450kW gas cogenerator achieves 81.5% overall efficiency

Generating efficiency is 42.0%, which MHI says is the world's highest level in the 400kW class. Overall efficiency is a robust 81.5% for the hot water type (SGP M450-W), which uses all recovered heat for hot water. The overall efficiency of the hot water and steam supply type (SGP M450-S) is 80.5%.

In addition to these achievements in power output and generating efficiency, increased merits in terms of both initial costs and running costs were pursued through the elimination of the need for denitrification equipment. Together, these benefits enable a faster investment return than with the 380kW system. A 20% reduction in installation space requirements has also been achieved by trimming the physical dimensions of the main unit.

In the wake of the Great East Japan Earthquake of 2011, customer interest in gas cogeneration systems has strengthened, not only due to their efficient energy use, but also for their contributions to achieving power security and saving power in line with business continuity plans. Customers are also showing greater interest in achieving higher performance levels.

Going forward, MHI and Toho Gas intend to propose the 450kW gas cogeneration system for adoption in hospitals, commercial facilities, office buildings and factories, as a way of promoting the further adoption of these efficient systems, while simultaneously making positive contributions to saving energy and easing burdens on the environment.

The 450kW gas engine achieves near 20% higher output and the highest level of generating efficiency in its class: 42.0% - made possible largely through optimised combustion as well as the adoption of a water-cooled turbocharger and high-efficiency generator. In addition the intercooler, which cools the fuel-air mixture and raises air density, has been upgraded from the earlier one-stage type to a two-stage configuration. By recovering heat from the first stage, the two-stage intercooler has increased overall efficiency to 81.5%.

By simultaneously achieving higher efficiency, increased output and low nitrogen oxide emissions, enabling elimination of denitrification equipment, the gas cogeneration system reduces initial costs and increases running cost merits. As a result, the customer stands to benefit from a quicker return on system investment.

Thanks to the adoption of a new package layout and optimal equipment layout, installation space needs have been trimmed by 20%.