Recent reports rolling out of California might leave the average person believing that digesters on animal facilities are on their way out. First, there is the battle over which is more damaging to air quality – the natural emissions from anaerobic digestion in lagoons or the emissions from the generators that turn methane into power.

I, like many others, have sat back and scratched my head, wondering how what is considered by some to be a ‘best management practice’ to manure handling can quickly become an even worse-case scenario for the environment. How can a renewable “green” energy be worse than other forms of energy?

The second reason for the dilemma over digesters revolves around no more dairy manure being delivered to the digesters at the Inland Empire Utility District in Chino, California. It appears that politics, economics and technical issues are to blame for the downfall of the project. The digesters in and of themselves worked, but the cost associated with hauling to a central site, along with irregularity of methane production, has brought the project to a rapid halt.

While many people might look at these ongoing issues and think digesters are not for agriculture, there are examples of success that continue to come. Piping methane to a central site for processing is gaining momentum (see the ‘New Technologies’ article on page 8 of this issue for more information). Also, recent indications from the current administration in Washington are bringing the avenue of carbon credits to farmers closer to reality for many operations that might be able to capture methane and other greenhouse gases.

The problem isn’t the idea or even the function of digesters. The problem is finding the best way to utilize their abilities to help producers work with their effluent stream while abiding by toughening environmental standards. There are opportunities to utilize this technology, it is just finding where those best fall in the practice of animal husbandry.


As I was reminded at the Midwest Manure Summit in Green Bay, Wisconsin, a couple of weeks ago, there are no silver bullets to handling manure. Even in Europe, where digesters are found on many production facilities, they have found that energy production from these units aren’t playing as big a picture in providing electricity as they had originally envisioned. They are, however, still considered an important part of the overall picture of manure handling and used throughout the area.

As opportunities continue to come up and regulations continue to change regarding animal production, digesters and other technologies will continue to improve and allow producers options for both improving their manure handling and helping the environment and landscape around them. While the short-term problems will continue to come into play, the long-term solutions should continue to be the focus of everyone working on manure handling and management. After all, it is usually the tougher problems that bring about the greater progress in any aspect of life. ANM

Darren Olsen
Editor for Ag Nutrient Management