By PRISCILLA WAGGONER

Courier reporter

ALAMOSA — When electricity suddenly went out in parts of Alamosa, Rio Grande and Saguache counties at 6:00 p.m. on Thursday night, local residents got some first-hand experience with the complexities of energy infrastructure in Colorado. The outage, instituted by Xcel in response to the fires burning in Boulder County about 260 miles away, lasted about four hours as temperatures plummeted into the single digits. There were also controlled outages instituted in Summit, Grand, Lake and Eagle counties.

Although the problem originated in the flow of natural gas from the area where the intense fire was burning – the same part of the system that provides natural gas to the valley - the fix to what could have developed into major problems with the valley receiving the natural gas involved cutting off the electricity.

As explained by Michelle Aguayo, media relations representative with Xcel Energy in Denver, “We had to shut down the impacted natural gas infrastructure due to fire flashing through [Boulder County] and that shut down resulted in a loss of pressure on the mountain natural gas system. This part of the system helps provide pressure and gas supply to the natural gas system leading into the mountain communities. Not having these critical facilities available put customers and communities at risk of losing natural gas service, especially as more customers used their furnaces to heat their homes as the temperatures dropped after the sun set.”

Many furnaces are attached to thermostats that cause the natural gas to kick in when temperatures inside the building reach a specific point. As the heaters kick on, they draw on the natural gas system, drawing on the gas supply that’s available and impacting pressure, which, as Aguayo explains, was already low due to the natural gas being shut off in the areas where the fire was burning.

Furnaces are also equipped with electric fans. Without the fan operating the furnace, the furnace does not begin to heat. By shutting off the power that would cause the electric fan to work and the furnace to heat, Xcel was able to control the draw on the natural gas system and prevent the potential of a larger natural gas outage in the mountain system.

Had they not taken that step, according to Aguayo, there would have been a large natural gas outage throughout the seven counties that were impacted. Restoring gas in such a sizeable area would have required a large number of Xcel service employees to turn off and then relight furnaces in individual homes and businesses. The amount of time required to turn off and relight that many furnaces could have taken days to weeks to restore for the entire mountain system, says Aguayo.

When Xcel initially contacted the media to get out the word that there would be power outages in the seven mountain communities, the company had predicted the outage would last throughout the night.

“Fortunately, our crews were able to reach the impacted equipment and restore its capabilities to serve our customers, resulting in shorter than planned controlled electric outages,” Aguayo told The Courier.

Not all of Alamosa was impacted as parts of downtown and the northern part of the city experienced no power interruption. The answer to why that was the case was not received prior to going to press and will be explained when that information becomes available from Xcel.