The MIT interdisciplinary study on The Future of Coal is by far the best objective source on CO2 mitigation related to coal-fired electrical generation. There is a lot of research summarized in the core 192-page report [PDF]. Sections of the report are available on the MIT website. If you want to take away just one key concept, it is that besides introducing a price signal on carbon emissions, we need to get serious about nuclear power generation, and to demonstrate successful large-scale CCS. Remember that China alone is building one to two new dirty coal plants per week. Utilities making investment decisions today are faced with unacceptable uncertainty about the cost of carbon emissions and the capital and operating costs of CCS [and even whether CCS is feasible].
From the full report:
Today, and independent of whatever carbon constraints may be chosen, the priority objective with respect to coal should be the successful large-scale demonstration of the technical, economic, and environmental performance of the technologies that make up all of the major components of a large-scale integrated CCS system — capture, transportation and storage. Such demonstrations are a prerequisite for broad deployment at gigatonne scale in response to the adoption of a future carbon mitigation policy, as well as for easing the trade-off between restraining emissions from fossil resource use and meeting the world’s future energy needs.
As to the carbon price signal, the economic models used in the study suggest that about $30 per ton of CO2 is necessary to incentivize the global switch to CCS. As the graphic at left shows, the MIT projections indicate that by 2050 the “business as usual case” CO2 emissions from coal generation will be about 32 GigaTons per year. With both expanded nuclear power and CCS the annual coal emissions should drop by 90% to around 3 Gt/annum. However, note that about 80% of that reduction is due to expanded nuclear power. So,
- the most important policy options are those that facilitate safe, economical nuclear power;
- policy that makes CCS economical has the potential to cut the coal-power emissions by about 50% .
From the Executive Summary:
This MIT study examines the role of coal as an energy source in a world where constraints on carbon emissions are adopted to mitigate global warming. Our first premise is that the risks of global warming are real and that the United States and other governments should and will take action to restrict the emission of CO2 and other greenhouse gases. Our second and equally important premise is that coal will continue to play a large and indispensable role in a greenhouse gas constrained world. Indeed, the challenge for governments and industry is to find a path that mitigates carbon emissions yet continues to utilize coal to meet urgent energy needs, especially in developing economies. Th e scale of the enterprise is vast. (See Box 1).
Our purpose is to identify the measures that should be taken to assure the availability of demonstrated technologies that would facilitate the achievement of carbon emission reduction goals, while continuing to rely on coal to meet a significant fraction of the world’s energy needs. Our study has not analyzed alternative carbon emission control policies and accordingly the study does not make recommendations on what carbon mitigation measure should be adopted today. Nevertheless, our hope is that the study will contribute to prompt adoption of a comprehensive U.S. policy on carbon emissions.
We believe that coal use will increase under any foreseeable scenario because it is cheap and abundant. Coal can provide usable energy at a cost of between $1 and $2 per MMBtu compared to $6 to $12 per MMBtu for oil and natural gas. Moreover, coal resources are distributed in regions of the world other than the Persian Gulf, the unstable region that contains the largest reserves of oil and gas. In particular the United States, China and India have immense coal reserves. For them, as well as for importers of coal in Europe and East Asia, economics and security of supply are significant incentives for the continuing use of coal. Carbon-free technologies, chiefl y nuclear and renewable energy for electricity, will also play an important role in a carbon-constrained world, but absent a technological breakthrough that we do not foresee, coal, in significant quantities, will remain indispensable.
However, coal also can have significant adverse environmental impacts in its production and use. Over the past two decades major progress has been made in reducing the emissions of so-called “criteria” air pollutants: sulfur oxides, nitrogen oxides, and particulates from coal combustion plants, and regulations have recently been put into place to reduce mercury emissions. Our focus in this study is on approaches for controlling CO2 emissions. These emissions are relatively large per Btu of heat energy produced by coal because of its high carbon content.
We conclude that CO2 capture and sequestration (CCS) is the critical enabling technology that would reduce CO2 emissions significantly while also allowing coal to meet the world’s pressing energy needs.
To explore this prospect, our study employs the Emissions Predictions and Policy Analysis (EPPA) model, developed at MIT, to prepare scenarios of global coal use and CO2 emissions under various assumptions about the level and timing of the carbon charge1 that might be imposed on CO2 emissions and the cost of removing CO2 from coal. The response of the global economy to placing a price on CO2 emissions is manifold: less energy is used, there is switching to lower carbon fuels, the efficiency of new and existing power plants is improved, and new carbon control technologies are introduced, for example CCS. In characterizing the CO2 emission price, we employ a “high” price trajectory that starts at $25/tonne-CO2 in 2015 and increases thereafter at a real rate of 4% per year. The $25 per tonne price is signifi cant because it approaches the level that makes CCS technology economic.
We also examine a “low” price trajectory that begins with a CO2 emission price of $7/tonne in 2010 and increases at a rate of 5% thereaft er. The key characteristic of the “low” price is that it reaches the initial “high” price level nearly 25 years later. Other assumptions studied include the development of nuclear power to 2050 (limited or expanded) and the profi le of natural gas prices (as calculated by the model or at a lower level).
Our conclusion is that coal will continue to be used to meet the world’s energy needs in significant quantities. The high CO2-price scenario leads to a substantial reduction in coal use in 2050 relative to “business as usual” (BAU), but still with increased coal use relative to 2000 in most cases. In such a carbon-constrained world, CCS is the critical future technology option for reducing CO2 emissions while keeping coal use above today’s level. Table 1 shows the case with higher CO2 prices and applying the EPPA model’s reference projection for natural gas prices. The availability of CCS makes a signifi cant difference in the utilization of coal at mid-century regardless of the level of the CO2 prices (not shown in the table) or the assumption about nuclear power growth. With CCS more coal is used in 2050 than today, while global CO2 emissions from all sources of energy are only slightly higher than today’s level and less than half of the BAU level. A major contributor to the global emissions reduction for 2050 is the reduction in CO2 emissions from coal to half or less of today’s level and to one-sixth or less that in the BAU projection.
As discussed in our earlier post, the FutureGen project is on the rocks. The MIT study may have anticipated this:
The flagship DOE project, FutureGen, is consistent with our priority recommendation to initiate integrated demonstration projects at scale. However, we have some concerns about this particular project, specifi cally the need to clarify better the project objectives (research vs. demonstration), the inclusion of international partners that may further muddle the objectives, and whether political realities will allow the FutureGen consortium the freedom to operate this project in a manner that will inform private sector investment decisions.
Where U.S. federal support for CSS goes from here is unknown [to me].
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