Greenhouse Gas Emissions from High Demand, Natural Gas-Intensive Energy Scenarios

Since coal and oil emit 70% and 30% more CO2 per unit of energy than natural gas (methane), fuel switching to natural gas is an obvious pathway to lower CO2 emissions and reduced theorized greenhouse warming. However, methane is, itself, a strong greenhouse gas so the CO2 advantages of natural gas may be offset by leaks in the natural gas recovery and supply system. Simple models of atmospheric CO2 and methane are used to test this hypothesis for several natural gas-intensive energy scenarios, including the work of Ausubel et al. (1988). It is found that the methane leaks are significant and may increase the total "greenhouse effect" from natural gas-intensive energy scenarios by 10%. Furthermore, because methane is short-lived in the atmosphere, leaking methane from natural gas-intensive, high energy growth scenarios effectively recharges the concentration of atmospheric methane continuously. For such scenarios, the problem of methane leaks is even more serious. A second objective is to explore some high demand scenarios that describe the role of methane leaks in the greenhouse tradeoff between gas and coal as energy sources. It is found that the uncertainty in the methane leaks from the natural gas system are large enough to consume the CO2 advantages from using natural gas instead of coal for 20% of the market share

Liquid Hydrogen Aircraft and the Greenhouse Effect

A simple model of the world air market is used to test the role that liquid hydrogen (LH2) aircraft might play in reducing carbon dioxide (CO2) emissions from this sector of the economy. I assume that LH2 aircraft can penetrate up to 70% of the market and will do so along a logistic diffusion curve over 40 years. Using two scenarios -- high and low demand -- I find that although LH2 aircraft and the LH2 supply system can be configured to release no CO2, the remaining conventional aircraft in the market continue to play a large role in the total sector CO2 emissions. The model is very sensitive to the balance between the LH2 substitution effect, market growth, and efficiency growth. Liquid hydrogen aircraft can help reduce CO2 emissions, but reducing CO2 emissions below current levels will also require constraints on growth in the entire air market

Leaking Methane from Natural Gas Vehicles: Implications for Transportation Policy in the Greenhouse Era

A model of the U.S. automobile market is used to test the role that natural gas vehicles (NGVs) might play in reducing greenhouse-gas emissions. Since natural gas (primarily methane) emits less CO2 per unit of energy than petroleum products, NGVs are an obvious pathway to lower CO2 emissions. High- and low-demand scenarios are used to forecast the emissions from unrestricted growth and a modest form of conservation, respectively. Based on these scenarios, a reference scenario is developed that projects a possible future path of automobile use and efficiency. It is found that without a dramatic increase in automobile use, fuel consumption and greenhouse-gas emissions from automobiles in the United States will probably decrease in the future, provided that efficiency continues to improve at modest rates. In theory, NGVs can help shift emissions even further down. A second objective is to quantify the role that leaking methane might play in offsetting some of the greenhouse advantages of NGVs. To do this, a simple atmospheric chemistry model is applied to the reference scenario; several leak rates and feedback factors are used to test the sensitivity of the projected greenhouse forcing from now until 2050. Committed warming beyond 2050 is not included, and the results should be interpreted with that in mind. It is highly unlikely that switching automobiles from gasoline to natural gas will appreciably lower future greenhouse forcing. Constraints on vehicle miles travelled as well as continued improvements in vehicle efficiency will make a much larger contribution towards controlling global warming

The Kyoto Protocol Carbon Bubble: Implications for Russia, Ukraine, and Emission Trading

The emission targets adopted in the Kyoto Protocol far exceeded the likely level of emissions from Russia and Ukraine. These countries could sell their "bubbles" if the Protocol enters into force and industrialized countries establish an international emission trading system. Using the most recent, comprehensive scenarios for emissions of carbon dioxide from the energy system we estimate that during the Protocol's 2008-2012 "budget period" the bubble will range from 9MtC (million tons of carbon) to 900 MtC for Russia and 3 MtC to 200 MtC for Ukraine. Even scenarios with high economic growth and carbon-intensive technologies do not burst the bubble before the budget period. In the central ("middle course") scenario the total carbon bubble exceeds 100 MtC, is worth 22 to 170 billion US Dollars (4 to 34 billion US Dollars per year), and does not burst until 2040. This flow of assets, which could exceed Russian earnings from natural gas exports ($10 billion in 1997), is comparable with projected total investments in the Russian energy system for 2008-2012. If directed towards low-carbon infrastructure investments (e.g., gas pipelines, safe nuclear power), bubble transfers could reinforce and partially lock-in decarbonization of the world energy system

A Model for Estimating Future Emissions of Sulfur Hexafluoride and Perfluorocarbons

Sulfur hexafluoride (SF6), perfluoromethane (CF4) and perfluoroethane (C2F6) are strong greenhouse gases with long atmospheric residence times. Under the Kyoto Protocol to the Framework Convention on Climate Change adopted in December 1997, industrialized nations agreed to regulate their emissions of these gases. Here we present a simple spreadsheet model that is useful for projecting future emissions and analyzing compliance with regulatory commitments. We use atmospheric measurements of these gases and engineering studies to derive emission factors and scenarios for each of the major anthropogenic sources (leakage from electrical equipment, magnesium casting, aluminum smelting and semiconductor fabrication). Our model is useful for policy analysis because it divides the world into regions of nations that correspond with the political coalitions that dominate the international negotiations through which regulatory commitments are adopted. We show that although firms in many industrialized countries are already limiting emissions, without further policy intervention global emissions will rise 150% (CF4 and C2F6) and 210% (SF6) between 1990 to 2050; radiative forcing will increase 0.026 W m-2. Full application of available low- and negative-cost policies in industrialized nations would cut that radiative forcing by one-quarter. We also quantify plausible future manipulations to governmental data and show their possible effect on compliance with the targets of the Kyoto Protocol. West European nations can "cut" their emissions of these gases by half by 2010 simply by manipulating emission factors within the current bounds of uncertainty. The need for more complete and transparent data on these gases is urgent

An Empirical Study of Review Mechanisms in Environmental Regimes

This report is part of a large scale comparison of how implementation review mechanisms (IRMs) are used in international environmental agreements. Broadly, IRMs are the means by which data is exchanged and gathered, reviewed and assessed in the context of an international agreement, and by which problems of compliance and inadequate performance are managed. Here we describe the data protocol that is being used in assembling a database of review mechanisms and explain the rationale behind all the major questions in the protocol. The protocol consists of questions about the general features of agreements as well as more focussed questions concerning: how information relating to national performance and compliance is gathered and disseminated; how that information is assessed; and the means by which the parties and the agreement respond to potential problems of noncompliance and inadequate performance. The database is useful in part because it organizes information about different international environmental agreements into a comparable format and thus aids in the selection of appropriate cases and comparisons for further research. It is also useful because it can aid in the testing of hypotheses about which aspects of international agreements and review mechanisms lead agreements to be more effective. We are now using it for both purposes, in addition to extending the number of cases in the database. To date, over fifty cases have been coded using the protocol. Here we also report some observations and hypotheses derived from working with the data from those cases. These include: 1) a hypothesis that review mechanisms tend to grow as needed to fulfill demand for specific functions; 2) a hypothesis that review mechanisms might help the parties to an agreement address various forms of complexity that arise in negotiating and managing international agreements; 3) a questions as to whether and how often institutions that are formally outside a particular agreement but with competence or power in the issue-area de facto provide the review mechanisms for the agreement; 4) a question as to whether review mechanisms make their largest contribution to effectiveness when the obligations of an agreement are precise or vague; 5) a question as to whether in practice some of the functions of review mechanisms are performed by dispute resolution mechanisms, which tend to be formally created in most international agreements (but appear to be rarely used in environmental agreements)

The Early Operation of the Montreal Protocol's Non-Compliance Procedure

In this essay, the author assesses the operation of the Non-Compliance Procedure of the Montreal Protocol on Substances That Deplete the Ozone Layer. Although in operation for only six years, the Procedure and its standing Implementation Committee have already made significant contributions to the effectiveness of the Montreal Protocol. The Implementation Committee serves as a forum for discussing compliance-related issues; it has played a central role in managing individual cases of compliance. The author applies some lessons from the Montreal Protocol experience to the design of noncompliance procedures and similar mechanisms in other multilateral environmental agreements. He focuses on the Multilateral Consultative Process (Article 13) of the United Nations Framework Convention on Climate Change

Leaking Methane from Natural Gas Vehicles: Implications for US Greenhouse Gas Reductions from the Automobile Sector

A model of the US automobile market is used to test the role that natural gas vehicles (NGVs) might play in reducing greenhouse gas emissions. Since natural gas (methane) emits less CO2 per unit of energy than petroleum products, NGVs are an obvious pathway to lower CO2 emissions. High and low demand scenarios are used to forecast the emissions from unrestricted growth and a modest program of conservation, respectively. Based on these scenarios, a reference scenario is developed that projects a possible future path of automobile use and efficiency. I find that without dramatic shifts in automobile use, fuel consumption and greenhouse gas emissions will probably decrease in the future, provided that efficiency continues to improve at modest rates. In theory, NGVs can help shift emissions even further down. A second objective is to quantify the role that leaking natural gas (methane) might play in offsetting some of the greenhouse advantages of NGVs. A simple atmospheric chemistry model is applied to the reference case. Based on current estimated leakage rates of about 3.6%, nearly all the greenhouse advantages of NGVs are consumed by the greenhouse contribution from leaking methane. If oil operations (used to supply gasoline to conventional vehicles) also yield natural gas leaks then the relative case for NGVs should be more favorable. Scenarios that account for this are also explored. However, it appears that even if this source of methane is included, NGVs do not have substantial advantage over oil-based automobile fuels for two reasons: 1) the CO2 advantage of natural gas (compared with oil) is compensated by the methane leakage, and 2) there are not large gains in efficiency from using natural gas instead of oil products in automobiles

The Kyoto Protocol Emission Allocations: Windfall Surpluses for Russia and Ukraine

The Emission targets adopted in the Kyoto Protocol far exceeded the likely level of emissions from Russia and Ukraine. These countries could sell their surpluses if the Protocol is followed and industrialized countries establish an international emission trading system. Critics have condemned the potential sale and dubbed the surplus 'hot air' because it does not represent any reduction in emissions below the level that would have occurred anyway. Using the most recent, comprehensive regional scenarios for the emissions of carbon dioxide from the energy system, we estimate that during the Protocol's 2008-2012 'budget period' the surplus will range from 9 MtC (million tons of Carbon) to 900 MtC for Russia and from 3 MtC to 200 MtC for Ukraine. Even scenarios with high economic growth and carbon-intensive technologies do not exhaust the surplus before the budget period. In the central ('middle course') scenario, the total carbon surplus exceeds 100 MtC and is worth 22 to 170 billion U.S. dollars (4 to 34 billion U.S. dollars per year). This flow of revenues, which could exceed Russian earnings from natural gas exports ($10 billion in 1997), is comparable with the projected total investments of the Russian energy system for 2008-2012. If directed towards low-carbon infrastructure investments (e.g. gas pipelines), surplus transfers could reinforce and partially lock-in decarbonization of the world energy system

The Past and Future of Global Mobility

How much will people travel in the future? Which modes of transport will they use? Where will traffic be most intense? The answers are critical for planning infrastructures and for assessing the consequences of mobility. They will help societies anticipate environmental problems such as regional acid rain and global warming. With growing wealth, people everywhere travel farther and faster. That trend inevitably brings a shift in the dominant transportation technologies. In an attempt to answer these questions, the authors have composed a scenario for the future volume of passenger travel, as well as the relative prevalence of different forms of transportation through the year 2050