ArcelorMittal Steel USA is finding an uncommon way to beat the competition: It is cutting energy consumption at one of its steel plants in Chicago by re-using heat to make electricity. It says that it is saving $100 million a year by creating an extra 75 megawatts of emissions-free electricity.
It’s not just steel manufacturers that are able to use such combined heat and power technologies. It’s also oil and gas processing businesses, as well as iron, chemical and cement makers. Scientists are saying that the recycling of wasted energy is a productive tool that both improves energy efficiency and minimizes the release of greenhouse emissions.
“Increasing America’s industrial energy efficiency can produce more power from natural gas, coal, landfill gas, and biomass with less waste. There are benefits for the consumer, businesses, and the environment. It also means reducing the pressure on our commercial electricity grid making it more reliable. Getting more energy from the same amount of fuel also helps communities avoid the need to build new power plants at an additional cost to ratepayers,” writes Tracy Schario, with the Pew Charitable Trust.
Consider that for every BTU of coal or natural gas burned in a combustion turbine only 35 percent of that is converted into useful power. The other 65 percent is lost forever in the form of waste heat discharged into the environment. Interestingly, the technology exists to modify that waste heat — a tool that could gain ever-increasing credence if natural gas and coal prices turn volatile.
Increasing industrial energy efficiencies could generate $200 billion in new private investment in the United States, according to the Oak Ridge National Laboratory. Altogether, it is saying that the expansion of co-generation could provide 20 percent of the nation’s generation capacity by 2020.
The White House, in fact, is adding that the combined heat and power systems could save manufacturers as much as $100 billion a year. That would come from reducing energy costs, improving bottom lines and bolstering their competitive positions. To that end, President Obama signed an executive order in August that calls for increasing combined heat and power by 50 percent by 2020. That equates to 40,000 megawatts of electricity, or enough to displace 80 large coal plants.
“This action will cut costs, increase efficiency, and help our businesses create strong, middle class jobs,” says President Obama. “We’ll continue to do everything we can to put more people back to work and build an economy that lasts.”
Recycling energy falls under the category of combined heat and power, which generates and uses both electricity and thermal heat-a technology that is now eligible to receive 10 percent investment tax credits from the U.S. government. Those kind of units produce about 12 percent of all electricity in this country.
Because the recycling process requires no added fuels, there’s a huge window of opportunity to capture energy in those refineries and industries where the wasted heat is released at 300-700 degrees Fahrenheit. Put simply, it is like boiling water and then using the steam to power other things in the house. But for all practical purposes, the steam is just released and lost forever.
This is a practice popular among European industrials with many of them producing as much as 20 percent of their power this way.
But there are some regulatory barriers to overcome before those systems could be functional here. The New Source Review provision under the Clean Air Act, for example, is intended to prevent older coal-fired power plants from equipping their old units to produce more energy that release more pollutants.
Some power operators fear, however, that that they will get sued if they equip their facilities so that they could capture excess heat, which could alter the generation process and thus violate the New Source Review, writes Melissa Mullarkey, for Recycled Energy Development. The problem remains, though, that while the technology is able to cut carbon dioxide emissions, it may still increase another one: nitrogen oxide, tied to smog and acid rain.
Furthermore, cost is a deterrent. Central generation has been reported to be notably less expensive per kilowatt than that of local generation, which is at the core of the recycling process. However, with a big plant, there’s a need for transmission and distribution — all of which adds to the expense of building a central power facility and which makes onsite power more attractive.
Energy is wasted daily. And a marketplace void now exists to recapture waste heat and to apply it to create electricity. Proponents of the concept say that the technology is available today to do just that but that high costs and regulatory impediments stand in the way. Participation by the White House is a start, they say, and one that will lead to fewer power plants and much cleaner air.