Individual ROI calculations from AERZEN

Energy-efficient blower technology pays for itself after just one year

13/02/2023

The energy-saving potential of wastewater treatment plants is often underestimated. With individual ROI calculations, AERZEN illustrates the considerable cost benefits of highly efficient blower technology in the biological treatment stage and shows what short payback periods can be achieved. Thus in many cases, a more efficient design of the ventilation technology already pays for itself after twelve months.

Wastewater treatment plants have a high energy demand. 60 to 80 percent of the total electrical energy consumed is used for ventilation of the aeration tank. A switch to state-of-the-art blower technologies with the highest possible energy efficiency as well as smart, demand-oriented control and regulation technology therefore offers great leverage for reducing the total cost of ownership. At the same time, by investing in resource-saving technology, wastewater treatment plant operators are making an active contribution to greater environmental protection and a significant reduction in CO2 emissions. But how high is the savings potential really and when do the additional costs of the investment pay off? Individual ROI calculations (Return on Investment)from AERZEN provide information.

High savings, short payback times

Many wastewater treatment plant operators still focus primarily on the acquisition costs of the blowers. But the purchase price accounts for only five per cent of the total operating costs. The costs for energy, service and maintenance are much more important. Above all, it is worthwhile to look at energy consumption, because at 90 %, this is the main cost factor. With individual ROI calculations, AERZEN illustrates the considerable cost benefits of highly efficient blower technology and shows what short payback periods can be achieved. For example, by changing from a conventional Delta Blower GM 35S positive displacement blower with a motor rating of 55 kW to an innovative Delta Hybrid D 30S rotary lobe compressor with a motor rating of 37 kW, around 25 % energy can be saved (volume flow: 24 m3/min, differential pressure: 800 mbar). At an electricity price of 0.30 euros/kWh, the investment pays for itself after just one year.

Technology concept Performance3: Handle load changes precisely

For over 150 years, AERZEN has been supporting operators of wastewater treatment plants with customised solutions and has long been considered the market leader in the field of water treatment. With the efficiency concept Performance³, AERZEN offers a unique strategy for the exact control of the load changes and thus an optimal solution for an energy-efficient oxygen supply. Here, the Delta Blower positive displacement blowers, the Delta Hybrid Rotary lobe compressor and the Aerzen Turbo blowers are used in the range of their respective technological strengths and, depending on the system configuration and load, are switched in combination or as individual solutions in such a way as to achieve the most efficient solution for ventilation. Energy savings of up to 30% are possible.