GRAPEVINE, Texas — Renewable energy company Greenhunter Energy declined to comment Tuesday on what the New York Stock Exchange called "unusual activity" after its stock jumped 61.7 percent in a single day.
Greenhunter shares rose 71 cents to close at $1.86. After hours, the stock advanced another 15 cents.
Contacted by the NYSE, Greenhunter said its company policy was not to comment on unusual market activity. A company spokesman said the same when contacted by The Associated Press.
Greenhunter works on wind, hydropower, geothermal solar and other renewable energy projects. It has the nation's largest biodiesel refinery in Houston and a biomass-fired power plant in Brawley, Calif.