The Spectacular Failure of the Kemper Coal Carbon Sequestration Plant

Kemper.Ariel

Kemper Coal & Natural Gas Facility, photo courtesy Mississippi Power Co.

The Kemper coal and natural gas facility is a 582 MW electric power plant that was supposed to cost $2.2 Billion and open in May, 2014. It hasn’t opened yet, and is now projected to cost $6.6 Billion, triple the original budget. According to Power Maghere,

The most recent filing pushes the bill to $6.66 billion. The plant was originally estimated to cost $2.2 billion in 2004, but costs began spiraling out of control almost immediately, especially once construction began in 2010 and the company discovered that many of the original designs needed major changes. Those problems appear to be continuing, as Mississippi Power said the April 1 update is “related to operational readiness and challenges in start-up and commissioning activities which includes the cost of repairs and modification to the refractory lining inside the gasifiers.”

If we break down the numbers, 582 MW of nameplate capacity power is roughly $3.78 per watt, excluding the environmental costs of mining the coal and dealing with the coal ash.

Kemper Coal w Sequestration
Nameplate Capacity 582  MW
Initial Forecast Cost $2.20  Billion
Forecast unit cost of power $3.78  $ per watt
MIT Data
Table 1

$3.78 per watt is not bad, altho it’s probably roughly the same as the retail cost of residential solar. (Which, it must be noted does not provide power at night.) However, once you factor in the cost overruns, assuming the project comes in at the current budget of $6.6 Billion, which is n 2 1/2 years late and $4.4 Billion over original budget, we are looking at $11.34 per watt; which is probably enough for 500 MW of utility scale solar, 500 MW of offshore wind, and another 500 MW of battery storage. See tables 2 and 3.

Kemper Coal w Sequestration
Nameplate Capacity 582  MW
Current Estimate of Overall Cost $6.66  Billion
Current forecast cost per unit of power $11.44  $ per watt
MIT & Power Mag Data
Table 2

Additional challenges come from the Laws of Thermodynamics and the Rube Goldberg nature of Carbon Sequestration.

The First Law states that Energy can neither be created nor destroyed, only changed from one form to another.

The Second Law states that entropy always increases, that there are always some losses, that no process can be 100% efficient, that There Is No Such Thing as a Free Lunch.

Here’s how Coal with Carbon Sequestration is supposed to work:

  1. Mine Coal.
  2. Transport it to the coal plant.
  3. Turn it into “SynGas”.
  4. Burn it.
  5. Capture 65% of the carbon dioxide, along with the toxic heavy metals in coal ash.
  6. Liquefy that CO2.
  7. Bury it underground.

This is almost as Rube Goldberg as nuclear power.

Note that energy is lost in each step.

Steps 6 and 7 are estimated to require 25% to 40% of the total energy released by the plant.

This process takes energy; probably 25% to 40% of the energy released in the burning of the coal and natural gas. Therefore, this plant with a “Nameplate capacity of 582 MW will have an effective capacity of 378.3 MW to 436.5 MW and an estimated effective cost per unit of power of $15.26 per watt to $19.07 per watt.

Kemper Coal w Sequestration
Nameplate Capacity 582  MW
Energy Cost of Sequestration 25.00  %
Estimate of Effective Capacity 436.5  MW
Estimate of Overall Cost $6.66  Billion
Estimate effective cost per unit of power $15.26  $ per watt
Estimates based on MIT Data
Table 3

.

Kemper Coal w Sequestration
Nameplate Capacity 582  MW
Energy Cost of Sequestration 40.00  %
Estimate of Effective Capacity 349.2  MW
Estimate of Overall Cost $6.66  Billion
Estimate cost per unit of power $19.07  $ per watt
Estimates based on MIT Data
Table 4

Data on the Carbon Capture and Sequestration pages of MIT, here, with additional coverage in the Clarion Ledger, here, and the NY Times, here. The official Mississippi Power  pages are here. Power Mag, here.