Alberta power utility Enmax Corp. said yesterday it is building a huge new power station in Southern Alberta fired with natural gas, partly to help boost the provincial grid’s reliability after Alberta’s aggressive expansion into wind energy made it vulnerable to power disruption.“We now have so much windpower generation that we need to fall back on reliable sources of power,” said Peter Hunt, an Enmax spokesman.
“The problem with wind power is that the wind doesn’t blow all the time, so the greater percentage of the system depends on wind, the more vulnerable to disruption the system becomes when the wind stops blowing.”
The 1,200-megawatt station, which industry sources say would cost about $2-billion, would produce enough power to supply two-thirds of Calgary’s needs.
Alberta expanded into windpower generation aggressively since deregulating its electricity industry eight years ago. With more than 4% of its power coming from wind farms in the southern part of the province, it is the national leader in the green-energy source.
But the growth turned out to be too much of a good thing and the provincial grid operator, Alberta Electric System Operator, slapped a ban last April on the construction of any more wind farms until the reliability issues are resolved.
While environmentally friendly, the typical wind farm in Southern Alberta can harvest wind only 35% of the time.
Electricity has to be used instantaneously, cannot be reliably stored and has to be kept within a narrow band of voltage and frequency.
Warren Frost, vice-president of operations and reliability with AESO, said the new station should solve some of the grid’s variability challenges.
“It’s good news for Alberta in terms of getting another source of generation,” he said. “Alberta is continuing to grow at a phenomenal rate and another major investment in the generation of supply is a good thing.”
While Enmax has not picked a site for the station, Mr. Hunt said it will be located close to wind power generation areas so it can quickly pick up the load when the wind starts to die down. The first phase is expected to be completed in the next three years.
An advantage of natural gasfired stations is that they can be turned on quickly, just like cooking gas. Coal-fired stations, on the other hand, need a long time to ramp up.
Enmax, itself a major producer of power from wind, said it hopes the new power station will firm up the transmission grid so more wind farms can be developed in the future.
Alberta is expected to require additional capacity of up to 3,800 megawatts in the next decade.
By Claudia Cattaneo, Financial Post
20 April 2007