Although it's not a new technology, cogeneration — or the simultaneous production of heat and electricity — is now becoming a topic of keen interest in the Florida agribusiness community.
That's because certain types of enterprises, such as phosphate fertilizer manufacturers, sugar producers and dairy farmers, enjoy unique opportunities to generate their own electricity and save a lot of money because they can produce it less expensively than they can buy it from a public utility.
For example, CF Industries Inc. in Hillsborough County and The Mosaic Company in Polk County have been using cogeneration since the 1980s to generate up to 100 percent of the electricity required for their fertilizer plants. They use as fuel the steam created as a natural byproduct of their manufacture of sulfuric acid.
CF Industries has been able to generate 100 percent of the electricity, or about 38 megawatts, required for its 24-hour-a-day, 365-day-a-year operations and offset current electrical costs of about $1.5 million per month.
For much of the year, the Mosaic plant generates more electricity than it actually needs and sells the extra power to its local utility.
At other times, when individual production lines are down for maintenance, for example, Mosaic and CF Industries supplement their self-generated power with purchases from their local utilities. CF Industries typically zeros out the balance over time, while Mosaic is a net annual exporter of electricity.
For both companies, as well as all other Florida phosphate fertilizer producers, the cogeneration of electrical power is integral to their cost structure and profitability.
Another benefit: enhanced reliability and reduced risk of a power outage.
"That is probably the most critical benefit, that assurance that we are self-reliant when it comes to our power needs," said Stefan Katzaras, CF Industries' senior community affairs specialist.
Added Brett Belknap, superintendent of the cogeneration facility: "If anything went wrong with a traditional power supplier, we could be down for 24 hours or even longer. And that would interrupt our production ability."
In addition, both CF Industries and Mosaic have been able to create power without any fossil fuel combustion or carbon emissions.
"Cogeneration has made economic sense for us since 1989," Katzaras said. "But public sentiment in the last few years has also moved in the direction of less use of fossil fuels and more focus on renewable energy."
That, he noted, translates to being seen as an environmentally responsible company.
Florida Crystals Corp., a major sugar producer, has been using cogeneration to produce electricity at its Palm Beach County plant since 1996.
That facility, which ranks as the largest biomass-to-electricity facility in North America, uses excess steam from its manufacturing process to create enough electricity to operate the company's local sugar mill during the six-month sugarcane harvest and milling season and its refinery year-round.
It also generates enough excess electricity to power about 55,000 local homes.
In effect, that means that CF Industries, Mosaic and Florida Crystals can generate cheap electricity by avoiding any costs for fuel, such as coal or natural gas, as part of the process.
In the future, it's possible that large berry producers could also use biomass from their operations to cogenerate power, according to Judi Whitson, executive director of the Hillsborough County Farm Bureau.
However, Whitson said, the most likely near-term candidates for cogeneration are big dairy farms.
Dale McClellan, owner-operator of M&B Products facilities in Hillsborough and Citrus counties, has been trying since 2004 to land $1.5 million in public or private sector grants that would allow him to capture and use the methane that is a natural byproduct of his business to cogenerate a significant portion of the electricity required to run his Citrus County farm.
The farm milks an average of just less than 700 cattle each day and pays between $120,000 and $150,000 a year for electricity from Withlacoochee River Electric Cooperative. The grant money would be used to develop the capabilities for capturing methane from wastewater and using the gas to power the turbine that generates electricity.
Without a grant, McClellan said, the capital investment required to create the capability would not make sense.
Although he has recently been discouraged by his lack of success so far, he said he now sees some progress toward having government officials and electric utilities embrace the opportunity for cogeneration.
Florida Crystals Corp. is encouraged that Florida's commissioner of agriculture, Adam Putnam, is championing biomass cogeneration.
"He's doing a phenomenal job to make the Legislature understand the importance of using agricultural waste for the reliable production of electricity," said company spokesperson Gaston Cantens.