US: California Greenhouse fertilizes tomatoes with generator exhaust

A leading grower of North American greenhouse tomatoes recently teamed up with GE to increase efficiency of its Camarillo, Calif., operation. Instead of setting up wind turbines or solar panels, Houweling’s Tomatoes greenhouse allowed GE to install the nation’s first combined heat and power (CHP) system, a process captures carbon dioxide (CO2) for use as plant fertilizer.

Using two of GE’s 4.36-megawatt (MW), ecomagination-qualified Jenbacher J624 two-staged turbocharged natural gas engines and a GE-designed CO2 fertilization system, the plant provides heat, power and CO2 to Houweling’s 125-acre tomato greenhouse. According to GE, the system enables flexible power generation and contributes outside-grid electricity during peak daytime demand periods.

The only thing that’s troublesome about this system is that the capture C02 doesn’t stay in the grid…it becomes part of the food system. CO2 from the turbines’ engine exhaust will be purified and piped into the greenhouse to fertilize the plants during the daylight photosynthesis process.

The idea of fertilizing plants with engine exhaust sounds gross, but GE claims its system, tested extensively in the Netherlands, removes almost all unwanted carbon monoxide and nitrous oxides with special catalytic reduction equipment. Also by capturing this exhaust for plant food instead of releasing it into the air, one Jenbacher J624 two-stage turbocharged gas engine saves about 10,700 tons of CO2 per year. That’s the equivalent of taking more than 2,000 U.S. cars off the road.

“The impact of this project on the region goes far beyond the vegetables produced in the greenhouse,” said Casey Houweling, owner of the greenhouse facility. ”This ultra-high-efficiency CHP plant also will provide flexible power to our local utility with a very short response time. GE’s proven technology and industry-leading efficiencies allow us to have one of the lowest C02 footprints and water usage in the region for a power plant of this size. In fact, we plan to use the water condensed out of the exhaust gas in our operations—this will save approximately 9,500 gallons per day of usage from local water sources. We felt this project was the right thing to do for both our company and our community.”