydrocarbons (NMHC) and Particulate Matter (PM) into the atmosphere. To combat this, a generator tier rating system was established in the early 1990s to monitor and eventually place restrictions on the amount of emission output a diesel generator can produce.

Eventually, these tier ratings were to move towards more efficient, greener engines to improve overall air quality. As a result, countries began placing restrictions on emission output of engines designed for construction, mining and other diesel-driven equipment and operations. 

What Are the Generator Tiers? 

The implementation of generator tiers began overseas in Europe and the United States to place regulatory restrictions of harmful emission output. The regulations of exhaust emissions gradually increased over time to allow for manufacturers to adapt to new technologies that could make this happen.

As a result, each tier (or phase) was allocated within a rating system to correlate to an engine’s horsepower (hp). Over time, these tier regulations have only become stricter. They are known as:

• Tier I
• Tier II
• Tier III
• Tier IV 

Tier 1:

The first standards of diesel engines were published in 1991, however its implementation did not occur until 1996. It allowed governments to set emission standards for manufactures to ensure all off-road diesel engine power sources were compliant.

These standards primarily focussed on diesel engines under 37 kW (50 hp) and were phased out between 1996 - 2000.

Tier 2:

The next phase of standards came into place from 2000-2005, enforcing further restrictions on NOx, NMHC and PM emission outputs as well as the amount of Sulphur was allowed in diesel fuel. It wasn’t until 2001, however, until Tier 2 engines were being implemented.

In order to meet the criteria of Tier 2 regulations, the technologies used to build these generators allowed engine designs to become more refined with better overall performance.

Tier 3:

Tier 3 regulations came out shortly after Tier 2 from 2006-2008. Eventually placing further restrictions on emission output for diesel engines powering 50 - 750 horsepower (hp).

Tier 4:

Tier 4 regulations are the strictest regulations to date, requiring the most modern technologies to reduce the output of PM, NMHC and NOx by 90%. They were phased in from 2008 - 2015.

What are the Benefits of Tier 4 Generators? 

In addition to improving air quality, Tier 4 generator benefits also include:

• Significant reduction of overall emission output
• Often a smoother and quieter operation
• Better fuel efficiency
• Lower operational costs
   

What Applications Require Tier 4 Standards? 

There are many generators that currently need to adhere to Tier 4 standards, here are some of the most common:

Prime Power Generators 

As the name hints, prime power generators are designed for providing the primary source of power for those who are either disconnected or do not have access to the grid. It will operate continuously, providing stable power for any equipment, machinery, utilities and other items. Due to the run-time of prime power generators are subjected to, they must comply with Tier 4 regulations.

If you’re in need of a stable, prime power source, check out our range of prime power generators here.

Portable Generators 

Particularly when used for commercial, construction or industrial applications, portable generators must also operate under Tier 4 regulations. Especially in cases where construction sites, projects or events are operating off the main grid.

What About Emergency Generator Ratings? 

Emergency and back-up generators operate under slightly different regulations than prime and continuous power generators. While these are regulated to meet Tier 4 standards, emergency generators are subject to Tier 2 or Tier 3 standards. This is because they are only required to operate temporarily, and therefore, have less of impact on overall air quality.

Need a Power Solution? Get Expert Advice.

With years of experience servicing the mining, construction industries, Blue Diamond Machinery has the equipment you need and can rely on. We not only offer expert advice and industry-leading warranties, we provide an all-encompassing solution. We will customise and install your power solution to your specific power demand requirements, wherever you are. Get in touch with our team today.