Waitaki: assessment of reinstatement of a mothballed unit
One of the 7 units of the Waitaki power station in New Zealand was mothballed some time ago due to lack of adequate availability of powerflow. Increased flow regulation and the realization that reinstatement of the unit introduces a level of failure risk avoidance in the other aging units, prompted Meridian Energy to undertake an interdependent HydroVantage study of equipment and units.
It was found that the value of risk mitigation by itself was adequate to justify the reinstatement of the unit. Similarly it was found that increased flow regulation would also provide economic justification.
Grand Coulee: substantial reduction in risk exposure
At the Grand Coulee Generating Station in Washington State, 54 transformers at the generating units are used to step up power for transmission. To minimize the cost of an outage two spares are always held at the site.
In a study for Bonneville Power Administration, HydroVantage was used to check the validity of this strategy. After determining the condition of each of the transformers, multiple scenarios were analyzed, and it was found that the optimum strategy was to add one spare, resulting in a significant risk reduction. In addition, the cost of the current strategy of fixed transformer replacement was examined and was found to be substantial. The study provided a quantitative assessment of risk mitigation and cost savings that greatly enhanced the understanding of failure risks and facilitated the decision-making process.
Not just direct costs - ALL the future costs of failure
To accurately assess the costs of an unplanned service interruption, all costs must be taken into account, including risk-costs. HydroVantage is capable of keeping track of the four key cost streams: maintenance, capital, performance benefits and risk costs. Probabilistic analysis of these cost streams provide the broadest possible understanding of the extent of the risk and opportunities which exist at a facility.
For more information please contact:
Hans de Meel, Manager, Asset Management Services
Acres International, Niagara Falls, ON
905-374-5200
hdemeel@acres.com
