California utility customers could be economically punished by being in the lead in curbing greenhouse gas emissions, according to some participants in a major financial conference June 7. However, Pacific Gas & Electric believes there are long-term rewards for low-carbon behavior and that customers are likely to be shielded from financial fallout. Apparently the concern over California\u2019s economic vulnerability stems from the likelihood that 25 states powered almost exclusively by coal-fired plants in the Midwest and Southeast will have enough political clout in the U.S. Senate to make sure they gain liberal access to emissions credits under any federal cap-and-trade system. California, on the other hand, \u201cwill have to buy credits from the coal guys,\u201d said PG&E chief financial officer Chris Johns at the Citibank Investment Research Power, Gas & Utilities conference. Yet, if California utilities don\u2019t need many credits because they are low carbon emitters, then customers should be somewhat shielded from price spikes. Panelists at the conference also noted that a regulatory shield might be imposed to ease customer economic pain in any carbon trading system. PG&E\u2014which is attempting to carry the low-carbon banner among the nation\u2019s utilities\u2014supports \u201ccertain versions\u201d of a cap-and-trade system. Johns said that \u201cextreme environmentalists\u201d want a price on carbon of $100\/ton, but he thinks that is far too high and would create economic harm. \u201cBut it can\u2019t be so low that nothing happens,\u201d he added. \u201cAll of us would like to see a safety valve. So, if the price gets too high, our customers aren\u2019t damaged,\u201d Johns said.