We report on an economic experiment that compares outcomes in electricity markets subject to carbon-tax and cap-and-trade policies. Under conditions of uncertainty, price-based and quantity-based policy instruments cannot be truly equivalent, so we compared three matched carbon-tax/cap-and-trade pairs with equivalent emissions targets, mean emissions, and mean carbon prices, respectively. Across these matched pairs, the cap-and-trade mechanism produced much higher wholesale electricity prices (38.5% to 52.6% higher) and lower total electricity production (2.5% to 4.0% lower) than the \equivalent" carbon tax, without any lower carbon emissions. Market participants who forecast a lower price of carbon in the cap-and-trade games ran their units more than those who forecast a higher price of carbon, which caused emissions from the dirtiest generating units (Coal and Gas Peakers) to be signicantly higher (15.2% to 33.0%) than in the carbon tax games. These merit order \mistakes" in the cap-and-trade games suggest an important advantage of the carbon tax as policy: namely, that the cost of carbon can treated by rms as a known input to production.

Any mention of climate policy was noticeably missing from President Obama's recent state of the union address. This is unfortunate because every day of inaction on climate policy by the United States government is another day that American consumers must pay substantially higher prices for products derived from crude oil, such as gasoline and diesel fuel. Moreover, a substantial fraction of the revenues from these higher prices goes to governments of countries that the US would prefer not to support.

The price of a barrel of oil has more than doubled in the past year and a half, from $60 in early 2007 to a high of $142 earlier this summer. This has led to a search for someone to blame for this price increase and for government policies to reduce oil prices.

The actions of energy traders, more pejoratively known as speculators, are being targeted by Ralph Nader, the chief executives of the major domestic airlines and many members of Congress as a major cause of this price increase. However, data from world oil market demonstrates that it is unlikely that speculators have had a noticeable impact on world oil prices.

To maximize environmental benefits from the rollout of its cap-and-trade program for greenhouse gas emissions, California should focus on achieving a positive demonstration effect from the program by doing as little as possible to harm the state's economy, as transparently as possible and as fast as possible.

Unconventional natural gas and the technologies developed to extract it in the U.S. point to a possible lower carbon energy future for China that can be facilitated through international cooperation between them, improving China's reliance on domestically produced coal, and creating economic and environmental benefits for both countries as well as the rest of the world.

With the continued successful operation of its greenhouse gas emissions market, California can become a global leader in the design and implementation of regional carbon polices. Moreover, if more regions use the California market as their starting point, then linking these programs together will be more straightforward and the ultimate goal of an effective global climate policy the more likely end result.

Last week, Stanford's Board of Trustees announced that the university would not directly invest funds from its endowment in coal mining companies.  Even the strongest advocates of this action acknowledge that it is a symbolic gesture with little direct effect on the coal industry or global greenhouse gas emissions.  But if a university administration wants to take symbolic (or real) action on climate change, is coal investment a wise choice?