Author: Robert Walton@TeamWetDog PUBLISHED May 9, 2018

The Butler pig farm includes a range of clean energy technologies, and the state’s cooperatives see its grid integration efforts as a model that can be replicated.

According to the United Nations, by 2050, the world’s food production will need to increase 70% to feed a steadily-growing population. That means more farming, and more energy demand to support it.

The International Renewable Energy Agency estimates almost a third of the world’s energy is used by the agri-food supply chain. And increasingly, many types of farms, from rice to livestock, are tapping new energy technologies to reduce their carbon footprint and maintain reliability —particularly in areas where the energy supply may be less reliable.

It’s not unusual to see a farmer utilizing wind or solar to reduce their energy needs, and at times the energy production can be more valuable than crops. But a growing number of agricultural businesses are going further, embracing grid edge technologies whole hog, if you will. And the fuel mix is often tied to the farm’s primary business.

Agricultural microgrids

“There are microgrids in the agricultural sector,” Peter Asmus, associate director at Navigant, told Utility Dive. “Using agricultural waste, I think that is something we’ll see more of. … It’s definitely a segment within the market.”

In the United States, perhaps the best known agricultural microgrid is Stone Edge Farm in Sonoma, Calif. Along with Bordeaux-style wines, they also produce olives, eggs, herbs and almost a megawatt of energy to fuel operations. The farm’s microgrid is extensive, essentially a laboratory for grid edge ideas: it utilizes a half-dozen storage technologies, and during the California wildfires was able to island itself for more than a week.

Colorado-based Husk Power Systems developed systems in India to generate electricity from gasified rice husks that are often discarded by farmers, to power local communities. On the island of Hawaii, the North Kohala Microgrid Project uses wind to power water pumping, a frequent need of farmers, for a range of local agricultural operations.

And just last week, in North Carolina, a microgrid was commissioned at the Butler Quality Pork and Renewable Energy Farm in Harnett County, and connected to the South River Electric Membership Corporation (SREMC). The system, which is member-owned and controlled, integrates renewable biogas from swine waste, solar generation and energy storage, and can power 28 nearby homes for up to four hours at peak demand.

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The Butler microgrid is unique in many ways: it was privately built by a conservation-minded local farmer, and then later connected to the cooperative’s grid. It remains under control of the farm, though in a later phase of development it will be transferred to SREMC.