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Energy Consumption in US Steel Industry
Here is a structure summary on US steel industry
energy consumption. Data sources are primarily from US EIA Industry Briefs.
Energy Consumption by Fuel
The steel industry used close to 2.0 quads of
energy in 1998. Nearly one-third of the industry's energy is derived from coal,
most of which is used to produce coke for use in the blast furnace. Natural gas
and electricity combined account for most of the remainder. Two major byproduct
fuels - coke oven gas and blast furnace gas - are recovered and used to generate
steam, preheat blast furnace air, or supply heat to other plant processes.
* Losses incurred during the generation and
transmission of electricity
Fuel Consumption by End Use
About 40% of the total energy input to the steel
industry is used to chemically reduce iron ore to liquid pig iron in the blast
furnace. The majority of the energy input to the blast furnace is in the form of
coke (made from coal in coke ovens), although supplemental fuels can be
injected. About 25% of the energy is used in process heating, including electric
arc furnaces and reheating furnaces. Natural gas and byproduct gases (coke oven
gas and blast furnace gas) are combusted in boilers to generate process steam.
Electricity is used to power equipment (including casting machines and rolling
mills) and to heat, light, and cool facilities.
Energy Consumption by Sector
The majority of steel industry facilities are
covered by NAICS 331111 (iron and steel mills). This sector accounts for more
than 95% of steel industry energy use. Of the remaining NAICS for the steel
industry, only 331112 (electrometallurgical feroallor products) and 3312 (sheet
product manufacturing from purchased steel) have data classified in the most
recent MECS.
| Process |
Percentage of
Total |
| Sintering |
2 |
| Cokemaking |
0 |
| Ironmaking |
39 |
| BOF Steelmaking |
3 |
| EAF Steelmaking |
13 |
| Casting |
3 |
| Boilers |
11 |
| Cogeneration |
5 |
| SUBTOTAL |
77 |
| All Other Processes (e.g., reheating,
rolling finishing)* |
23 |
| TOTAL |
100 |
* Taken as the difference between known total
industry use and known subtotal use
Energy Expenditures
Energy costs account for 17% of the cost of
manufacturing steel, on the order of $60 per ton. In 1998, the industry spent
about $6.4 billion on energy, roughly 8% of all energy expenditures in the
manufacturing sector.
* Estimated due to data being withheld to avoid
disclosing data for individual establishments.
NOTE: These estimates are open-market expenditures and exclude transfers of
energy sources from other establishments inside a company. The original
purchase, as done by the establishment from which the transfer is made, may not
be covered by the MECS.
Onsite Generation
About 10% of electricity used by the steel
industry is produced onsite, primarily through cogeneration. Almost all onsite
generation occurs in integrated steel mills. Cogeneration can provide
competitive advantages over purchased electricity, since thermal efficiencies
are much higher and excess electricity can be sold back to the grid. Several
large cogeneration facilities have been built recently, but these projects have
all been funded by third parties.
Energy Intensity
The U.S. iron and steel industry has reduced its
process energy intensity by about 45% since 1975 through energy conservation
measures, process improvements, and consolidation of the industry at product
plants that are more modern. In 1994, the average intensity (excluding
electricity losses) of producing semi-finished steel at integrated mills using
BOF steelmaking was about 20 million Btu/ton; for EAF steel producers it was 8
million Btu/ton. The charts below, which give additional measures for
steelmaking energy intensity, also illustrate the decrease of this measure over
time.
* NAICS 331111 (previous data are for SIC 3312)
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