On March 28th, U.S. EPA released its highly controversial rulemaking which establishes a carbon dioxide (CO2) emission limit on new coal-fired power plants.  All future coal-fired power plants will have to utilize an unproven technology, carbon capture and sequestration (CCS), to meet the emission limits.  CCS involves capturing CO2 and injecting it deep beneath the earth’s surface for permanent storage.

EPA’s proposed rule would exempt from the CO2 emission limit new coal plants that begin construction in the next twelve (12) months.  Some analysts have commented that the fifteen coal-fired power plants currently slated for construction may be the last coal plants constructed in the United States.  This from Businessweek:

“This is the tail end of coal generation build-out,” said Teri Viswanath, the director of commodity markets strategy at BNP Paribas SA (BNP) in New York. “The ones we are getting today — that is going to be the last hurrah for coal-fired generation.”

Certainly that statement would appear to be true unless some of the current plants slated to utilize CCS can demonstrate its a workable technology.  However, with the risk associated with CCS and the costs of new coal power plants, cheap natural gas does seem to be the fuel of choice for new electricity generation in the United States.

Basics of the EPA Rule

EPA’s proposed Carbon Pollution Standard for New Power Plants would apply to all fossil-fuel-fired electric utility generating units (EGUs) that are larger than 25 megawatts.  These new EGUs would have to meet an output-based standard of 1,000 pounds of CO2 per megawatt-hour (lb CO2/MWh gross). 

Studies show that 95% of all newly constructed natural gas combined cycle power plant units meet the proposed standard without any add-on controls.  New coal plants without CCS currently generate around 1,800 lbs CO2/MWh gross.  Based on existing technology, the only way new coal plants could meet the 1,000 lbs standard would be through CCS.

Other key points:

  • Existing plants that begin construction in the next 12 months would be grandfathered (won’t have to meet the standard);
  • Coal plants could be built without CCS if they add it later and the average CO2 emissions over a 30 year period equal the standard.; and
  • The rule does not cover existing coal-fired power plants

Cheap Natural Gas Behind EPA’s Proposed Rule

In releasing the proposed rule, EPA provided a Regulatory Impact Analysis which projected that the rule would be very little negative effect on the cost of electricity or jobs due to low natural gas prices. The chart below shows EPA’s analysis of future natural as prices even accounting for the increased use for electric generation.


EPA states in its analysis that market forces have already shifted toward construction of natural gas electricity generating units, in part, due to recent technology used to access deposits of natural gas in the Marcellus and Utica shale formations. 

Under current and foreseeable future market conditions affecting new capacity
additions, gas-fired generating technologies can produce electricity at a lower levelized cost than coal-fired generating technologies, and therefore utilities are expected to rely heavily on combustion turbines and combined cycle plants using natural gas when they do need to expand capacity during the time horizon considered for this analysis. Current and projected natural gas prices are considerably lower than the prices observed over the past decade, largely due to advances in hydraulic fracturing and horizontal drilling techniques that have opened up new shale gas resources and substantially increased the supply of economically recoverable natural gas.

Because the large shale deposits have kept natural gas prices low, EPA finds no real impact from its proposed rule mandating CCS on new coal plants.

One has to ask the question of what happens if the dynamics on natural gas turn out differently.  What if demand increases dramatically or anticipated capacity is much lower?  Will EPA reconsider its carbon standard on new coal plants? 

The rule presents somewhat of a risky proposition by relying on an unproven technology- CCS.  So long as cheap natural gas remains, utilities will have very little incentive to really invest in CCS.