Energy is used in PotashCorp's mining and milling processes, in its chemical manufacturing operations and in transportation.
Direct Energy Used
The company's operations are energy-intensive, particularly in nitrogen where 35.2 MMBtus of natural gas are required to produce one short ton of ammonia.
Total direct energy use was 161,600 terajoules (TJ) in 2007, which included energy from coal, fuel oil, natural gas and purchased electricity, with the nitrogen operations accounting for 87 percent.
PotashCorp's Direct Energy Use |
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| (000 TJ) | 2003 | 2004 | 2005 | 2006 | 2007 |
| Total Energy Used | 162.9 | 153.8 | 151.9 | 148.2 | 161.6 |
| Source: PotashCorp | |||||
Energy use dipped in 2004 after the permanent shutdown of the company's Memphis facility and indefinite shutdown of the ammonia plant at Geismar. In 2007, energy use climbed back to the 2003 level with the increase in production at the other nitrogen facilities.
PotashCorp's Energy Use By Division |
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| (% of Total) | 2003 | 2004 | 2005 | 2006 | 2007 |
| Potash | 5.4 | 7.6 | 8.2 | 7.4 | 7.8 |
| Nitrogen | 87.7 | 85.9 | 85.6 | 86.7 | 87.1 |
| Phosphate | 6.9 | 6.5 | 6.2 | 5.9 | 5.1 |
| Total Energy Use | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 |
| Source: PotashCorp | |||||
Indirect Energy Use
PotashCorp indirect energy use by its electricity providers was approximately 36.0 thousand TJs.
Energy Efficiency
Between 2003 and 2007, energy efficiency improved by 5.9 percent at potash facilities, 3.1 percent at nitrogen facilities and 23.4 percent at phosphate facilities. The efficiency is based on the total energy used at each of the divisions, and the tonnes of potash, ammonia and phosphoric acid production for the potash, nitrogen and phosphate divisions, respectively.
Energy Efficiency by Division |
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| (TJ/000s Tonnes of Product) | 2003 | 2004 | 2005 | 2006 | 2007 |
| Potash | 1.7 | 1.6 | 1.5 | 1.8 | 1.6 |
| Nitrogen | 42.4 | 42.3 | 42.3 | 41.9 | 41.1 |
| Phosphate | 4.7 | 5.1 | 4.5 | 4.1 | 3.6 |
| Source: PotashCorp | |||||
Some of the company's energy efficiency initiatives in 2007 included:
- Augusta revamped two of the compressors in the ammonia plant, which increased the efficiency of the plant by approximately 1.4 percent or more than 300,000 MMBtus per year at normal production rates.
- Geismar increased the efficiency of one of its nitric acid plants by more than 28,000 MMBtus per year at normal production rates.
- Aurora follows a program of continuing improvement. As motors are replaced, high efficiency motors are purchased and installed. As new electrical transformers and motors are purchased, they are being sized within 90 percent of full load rating, resulting in a more efficient installation.
- Cincinnati replaced an older boiler with one built to a much more efficient design.
Sources of Energy
The major sources of energy used by PotashCorp in 2007 were natural gas as a feedstock for process use (53 percent), carbon fuels (40 percent) and purchased electricity (7 percent).
Energy from Cogeneration and Waste Heat Recovery
PotashCorp has taken steps to optimize the generation of electricity or power by capturing the waste heat from its operations. It has also taken advantage of cogeneration opportunities.
Examples of Cogeneration and Waste Heat Recovery |
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| White Springs | This Florida phosphate operation has 46 MW of cogeneration capacity. It uses the waste heat from operations to generate enough electricity to supply nearly all its chemical manufacturing operations. The facility has recently been modified to capture more waste heat and generate an additional 2.5 MW of electricity per day. |
| Aurora | This North Carolina facility has 42 MW of cogeneration capacity. |
| Augusta | Heat from gas turbine exhaust is recovered at this Georgia plant for both process and steam use internally. The mechanical power developed is equivalent to 19 MW. |
| Trinidad | A generator produces all the electricity needs (11 MW) for the newest ammonia plant at this facility. |
| Cory | This Saskatchewan potash plant takes steam from a nearby cogeneration plant (SaskEnergy/Atco joint venture) that produces electricity and steam. The purchased steam replaces a less efficient direct-fired boiler. |
| Patience Lake | This potash plant in Saskatchewan is working on heat recovery from the recovery brine, which will reduce the input requirement of the direct-fired brine heaters. |
| Lima | This Ohio nitrogen plant uses a gas turbine driver to recover the equivalent of 8.8 MW of electrical power. Waste heat energy from exhaust gases is recovered in the ammonia reforming process. |
Energy Costs
PotashCorp's energy costs have increased significantly over the past five years, reflecting the higher prices paid for natural gas, carbon fuels and electricity as well as increased production.
Energy Costs |
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| ($ million) | 2003 | 2004 | 2005 | 2006 | 2007 |
| Total Energy Costs | 627.1 | 697.9 | 822.7 | 751.9 | 845.2 |
| Source: PotashCorp | |||||