Power Generation - University Seeks Tier 4 Final Solution with Active DPF Technology - MIRATECH

Power Generation – University Seeks Tier 4 Final Solution with Active DPF Technology


In 2022, MIRATECH was approached by a California-based engineering firm to provide a Tier 4 compliant solution to pair with (3) CAT 3516C 2500kW backup diesel engines being installed at a university in California within the South Coast Air Quality Management District.


Like most projects, this project brought a few challenges. First and foremost, this end user preferred peace of mind by not worrying about bringing the engine up to 500°F for the diesel particulate filter regeneration. The second challenge was making the aftertreatment housing solution low profile to keep the backup generators and exhaust piping out of sight on campus. Lastly, like many California projects, space was limited for all the aftertreatment dosing system components and Urea tanks that are required to operate the Tier 4 system.


To combat the university’s first challenge, MIRATECH introduced them to the AT-IV. The AT-IV combines active regeneration DPF technology from RYPOS with MIRATECH’s diesel oxidation catalyst and SCR technology. The active regeneration DPF technology self-cleans by efficiently burning soot in the filter in under three minutes while using less than 1% of the generator output. The self-cleaning technology provides peace of mind, as well as reducing on-site operating maintenance of the total system. In addition, the AT-IV combines the active DPF/SCR/DOC technologies into a single steel housing, which reduces installation costs and overall space claim on site.

With the AT-IV utilizing a “top out” outlet design, this was an initial concern due to the challenge of keeping the system and exhaust piping out of sight to the campus community. The end user’s goal was to use a 90° elbow to run the exhaust piping as low in height as possible. In response, the MIRATECH engineering team adeptly designed an integrated 90° elbow from the outlet (shown below), rather than using a typical flange design. The integrated elbow reduced the height of the exhaust piping to stay below the max height allowed per the zoning requirement, which ultimately kept the exhaust run below a wall and out of sight on campus.

Lastly, to address the space constraint for required SCR components such as air compressors, dosing boxes, reactant booster pumps, urea tanks, etc., MIRATECH introduced the customer to the RTS-550, a fully integrated single controls cabinet with urea tank enclosure. The RTS-550 houses all pre-wired components in a heated and cooled stainless-steel enclosure that sits on top of a 650-gallon stainless-steel urea tank. This solution allows for an organized and pain-free installation with a considerably more compact overall site footprint.


Backup generator projects in California have increased in recent years due to the California grid power system that, many times, requires planned blackouts. This creates issues for many mission-critical buildings that require uninterrupted power supply. With the increase in generators combined with the rise in Tier 4 Final emissions regulations, many end users are seeking the most worry-free technology on the market, combined with small footprint packages that allow for ease of install and lower maintenance costs.

MIRATECH has combined its market-leading DOC and SCR systems with the RYPOS CARB-verified active regeneration DPF system in a highly flexible, single-point, turnkey product line. It will help engine users meet Tier 4 emissions compliance along with current and proposed state regulations that require greater emission reductions without the operational limitations of EPA certified engines.