LITTLE ROCK—A witness speaking before the Arkansas Public Service Commission on Wednesday disputed Southwestern Electric Power Co.’s cost forecasts for carbon emissions at the proposed Hempstead County power plant.

David Schlissel, a senior consultant at Cambridge, Mass., based Synapse Energy Economics, also said the risks involved with possible carbon dioxide costs outweigh the price risks for natural gas.

One analysis of the future costs conducted on behalf of SWEPCO was “too narrow,” said Schlissel while being questioned by SWEPCO attorney Stephen Cuffman.