Archive for the 'Waste Heat' Category
NPR recently posted an in-depth article on bottom-cycling and waste heat recovery in industrial process as a growth area. Featured in the report was the massive ArcelorMittal steel mill in East Chicago, Indiana and its approach to becoming more efficient which includes the installation of boilers above the coke ovens, which generate on the order of 100MWe, or 2,400 MWh per day.
They’ve also taken advantage of pressure differential noticing that the gas that arrives to power their plant is delivered at 30 psi, the pressure at which the gas efficiently burns is 3 psi. So the company has installed turbines inline to harvest the energy in the pressure differential to generate even more power, about 16MWe or 384MWh per day.
The waste heat and gases from the process are also being harvested (bottom cycling) from the exhausted gases yielding a further 65-70MWe. In total, this complex is recovering around 250MWe from its various energy recycling programs offsetting 1,300,000 tons of CO2 emissions per year and satisfying nearly 50% of the factories energy needs.
DOE studies suggest US industries waste enough heat to harvest an estimated 200,000MWe from the processes, nearly 20% of total present US generation capacity. Clearly, this is an opportunity for improvement and recovery of existing resources and with energy prices steadily climbing, more of these programs will undoubtably be implemented.
National Public Radio Report on Energy Recycling
Recently Nevada Power Corporation, MidAmerica Holdings, and Ormat announced a project to recover waste heat at the Kern River Gas Transmission station at Goodsprings, about 35 miles south of Las Vegas. The project, scheduled to go into commercial operation subject to regulatory approval in 2010, will be sufficient to supply around 1,200 homes with electricity. This represents another important step in micro-generation and harvest and will be net positive for all parties involved.
Details of the announcement are available from Sierra Pacific Resources, the parent company of Nevada Power.
If ever you wanted to understand why the industry continues to develop coal plants, even though the negative impact is clear for all to understand, look at the chart above. You’ll notice that coal produces the most energy per unit, at a low cost per unit, and is relatively cheap from a capital cost perspective to build. With clean coal restrictions, the capital cost increases pretty radically (about 3x) but the energy output per unit and fuel cost still remain attractive.
A wind row ought to be added to this chart, but the standard unit was a little tricky to calculate. If anyone has good ideas about how to represent that aspect, please leave a comment.
Ormat and Kinder-Morgan recently signed a contract to harvest 4MW of electricity from waste heat generated at a Colorado-based natural gas compression station near Denver. It’s clear that Ormat is attempting to expand it’s footprint from pure geothermal to include waste heat for its binary power units.
Since Ormat entered the power plant operation business, there has been some speculation that the equipment business would suffer as Ormat would begin to compete with some customers. However, in what can only be termed a positive development from a shareholder perspective, Ormat’s technology is gathering momentum in the waste heat business. Yesterday the company announced an $11.5M deal with ENGAS of Spain to recover waste heat in their natural gas operations.