Martine Stillman, Mechanical Engineering Program Lead at Synapse, was qu
Farmers today face a significant operational challenge that adversely impacts their bottom line - they don’t have good data regarding the amount of nitrogen in their soil, which prevents them from optimizing fertilizer application to maximize yield. A common strategy to address this issue is to apply more nitrogen than needed to ensure acceptable yield, but this practice is expensive and often results in groundwater contamination. The cost of nitrogen overapplication in the United States is significant and some sources estimate that fertilizer is typically applied at levels 20% higher than necessary.
Soil Analysis Today
The best soil analysis technology available to farmers today requires manually drilling for core samples throughout their fields. After mixing samples together, the soil is sent to a lab for analysis. This sampling process is costly, labor-intensive, time-consuming, and is typically too coarse of a measurement, due to field soil variation becoming lost with sample mixing. These current nitrogen sampling methods are sub-optimal, and on top of everything else, can take several weeks to get results.
Our team of engineers at Synapse and Cambridge Consultants developed concepts for a commercially viable soil sample retrieval and analysis system, improving sampling speed, resolution, and ease of use. We looked at the current state of the sample retrieval problem and explored the existing solutions for farmers today. After several ideation sessions, we evaluated concepts against a set of evaluation criteria and chose to develop a solution around the subsoiler sampling method, which is expected to be the most effective at meeting speed, cost, depth, and robustness targets. This system continuously transports soil to the on-board analysis system via an extractor near the rear of the subsoiler blade.
Finally, we developed an economic model to determine the potential cost savings from optimizing nitrogen inputs in the corn farming process. By using this more advanced sampling method, the average Iowa corn farm could save $4,000 to $12,500 annually, depending on nitrogen prices and other input variables. Across the entire United States, this would result in potential savings of up to $2.5 billion.