Request Monday $2-short Edition (12/12/12): It's a gas, gas, gas...

"I saw that the City of Chicago chose a supplier for residential electricity, and that they eliminated coal from the electricity mix. They didn't mention anything about renewable energy, though, so is this definitely better?"

- Brooke from Rogers Park -

The City Council of Chicago meets today to approve the supplier agreement and pave the way for residential and small business electricity supply for the entire city. After attending the Finance Committee meeting this past Monday where Aldermen reviewed the contract and asked questions of both the representatives of the city government who negotiated the contract and Integrys Energy Services, the recommended supplier. From the testimony and questions, it is clear that the contract will not include electricity generated by plants that burn coal, and it was equally unclear how the supplier planned to replace that electricity with another source. Neither the consultant representing the city nor the supplier could provide a specific answer, but through questioning, the answer seemed to come down to increased purchases from plants that burn natural gas. Although environmental groups lauded the elimination of coal, the city officials managing the contract will have much work to do to ensure that a new mix - if it indeed relies more heavily on natural gas - provides environmental benefit.

I should first be clear that eliminating coal from the electricity supply is essential, and unfortunately is a notable step. Much has been written about the ills caused by coal combustion and mining, and the EPA has fought for twenty years to enforce regulations that meant to significantly decrease pollution from coal power plants. Companies fought the implementation of those controls (meant to reduce nitrous oxides (NOx), sulfur oxides (SOx), and particulates that result from the burning of coal), and have recently begun to close down plants rather than invest in the equipment to meet these regulations that the EPA can finally fully enforce. In Chicago alone this year, we saw the closing of the Fisk and Crawford coal-fired generation plants located near the Pilsen and Little Village neighborhoods. This great step for air quality in Chicago, matched with a commitment to using the buying power of the residents of Chicago to lessen the market for coal-generated electricity, could mark a turning point for the industry.

Even with that positive step forward, there is a danger with assuming that the environmental impact will be significantly better. The lack of a commitment to replace that coal power with wind, solar, hydro, or even biomass power, leaves the door open to completely shift out coal for more natural gas. Natural gas has the reputation for cleaner burning - earned because of the significant reduction in SOx and NOx compared with coal and oil - that some apply immediately to greenhouse gas emissions. The truth is that the reduction of greenhouse gas emissions depends heavily on with which generation plants the new supplier enters into contracts on behalf of the city residents. Looking at all the electricity generating plants in the State of Illinois (thanks to the eGrid website), we can compare the possible emissions profiles of electricity mixes that do and do not include coal. For the basis of comparison, we will base the mix on the most recent ComEd environmental disclosure statement (available through the Illinois Commerce Commission website). Using the percentages from that statement, and applying the average emissions per megawatt-hour (MWh, the fundamental unit of electricity energy for large-scale generation...one MWh is 1,000 kilowatt-hours, kWh, which is the unit most rate payers are used to seeing on their bill), we can determine a total emissions per MWh for each mix. The table below summarizes the results.

You will note that the current mix uses 43% coal power, which I assume the new mix would completely replace with natural gas, bringing that total to 60%. Since each generation mix results in some amount of NOx, SOx, CO2 and CH4 (methane) emissions, those form the basis of comparison. The inclusion of methane is important to the analysis because methane is a more potent greenhouse gas than CO2 (as much as 25 times as potent). The combined impact of releasing CO2 and CH4 into the atmosphere gets communicated through the value of CO2e, carbon dioxide equivalent, which allows for an easier comparison. (The value in the table comes from using the EPA's online calculator for CO2e knowing the mix of greenhouse gases emitted.) The analysis also includes an assumption about the methane (the primary component of natural gas) that leaks throughout the mining and transportation process. Although research continues, recent research suggests that natural gas obtained through hydraulic fracturing (otherwise known as fracking) can have increased losses of methane because of the processes used by drillers and the lack of capture equipment employed. Typically, natural gas mining and transportation will result in 2-4% losses from the deposit to the plant. Research has varied, but researchers (including the National Oceanic and Atmospheric Administration) have seen as much as 9% total losses. I use 3% and 5% for natural gas obtained from traditional drilling methods and fracking extraction respectively. The representatives from Integrys noted that between 30 and 40 percent of the current natural gas supply comes from fracking, and they could not guarantee they could even account for where the gas supply comes from much less seek to eliminate it. I used 35% as an average to complete the analysis (and used the following conversion table combined with the eGrid data to determine how much gas would be needed to supply the heat energy required for electricity generation...if you are interested). With the increase in methane production during the burning of natural gas relative to coal, and the increased losses of natural gas through mining and transportation, the net reduction in CO2e as a measure of improved greenhouse gas emissions stands at about 4% for natural gas as opposed to coal. Although a decent step forward, at this juncture, we should not celebrate a 4% reduction, especially when that reduction may not improve over the two and a half years of the contract.

I will give you a couple of cautionary words of optimism. The analysis right now can only use the average of potential generators in the state because nothing is known about the actual plants from where the city will receive electricity. The city negotiators did include a requirement that the supplier provide specific documentation of each plant that will provide electricity to residents and small businesses, meaning that the selection process can produce better-than-average results.

Looking closer at the ComEd disclosure form, one will note that the current mix provides better-than-average results even including coal, so the supplier can do it. In fact, in order to make an improvement they must select significantly better-than-average generators in order to beat the current emissions level. In addition to this opportunity, the public can provide continued pressure to improve the mix further by pushing for more renewable energy, and especially for Illinois-based renewable energy.

As a last comment, although increased nuclear power would also significantly reduce CO2e emissions, there are still long-term and short-term issues with the generation of electricity through nuclear processes and the storage of waste products. Most of these plants are not located near Chicago, but transferring the risk from urban communities to rural communities located near the plants does not mean we have improved the environmental impact. When it comes down to it, the only two ways to make improvements in the quality of life of all Illinoisians, are to significantly reduce the total need for electricity in our lives, and for that which we cannot eliminate, use fully-renewable resources. Everything else will just provide a band-aid, but it will not solve the problem.