Combined Heat and Power Distributed Generation Renewable Energy

Lancaster Water Reclamation Plant IR MT 250 Microturbine Digester gas fueled 225 kWe plus heat recovery 51% Electric and thermal eff. 4 ppm NOx and CO

1865 West Avenue D Lancaster, California Background In 2003, Sanitation District No. 14 entered into an agreement with Ingersoll-Rand (IR) to demonstrate their 250 kW microturbine fueled by digester gas. This program includes an IR gas conditioning system based on research by the Sanitation Districts for removal of contaminants in the gas and the culmination of over 20 years of research and development by IR on the microturbine. Water Reclamation Plant The Lancaster WRP currently provides primary and secondary treatment (aerated oxidation ponds) for up to 16 million gallons of wastewater per day. The plant has the capacity to serve a population of approximately 160,000 people. Power Generation and Heat Recovery At full power the microturbine will produce 250 kW of electricity and sufficient hot water to heat the WRP digesters. The net power output of 225 kW represents 24% of the plant demand. Approximately 64% of the available digester gas will be consumed by the microturbine. Digester gas is known to contain moisture and silica compounds that can be harmful to power generation equipment.This facility utilizes a novel gas conditioning system that reduces the gas to –20 degrees F and then reheats the gas.Pilot testing by the Sanitation Districts Research Section indicates this reduces contaminants by over 95%. IR will provide both operating and maintenance services for the first three years. The project has an automatic control system that allows review of the plant operations over the internet. The facility is designed to operate independently of the WRP. During periods when the facility is not operational, electricity is provided by the utility and an onsite boiler automatically supplies hot water to heat the digesters. Benefits The completed project will provide economical electricity and hot water to supply the plant’s energy needs with a combined electrical and thermal efficiency of up to 51%. Environmental benefits include a reduction of greenhouse emissions, air emissions that are less than the gas flares, and the reduction of air emissions associated with less consumption of utility central generating plants. By generating power where it is needed there is also a reduced need for utility transmission and distribution facilities. The Sanitation Districts funded the total installed cost of $720,000 with assistance from the California Public Utilities Commission’s Self-Generation Incentive Program. As a result of this funding, the savings in electrical purchases is expected to pay for the facility in less than 3 years.