The China-in-Global Energy Model (C-GEM) is a global Computable General Equilibrium (CGE) model that captures the interaction of production, consumption and trade among multiple global regions and sectors – including five energy-intensive sectors – to analyze global energy demand, CO₂ emissions, and economic activity. The C-GEM model supplies a research platform to analyze China’s climate policy and its global implications, and is one of the major output and analysis tools developed by the China Energy and Climate Project (CECP) – a cooperative project between the Tsinghua University Institute of Energy, Environment, and Economy and the Massachusetts Institute of Technology (MIT) Joint Program on the Science and Policy of Global Change. This report serves as technical documentation to describe the C-GEM model. We provide detailed information on the model structure, underlying database, key parameters and its calibration, and important assumptions about the model. We also provide model results for the reference scenario and a sensitivity analysis for two key parameters: autonomous energy efficiency improvements (AEEI) and the elasticity of substitution between energy and value added.

This paper uses spatially-explicit analyses of climate change effects on selected key sectors of Ethiopia’s economy to estimate both sector-wise and economy-wide estimates of impacts and adaptation costs. Using four IPCC-vetted Global Circulation Models (GCMs) to bracket the uncertainty surrounding future climate outcomes, the paper finds that by 2050 climate change could cause GDP to be 8–10 percent smaller than under a no-climate change baseline; it could induce a two-fold increase in variability of growth in agriculture; and it would affect more severely the poor and certain parts of the country. The paper also finds that adaptation to climate change might cost an annual average of USD 0.8–2.8 billion; and an additional USD 1.2 to 5.8 billion if one takes into account residual damages which may not be addressed by adapting existing development plans. The paper also provides sector-specific insights on impacts and adaptation options in agriculture, road transport, and hydropower. In particular, rapid development of Ethiopia’s hydro-potential, upgrading of the road design standards, and gradual diversification of the economy away from the more climate vulnerable sectors are likely to be important elements of any climate-resilient development strategy.

© 2013 International Food Policy Research Institute

China’s recently-adopted targets for developing renewable electricity—wind, solar, and biomass—would require expansion on an unprecedented scale in China and relative to existing global installations. An important question is how far this deployment will go toward achieving China’s low carbon development goals, which include a carbon intensity reduction target of 40–45% relative to 2005 and a non-fossil primary energy target of 15% by 2020. During the period from 2010 to 2020, we find that current renewable electricity targets result in significant additional renewable energy installation and a reduction in cumulative CO2 emissions of 1.2% relative to a no policy baseline. After 2020, the role of renewables is sensitive to both economic growth and technology cost assumptions. Importantly, we find that CO2 emissions reductions due to increased renewables are offset in each year by emissions increases in non-covered sectors through 2050. By increasing reliance on renewable energy sources in the electricity sector, fossil fuel demand in the power sector falls, resulting in lower fossil fuel prices, which in turn leads to greater demand for these fuels in unconstrained sectors. We consider sensitivity to renewable electricity cost after 2020 and find that if cost falls due to policy or other reasons, renewable electricity share increases and results in slightly higher economic growth through 2050. However, regardless of the cost assumption, projected CO2 emissions reductions are very modest under a policy that only targets the supply side in the electricity sector. A policy approach that covers all sectors and allows flexibility to reduce CO2 at lowest cost—such as an emissions trading system—will prevent this emissions leakage and ensure targeted reductions in CO2 emissions are achieved over the long term.

A major uncertainty in future energy and greenhouse gas (GHG) emissions projections for China is the evolution of demand for personal transportation modes. This paper explores the implications of divergent personal transportation scenarios, either favoring private vehicles, or emphasizing a sector including all purchased transport (including local public transit, rail and aviation) as substitute for vehicle travel. Motivated by a wide range of forecasts for transport indicators in the literature, we construct plausible scenarios with low-, medium- and high-transport demand growth, and implement them in a technology-rich model which represents opportunities for fuel economy improvement and switching to plug-in hybrid-electric vehicles (PHEVs). The analysis compares primary energy use and GHG emissions in China in the absence and presence of climate policies. We find that a policy that extends the current Chinese emissions-intensity goals through 2050 mostly affects other sectors with lower abatement costs, and so only lightly engages household transport, permitting nearly the same large increases in refined oil demand (by more than five times) and private vehicle stocks (to 430–500 million) as in the reference case. A stringent climate stabilization policy affects household transport, limiting vehicle ownership and petroleum demand, but drives up the share of household spending on transport, and carries high economy-wide costs. The large projected scale of vehicle fleets, refined oil use and transport purchases all suggest that the rate and type of travel demand growth deserves attention by policymakers, as China seeks to address its energy, environmental, and economic goals.