A recent article in the SJ-R stated a national figure for coal-powered generation of 30 percent. While that may be true nationally, it is not valid for the Midwest. Coal generation in the MISO (Mid-Continent Independent System Operator) area provides 50 percent to 60 percent of the energy used in this part of the country. Media reports about replacing coal generation with other sources never seem to point out the fact that coal is much more important here than a mere 30 percent.
I guess this does not fit well with the national narrative of ever decreasing coal use, but it is a very important fact that people in the Midwest need to understand. If and when we start paying for alternatives to coal generation, the amount of coal power to be replaced is a much greater share of the energy we use in this region.
The following link is a public MISO website which shows the fuel mix in MISO on 5-minute intervals.https://www.misoenergy.org/MarketsOperations/RealTimeMarketData/Pages/FuelMix.aspx
For reference the link below shows the area of the Midwest served by the MISO System.https://www.misoenergy.org/LMPContourMap/MISO_All.html
At the time I wrote this article, in mid-January, coal was providing 54 percent of the 83,659 megawatts (MW) of total generation in MISO. Wind energy, which is often mentioned as the most desirable renewable energy source, was providing a little less than 7 percent. Wind generation’s share of total MISO energy fluctuates significantly, because the wind does not blow all the time. The prior day, wind energy had been providing only 2 percent of the MISO total requirement of 90,831 megawatts. Coal was providing 55 percent.
Coal is a far larger energy provider for the Midwest than the national average indicates. This will make replacing coal locally (in the MISO) far more expensive and disruptive than the national narrative suggests. Last summer MISO peak demand reached 120,000 MW. Assuming coal was providing 55 percent of that power, 66,000 MW of coal generation would have to be replaced with something else. Some suggest that solar, wind and natural gas can fill the void. To that, I offer the following comments.
There is not a single grid-scale solar generation unit in the MISO at this time. Solar is not even included in the “Other” category of the MISO fuel mix. Having any grid scale solar power plants in operation by 2022, the effective date of the Presidents’ Clean Power Plan, is more than highly unlikely.
Wind generation is intermittent and there is no grid-scale storage for wind energy that cannot be used immediately. Because of that intermittence, 66,000 MW of wind is not equivalent to 66,000 MW of dispatchable coal or natural gas. Even if it was equivalent, at 2 MW a piece, you would need more than 33,000 new windmills in the Midwest, perhaps as many as 80,000 units. There would also have to be large investments in transmission lines to move that power.
Finally, there is natural gas. With gas the problem is not fuel supply, it is transportation. The network of gas supply lines in this part of the country was designed to move gas for space heating, not power generation. Massive and expensive improvements in the gas distribution system would be necessary for a large-scale conversion of coal generation to natural gas. We have had some experience with this problem locally. During the polar vortex winter of 2013-14, CWLP was unable to get any natural gas (at any price) for its Interstate Gas Turbine, because of congestion on the gas distribution network. All gas delivery capacity was used up for domestic heating, which had priority over any other purpose. No gas means no electric generation from gas.
Coal is much more important to reliable electricity generation in the Midwest than some would have you believe. We all need to understand that attempting to replace that coal generation would be an extremely costly effort with uncertain outcomes.
Craig Burns is the former finance director of City Water, Light and Power.
See the article here.
- On February 2, 2016