AUSTIN — The operator of Texas’ electric grid has issued a call to the public for energy conservation Monday as excessive heat could lead to an energy emergency.At 9 p.m., the Electric Reliability Council of Texas issued a watch indicating that it has projected a shortage in energy reserves Monday “with no market solution available,” according to an active operations message posted to the ERCOT website. ERCOT is also calling for voluntary energy conservation.ERCOT stopped short of indicating power might be cut off and said that “no system-wide outages are expected,” according to a news release.The watch is a notification preceding an “energy emergency alert,” which is a more severe alert indicating ERCOT might order operations to shut down or be limited at large scale electric users such as manufacturing facilities or big box stores. Those alerts range from calls for conservation to rolling blackouts.A 9:30 p.m. projection indicated Texas could smash its all-time electricity demand Monday with 80 gigawatts of use projected in the afternoon. That is above what ERCOT predicted the summer demand peak would hit in a seasonal preparedness report.The tightest hour will be between 2 p.m. and 3 p.m. during which ERCOT is predicting that wind energy will only be producing at roughly 8% of its capacity. At that time, solar power will be producing at 81% capacity, but makes up a much smaller share of Texas’ total energy generation.Dispatchable energy, which consist of mainly natural gas power plants, will be relied on to generate the bulk of electricity during those peak demand hours.The alert comes as temperatures in Dallas are expected to reach and possibly top 105 degrees Monday. The National Weather Service has issued an excessive heat warning for the entire Dallas-Fort Worth area that sweeps across a vast swath of the state. Isolated high temperatures could reach as high as 112 degrees, the weather service said.The heat wave is driving increased electric use and could lead to tight energy conditions all week.