2,129 research outputs found
Equity and Emissions Trading in China
China has embarked on an ambitious pathway for establishing a national carbon market in the next five to ten years. In this study, we analyze the distributional aspects of a Chinese emissions-trading scheme from ethical, economic, and stated-preference perspectives. We focus on the role of emissions permit allocation and first show how specific equity principles can be incorporated into the design of potential allocation schemes. We then assess the economic and distributional impacts of those allocation schemes using a computable general equilibrium model with regional detail for the Chinese economy. Finally, we conduct a survey among Chinese climate-policy experts on the basis of the simulated model impacts. The survey participants indicate a relative preference for allocation schemes that put less emissions-reduction burden on the western provinces, a medium burden on the central provinces, and a high burden on the eastern provinces. Most participants show strong support for allocating emissions permits based on consumption-based emissions responsibilities
Scaling Compliance with Coverage? Firm-level Performance in China’s Industrial Energy Conservation Program
Industrial energy conservation programs in China form a cornerstone of China’s energy and environmental management efforts, engaging thousands of major energy-using enterprises, and targeting hundreds of million tons of annual coal-equivalent energy savings during the Eleventh and Twelfth Five-Year Plans (2006 to 2015). An important question in China and other developing countries is to understand how compliance systems develop and perform, especially in settings where regulators have limited prior experience and resources to support evaluation and enforcement. We use detailed, newly-released compliance reports, combined with industrial census data on participating firms, to identify the drivers of compliance at the firm level. We find evidence consistent with manipulation of reported compliance data during the Eleventh Five-Year Plan (2006–2010), but not during the expanded program under the Twelfth Five-Year Plan (2011–2015). We show that the non-compliance rate increased with the expansion of the program, and publicly-reported reasons for non-compliance vary widely. We find that firms that are large, and new program entrants, as well as firms in cities with low growth exhibit higher non-compliance rates after program expansion. Our findings demonstrate that although expanding coverage increases potential energy savings, regulators must grapple with increased heterogeneity in firms’ internal energy-saving opportunities and capabilities as well as in the degree of external accountability to regulators. Introducing a market for energy saving or CO2 emissions may help to solve the problem of uneven abatement costs, but differences in the strength of accountability relationships could undermine performance.This research was supported by Eni S.p.A. (Award No. 5210000541), the French Development Agency (AFD, Award No. RCH‑2012‑277), ICF International (MIT Energy Initiative Associate Membership Agreement), and Shell International Limited (Award No. PT14937), founding sponsors of the MIT‑Tsinghua China Energy and Climate Project. We further acknowledge the Energy Information Administration of the U.S. Department of Energy for supporting this work through a cooperative agreement to MIT (Award No. DE‑EI0001908). At MIT, the China Energy and Climate Project is part of the Joint Program on the Science and Policy of Global Change, which is supported by a consortium of industrial sponsors and U.S. federal grants, including a grant from the U.S. Department of Energy Office of Science (Award No. DE‑FG02‑94ER61937)
Consumption-Based Adjustment of China's Emissions-Intensity Targets: An Analysis of its Potential Economic Effects
China’s Twelfth Five-Year Plan (2011–2015) aims to achieve a national carbon intensity reduction of 17% through differentiated targets at the provincial level. Allocating the national target among China’s provinces is complicated by the fact that more than half of China’s national carbon emissions are embodied in interprovincial trade, with the relatively developed eastern provinces relying on the central and western provinces for energy-intensive imports. This study develops a consistent methodology to adjust regional emissions-intensity targets for trade-related emissions transfers and assesses its economic effects on China's provinces using a regional computable general equilibrium model of the Chinese economy. This study finds that in 2007 China's eastern provinces outsource 14% of their territorial emissions to the central and western provinces. Adjusting the provincial targets for those emissions transfers increases the reduction burden for the eastern provinces by 60%, while alleviating the burden for the central and western provinces by 50% each. The CGE analysis indicates that this adjustment could double China's national welfare loss compared to the homogenous and politics-based distribution of reduction targets. A shared-responsibility approach that balances production-based and consumption-based emissions responsibilities is found to alleviate those unbalancing effects and lead to a more equal distribution of economic burden among China's provinces.The authors gratefully acknowledge the financial support for this work provided by the MIT Joint
Program on the Science and Policy of Global Change through a consortium of industrial sponsors
and Federal grants, and by the AXA Research Fund which is supporting Marco Springmann's
doctoral research. We further thank Eni S.p.A., ICF International, Shell International Limited, and
the French Development Agency (AFD), founding sponsors of the China Energy and Climate
Project. We also grateful for support provided by the Social Science Key Research Program from
National Social Science Foundation, China of Grant No. 09&ZD029 and by Rio Tinto China. We
would further like to thank John Reilly, Sergey Paltsev, Henry Jacoby and Audrey Resutek for
helpful comments, discussion and edits
Analyzing the Regional Impact of a Fossil Energy Cap in China
Decoupling fossil energy demand from economic growth is crucial to China’s sustainable development. In addition to energy and carbon intensity targets enacted under the Twelfth Five-Year Plan (2011–2015), a coal or fossil energy cap is under discussion as a way to constrain the absolute quantity of energy used. Importantly, implementation of such a cap may be compatible with existing policies and institutions. We evaluate the efficiency and distributional implications of alternative energy cap designs using a numerical general equilibrium model of China’s economy, built on the 2007 regional input-output tables for China and the Global Trade Analysis Project global data set. We find that a national cap on fossil energy implemented through a tax on final energy products and an energy saving allowance trading market is the most costeffective design, while a regional coal-only cap is the least cost-effective design. We further find that a regional coal cap results in large welfare losses in some provinces. Capping fossil energy use at the national level is found to be nearly as cost effective as a national CO2 emissions target that penalizes energy use based on carbon content.We acknowledge the support of the Ministry of Science and Technology of China through the
Institute for Energy, Environment, and Economy at Tsinghua University, and the support of the
Graduate School at Tsinghua University, which are supporting Zhang Da’s doctoral research as a
visiting scholar at the Massachusetts Institute of Technology. We further thank Eni S.p.A., ICF
International, Shell International Limited, and the French Development Agency (AFD), founding
sponsors of the China Energy and Climate Project. We also grateful for support provided by the
Social Science Key Research Program from National Social Science Foundation, China of Grant
No. 09&ZD029 and by Rio Tinto China. We would further like to thank John Reilly, Sergey
Paltsev, Kyung-min Nam, Henry Chen, Paul Kishimoto and Audrey Resutek for helpful
comments, discussion and edits
Molecular dynamics of folding of secondary structures in Go-type models of proteins
We consider six different secondary structures of proteins and construct two
types of Go-type off-lattice models: with the steric constraints and without.
The basic aminoacid-aminoacid potential is Lennard Jones for the native
contacts and a soft repulsion for the non-native contacts. The interactions are
chosen to make the target secondary structure be the native state of the
system. We provide a thorough equilibrium and kinetic characterization of the
sequences through the molecular dynamics simulations with the Langevin noise.
Models with the steric constraints are found to be better folders and to be
more stable, especially in the case of the -structures. Phononic spectra
for vibrations around the native states have low frequency gaps that correlate
with the thermodynamic stability. Folding of the secondary structures proceeds
through a well defined sequence of events. For instance, -helices fold
from the ends first. The closer to the native state, the faster establishment
of the contacts. Increasing the system size deteriorates the folding
characteristics. We study the folding times as a function of viscous friction
and find a regime of moderate friction with the linear dependence. We also
consider folding when one end of a structure is pinned which imitates
instantaneous conditions when a protein is being synthesized. We find that,
under such circumstances, folding of helices is faster and of the
-sequences slower.Comment: REVTeX, 14 pages, EPS figures included, JCP in pres
Four-wave interaction in gas and vacuum. Definition of a third order nonlinear effective susceptibility in vacuum
Semiclassical methods are used to study the nonlinear interaction of light in
vacuum in the context of four wave mixing. This study is motivated by a desire
to investigate the possibility of using recently developed powerful ultrashort
(femtosecond) laser pulses to demonstrate the existence of nonlinear effects in
vacuum, predicted by quantum electrodynamics (QED). An approach, similar to
classical nonlinear optics in a medium, is developed in this article. A third
order nonlinear effective susceptibility of vacuum is then introduced .Comment: 14 pages, 3 figure
Unfolding Rates for the Diffusion-Collision Model
In the diffusion-collision model, the unfolding rates are given by the
likelihood of secondary structural cluster dissociation. In this work, we
introduce an unfolding rate calculation for proteins whose secondary structural
elements are -helices, modeled from thermal escape over a barrier which
arises from the free energy in buried hydrophobic residues. Our results are in
good agreement with currently accepted values for the attempt rate.Comment: Shorter version of cond-mat/0011024 accepted for publication in PR
Ultraviolet and soft X--ray photon--photon elastic scattering in an electron gas
We have considered the processes which lead to elastic scattering between two
far ultraviolet or X--ray photons while they propagate inside a solid, modeled
as a simple electron gas. The new ingredient, with respect to the standard
theory of photon--photon scattering in vacuum, is the presence of low--energy,
nonrelativistic electron--hole excitations. Owing to the existence of
two--photon vertices, the scattering processes in the metal are predominantly
of second order, as opposed to fourth order for the vacuum case. The main
processes in second order are dominated by exchange of virtual plasmons between
the two photons. For two photons of similar energy , this gives
rise to a cross section rising like up to maximum of around
~cm, and then decreasing like . The maximal cross
section is found for the photon wavevector , the Fermi surface
size, which typically means a photon energy in the keV range.
Possible experiments aimed at checking the existence of these rare but
seemingly measurable elastic photon--photon scattering processes are discussed,
using in particular intense synchrotron sources.Comment: 33 pages, TeX, Version 3.1, S.I.S.S.A. preprint 35/93/C
Protein structures and optimal folding emerging from a geometrical variational principle
Novel numerical techniques, validated by an analysis of barnase and
chymotrypsin inhibitor, are used to elucidate the paramount role played by the
geometry of the protein backbone in steering the folding to the correct native
state. It is found that, irrespective of the sequence, the native state of a
protein has exceedingly large number of conformations with a given amount of
structural overlap compared to other compact artificial backbones; moreover the
conformational entropies of unrelated proteins of the same length are nearly
equal at any given stage of folding. These results are suggestive of an
extremality principle underlying protein evolution, which, in turn, is shown to
be associated with the emergence of secondary structures.Comment: Revtex, 5 pages, 5 postscript figure
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